The document discusses various topics related to bread science and technology. It covers different types of bread like white bread, wholemeal bread, multigrain bread, and flatbreads. It describes the basic steps in the bread making process and discusses key ingredients like wheat flour, yeast, and minor additives. The document also covers the nutritional composition and qualities of different breads.

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Baking Science and Technology I
3(2-1)
By
Prof. Dr. Faqir Muhammad Anjum

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Theory
 Bread types and Formulations.
 Wheat flour: Components and functions. Shortenings: Types,
functions, sources and mechanisms.
 Sweeteners: Types, functions.
 Yeast: Types, functions, factors influencing fermentation.
 Minor ingredients: yeast nutrients, enzymatic supplements,
oxidizing agents, salt, mold inhibitors and dough improvers.
 Bread making processes: Straight dough, sponge dough, rapid
processing, mechanical dough development.
 Mixing and dough processing: Functions of mixing, mixer types,
fermentation, dough transfer systems, dough make up; dividing,
rounding and moulding, panning and proofing.
 Baking process: Stages, baking reactions, thermal reactions, bread
cooling, shelf life properties of bread and related products. Bread
packaging and storage. Bread spoilage and staling, factors and
control measures.
 Flat bread technology: Frozen dough products and pizza.
Course Contents

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Practical
 Bread baking, types of breads, effects of water absorption and
dough mixing time. Variations in fermentation and proofing time.
Effects of shortenings, emulsifier, oxidants, flour protein
variation, amylases and sweeteners on bread. Comparison of
various dough making procedures. Field trip.
Text Books
 1. Cauvain, S.P. 2003. Bread Making - Improving Quality.
Woodhead Pub. Ltd., Cambridge, UK.
 2. Matz, S.A. 1996. Bakery Technology and Engineering. CBS Pub.
& Dis., New Delhi, India.
Recommended Books
 1. Cauvain, S.P. and S.Y. Linda. 1998. Technology of Bread
Making. Blackie
 Academic & Professional, London, UK
 2. Quail, K.J. 1996. Arabic Bread Production. American
Association of Cereal Chemists, Inc., St. Paul, Minnesota, USA.

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 Bread
 Staple food made from flour mixed with other
dry and liquid ingredients, usually combined with
a leavening agent, and kneaded, shaped into
loaves, and baked
 In Western cultures, bread was important food
made from grain staple
 Originated during modern stone age, ~8000 BCE.
May be world’s oldest food.

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 Making of bread did not happen immediately.
 Whole grain was eaten hard and raw, softened,
later cracked.
 Bulgur – Middle East
 Groats – Europe
 Origin of unleavened bread before 8000 BCE.
 Unleavened bread consumed for thousands of
years before leavened bread was made.
 Egyptians, around 3000 B.C., believed to be first
to baked leavened bread.

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 Differ in sizes, shapes textures, and taste all over
the world
 Vary in size from small sticks to loaves weighing
several kilograms
 The product terminology is strongly linked with
local consumer preferences and traditions
 All of the bread types require their own
processing techniques, processing equipment and
process control mechanisms

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 Nutritional Quality
 Provide significant source of protein complex
carbohydrates (mainly starch), fiber, vitamins
and minerals
 The nutritional contributions are greatest in
whole-wheat breads since they require
conversion of 100% of the grain into flour
 Removal of bran and germ components from
the wheat grain changes the overall nutritional
qualities of the resultant product

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 Sometimes the formula is enriched with
additional nutrients
 The enrichment mainly comprises the addition of
calcium, some of the essential amino acids, and an
assimilable form of iron
 Bread was selected as a means of nutritional
improvements for Americans during late 1930s
and early 1940s.

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 Only in leavened bread.
 B vitamins and iron added to bread.
 Program eliminated beriberi and pellagra in
United States
 Automation of bread making
 Bread slicer invented in 1912
 Otto Frederick Rohwedder is considered to be
the father of sliced bread.

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 Nutritional Composition of Bread
(per 100g)
Components White
Bread
Brown
Bread
Wholemeal
Bread
Carbohydrate 49.3 44.3 41.6
Protein 8.4 8.5 9.2
Dietary Fiber 2.7 4.7 7.1
Fat 1.9 2.0 2.5
(Cauvain and Young, 1998)

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 Basic Steps of Breadmaking
An Overview
 There are a few basic steps that form the basis
of all breadmaking. They can be listed as
follows:
 • The mixing of wheat flour and water,
together with yeast and salt, and other
specified ingredients in appropriate ratios.
 • The development of a gluten structure in the
dough through the application of energy
during mixing.

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 • The incorporation of air bubbles within the
dough during mixing
• The continued ‘development’ of the gluten
structure created in order to modify the
rheological properties of the dough and to
improve its ability to expand when gas
pressures increase during fermentation.
• The creation and modification of particular
flavour compounds in the dough.

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• The subdivision of the dough mass into unit
pieces.
• A preliminary modification of the shape of
the divided piece.
• A short delay in processing to further modify
physical and rheological properties of the
dough pieces.
• The shaping of the dough pieces to their
required shape.

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• The fermentation and expansion of the shaped
dough pieces during proof.
• Further expansion of the dough pieces and
fixation of the final bread structure during
baking.
• Cooling and storage of the final product
before consumption

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 Types of Bread
There are three main kinds of bread in the
world:
 Those that rise highest and so have to be
baked in pans
 Those with a medium volume, like rye
and French breads
 Those that hardly rise at all and
consequently are called flatbreads

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 Wholemeal Bread
 Mostly have 90% or more wholemeal flour in
the recipe used, and any level of wholemeal
flour mixed with white flour
 Processing of these differs in two ways from
that of white bread:
1. During mixing, the amount of water added
to make an optimum dough consistency needs
to be increased because the bran in the
wholemeal absorbs more water

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2.The dough is weaker because the bran
particles break up the strong protein bonds in
the bread dough, and this weakens the dough
structure.This means the dough could collapse
when it rises
 Extra protein, called gluten, is added to make
the dough stronger and stop it collapsing
 Wholemeal bread contains higher
concentrations of minerals and vitamins than
white bread as it retains the bran and germ of
the wheat
 It is an excellent source of dietary fibre,
containing twice that of white bread and more
than multigrain breads

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 Multigrain Bread
 Mixed or multigrain breads are made from a
mixture of wholemeal, white or rye flour
 May contain wheat germ, honey, gluten, non-
fat milk solids, cracked and whole grains of
wheat and other cereals such as rye, oats, corn,
barley, rice millet and triticale

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 A wide choice of multigrain breads can be
achieved by blending various grains, vegetable
pieces, nuts, seeds, fruit and spices
 There are "light" and "heavy" multigrain
breads
 "Light" multi-grains have an openness similar
to white bread, with small kibbled grains, oats
or other wheat mixed through the bread

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 "Heavy" multigrain breads are characterized
by small volume, dense texture and a high
grain content
 "Light" breads are similar to white bread in
terms of composition, whereas "heavy" breads
are similar to or denser than wholemeal bread
 Multigrain bread contains whole grains of
different types

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 Kibbled Bread
 Contains kibbled grain, the grain that has been
broken into smaller pieces
 Many types of grain can be added to the bread
including rye, barley, oats, corn, millet, soya,
alfalfa and rice
 The grain should be soaked in water for
several hours before mixing because un-soaked
grain in bread is hard enough to break teeth
 This bread also needs extra protein (gluten) to
make the dough stronger and hold up the extra
weight of the grains

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 Fruit Bread
 Fruit breads use a normal bread recipe to
which fruit and often sugar are added
 Popular fruits used are raisins, currants,
dates, orange peel and dried fruits such as
apricots
 Hot cross buns and many fruit breads, also
have spices added
 Ingredients used to enhance appearance and
flavor of breads include cinnamon, nutmeg,
egg wash and sugar/water wash

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 Hearth Breads
 Some well known hearth breads include
French sticks (bagettes) and Vienna bread
which were traditionally baked directly on the
hearth, that is, the brick floor of the oven
 Some bakeries overseas place brick or stone
floors in their ovens so they can make this a
selling point
 The oven for hearth breads requires steam to
make the bread crusty

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 Special pans and baskets are now used to give
loaf varieties a different shape and distinctive
appearance
 Mostly hearth breads are permitted to contain
only wheat flour, water, yeast and salt
 Bread with only these ingredients and without
fats or emulsifiers will not keep for long

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 Flat Breads
 The earliest breads made by humans
 The most basic are still a mixture of flour,
water and salt kneaded into a pliable dough
before being shaped by hand and baked
 Wheat is the most popular choice of grain
although barley, millet, corn, oats, rice and rye
are used to make various flatbreads

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 Flatbreads can be single or double layered:
 Single layered flatbreads can be made without
yeast from a firm dough, e.g. tortillas from
Mexico, or from runny mixtures poured onto a
hotplate
 Alternatively they can be leavened (risen by a
process of yeast fermentation), as with the
baladi from Egypt
 Double layered flatbreads are leavened (with
fresh yeast or a sourdough remnant of a former
mix) and risen twice before baking

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 Baking at a very high oven
temperature seals steam
inside the bread, causing it
to blow up like a football
during the baking
 This forms a pocket that can
later be filled with other
food
 Egyptian pita bread is a
good example of this pocket
bread

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 Pita bread is a popular flatbread throughout
the Middle East that has moved into Western
cooking
 Flat breads are made throughout most of the
world. Examples are pita (from the Middle
East), chapati and naan (Pakistan), tortilla
(Mexico) and focaccia (Italy)
 The bread may be leavened (have a raising
agent of yeast or sourdough) or unleavened

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 There are two ways of shaping flat breads:
 The dough can be sheeted (rolled thinly) and
cut to shape
 The bulk dough can be divided into pieces,
rounded and then sheeted
 Pita bread is made with a mixture of flour,
salt, yeast and water
 Fermentation time is short so the dough does
not rise

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 When baked, heat quickly
seals the top and bottom
surfaces and the rapid
expansion of gases between
them tends to blow the crusts
apart forming the pocket
 Naan is also a leavened
bread that is baked by placing
flattened pieces of dough
onto the walls of shaped oven

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 These breads are usually baked in an extremely
hot oven with temperatures of 450°C - 600°C
 Chapati is an unleavened round flat bread from
Pakistan with most meals, wrapped around meat
or vegetables
 Tortillas are an unleavened flatbread from Mexico
made from corn flour or wheat flour
 They can be soft or crisp, depending on how long
they are baked
 When they are soft they are used as burritos and
when crisp are served as tostadas or corn chips

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 Bagels
 These are round, chewy rolls about 10
cm in diameter with a hole in the
middle
 They are in fact much like a doughnut
in appearance, but the resemblance
ends there (or it should!)
 The taste and texture of the bagel is
very different to the doughnut
although they have been referred to as
'cement doughnuts' or doughnuts with
rigor mortis

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 White Bread
 One of the most popular bread varieties
 It is made with a basic yeast dough of
wheat flour (usually all-purpose or
bread flour)
 There are many types of white bread
based on slight variations of the basic
recipe
 Most white breads feature a fine texture
and close grain, which makes slicing
easy
 Commercially prepared white bread is
usually sliced before packaging and is
most often known as sandwich bread

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 Rye Breads
 Rye bread is a wholemeal bread
made from rye or a mix of rye and
wheat flour
 It was originally developed in
Europe and is made in a wide variety
of styles and shapes
 Rye flour is different from ordinary
wheat flour
 It contains only small amounts of
dough strengthening proteins,
therefore producing weak dough

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 Rye flour also has more amylase
enzyme which breaks down starch
into sugars
 Rye doughs are made with less
water than dough from ordinary
flour, so they are stiff and keep their
shape
 Moulding, proving and baking also
need to be modified to handle the
weak, sticky dough
 As with most grain and meal breads,
some white flour or gluten can be
used to improve the dough strength

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 The traditional way of making this
bread includes several proving
stages to raise the acidity and kill
the amylase
 This stops the bread being doughy
and sticky
 The sour dough method is the
most popular means of making
bread the traditional way

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 Keeping Qualities of Rye Breads
 The lower pH of rye breads especially those
made with sour doughs inhibit the microbial
growth and confers a longer shelf life than the
commonly seen wheat breads
 The shelf life may be further increased by
pasteurization or sterilization
 This is carried out on the wrapped product so
the film must be heat stable and have good
barrier properties

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 The condensation formed within the film is
reabsorbed by the product and has no adverse
effect on quality
 The process may cause darkening of the
product but it is less important as the product
is already of dark color
 All types of ovens are used for the sterilization
process
 After the treatment the shelf life of the bead
may be extended to 24 months

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 A Wheat Kernel Up Close
 Endosperm 83% of kernel
 Bran 14.5 % of kernel
 Germ 2.5 % of kernel

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 The kernel consists of three distinct parts
 Bran, the outer covering of the grain
 Germ, the embryo contained inside the kernel
 Endosperm, the part of the kernel that
makes white flour
 During milling, the three parts are
separated and recombined accordingly to
achieve different types of flours.

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 Summary of the Six Basic Classes of Wheat
Used in Bakery Products
 Class : Hard Red Winter
Characteristics : Wide range of
protein content, good milling and
baking qualities
Uses : Bread, rolls, some sweet
goods and all purpose flour
 Class: Hard Red Spring
Characteristics : Highest percentage
of protein, superior milling and
baking qualities
Uses : Excellent bread wheat

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 Class : Soft Red Winter
Characteristics : High yielding,
relatively low protein
Uses : Flat breads, cakes,
pastries, and crackers
 Class : Hard White Winter
Characteristics : Milder, sweeter
flavor than red wheats; equal
fiber and similar milling and
baking qualities as red wheats;
differs in "color" genes
Uses : Yeast breads, hard
rolls, bulgur and tortillas

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 Class : Soft White Winter
Characteristics : Same as hard
white winter, low protein, high
yielding
Uses : Cakes, crackers, cookies,
pastries, quick breads, muffins,
and snack foods
 Class : Durum
Characteristics : Hardest of all
wheats
Uses : Semolina flour for
pasta production

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 Bread Ingredients

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 Bread Formula
 Minimum formula for bread is flour, yeast, salt
and water
 Other ingredients often used in the formula
are fat, sugar, milk or milk solids, oxidants,
enzymes, surfactants and additives to protect
against molds
 Each of the ingredient performs a special
function in the production of bread loaf

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 Flour
 Flour is the product obtained by
grinding wheat kernels or “berries.”
 Major structural component to
form viscoelastic dough to retain
gas
 Usually hard wheat with relatively
high protein content is preferred for
bread making
 The flour components play
important role in the preparation of
good quality bread

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 Nutritional Value of Flour
 Wheat flour is an excellent source of complex
carbohydrates.
 Other than gluten flour, all types of wheat
flour derive at least 80 percent of their calories
from carbohydrates.
 Depending on the flour type, the percent of
calories from protein ranges from 9 to 15 percent,
except from gluten, which has 45 percent protein
content.

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 In addition, wheat flour provides from 3 g
(cake flour) to 15 g (whole-wheat flour) of
dietary fiber per 1- cup serving.
 Wheat flour contains B-vitamins, calcium,
folacin, iron, magnesium, phosphorus,
potassium, zinc, minimal amounts of sodium and
other trace elements.
 Calories from fat are never more than 5
percent.

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 Wheat Flour Types Used In Bakery
Products
 White Flour
 All-Purpose Flour (8-11% Protein)
 Bread Flour (12-14% Protein)
 Cake Flour (7-9% Protein)
 Self Raising Flour
 Pastry Flour (8-9% Protein)
 Whole Wheat Flour
 Gluten Flour (40-45% Protein)

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 White flour is the finely ground endosperm
of the wheat kernel.
 All-purpose flour is white flour milled from
hard wheats or a blend of hard and soft wheats.
 It gives the best results for many kinds of
products, including some yeast breads, quick
breads, cakes, cookies, pastries and noodles.
 All-purpose flour is usually enriched and
may be bleached or unbleached. Bleaching
does not affect nutrient value.
 Protein varies from 8 to 11 percent.

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 Bread flour is white flour that is a blend of
hard, high-protein wheats and has greater
gluten strength and protein content than all-
purpose flour.
 Unbleached and in some cases conditioned
with ascorbic acid
 Protein varies from 12 to 14 percent.
 Bread flour is milled primarily for
commercial bakers

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 Cake flour is fine-textured, silky flour
milled from soft wheats with low protein
content.
 It is used to make cakes, cookies, crackers,
quick breads and some types of pastry.
 Cake flour has a greater percentage of
starch and less protein, which keeps cakes
and pastries tender and delicate.
 Protein varies from 7 to 9 percent.

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 Self-rising flour, also referred to as
phosphated flour, is a convenience product
made be adding salt and leavening to all-
purpose flour.
 It is commonly used in biscuits and quick
breads, but is not recommended for yeast
breads.
 A combination of sodium bicarbonate
together with a suitable acid ingredient will
produce a flour for a variety of uses, including
manufacture of batters, cakes and scones

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 By varying the acid type the point in the
process when the CO2 is evolved can be varied
 Mono-calcium phosphate results in 60% CO2
generation at the time of mixing and 40%
during baking
 If the acid is changed to sodium aluminium
phosphate then this can be changed to 30% at
mixing and 70% during baking stage
 The requirement for heat to be applied before
the majority of the CO2 is liberated can be
useful if the product is required to stand
before baking or if extended shelf life is
required

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 Pastry flour has properties intermediate
between those of all-purpose and cake flours.
 It is usually milled from soft wheat for pastry-
making, but can be used for cookies, cakes,
crackers and similar products.
 Pastry flour differs from hard wheat flour in
that it has a finer texture and lighter
consistency.
 Protein varies from 8 to 9 percent

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 Semolina is the coarsely ground
endosperm of durum, a hard spring wheat
with a high gluten content and golden color.
 Semolina is usually enriched and is used
to make couscous and pasta products such as
spaghetti, vermicelli, macaroni and lasagna
noodles.
 Except for some specialty products, breads
are seldom made with semolina.

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 Whole wheat, stone-ground and graham
flour can be used interchangeably; nutrient
values differ minimally.
 Either grinding the whole-wheat kernel or
recombining the white flour, germ and bran
that have been separated during milling
produces them.
 Durum wheat is commonly sold either as
finely ground flour, called durum flour, or as a
coarser granular product, called durum semolina
or simply semolina.
 It is also high in yellow carotenoid pigments

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 Their only differences may be in coarseness
and protein content. Insoluble fiber content
is higher than in white flours.
 Gluten flour is usually milled from spring
wheat and has a high protein (40-45 percent), low
starch content.
 It is used primarily for diabetic breads, or
mixed with other non-wheat or low-protein
wheat flours to produce a stronger dough
structure.
 Gluten flour improves baking quality and
produces high-protein gluten breads.

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 Triticale
 It is the first man-made cereal, being a
crossbreed between wheat (Triticum) and rye
(Secale)
 Have protein contents in the range of 10.7-
16.3%
 Amino acid balance is nutritionally superior to
that of wheat with an average lysine content of
3.7%
 Major incentive for incorporating triticale in
bakery products is its higher protein content
and lysine content as compared to wheat

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 However the protein advantage is negated by
the low flour extraction rates obtained with
most triticale cultivars
 Extraction rates for triticale range from 56.4-
64.0% as compared to 66.8-73.0% for wheat
 Triticale flour doughs are more extensible and
less elastic than wheat flour doughs
 Triticale proteins resemble rye protein more
than wheat proteins
 Triticale flours are relatively high in -amylase
activity, a trait they inherit from the rye parent

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 The water binding capacity of starch in triticale
doughs is reduced by the dextrinizing action of the
amylase and this has an adverse effect on the
flour’s baking quality
 Triticale malt added to wheat flour doughs
increases loaf volume and improve crumb grain
and crust color
 Proteolytic activity may be 20 - 53% higher than
wheat flour
 Lipid content of triticale endosperm flour range
between 1.72 - 2.24% compared to 1.33 - 1.56% for
rye and 1.53 - 1.57% for wheat
 Triticale lipids occur in a greater proportion as
bound than as free lipids

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 The free lipids contain 83-89% nonpolar
triglycerides and 11-17% polar digalactosyl
diglycerides and phosphatidyl cholines
 Bound lipids contain 27-39% nonpolar and 61-73%
polar components
 Neither the quantity nor the general chemical
composition of triticale lipids is intermediate
between the analogous components of the wheat
and rye parents
 Triticale flours yield doughs that lack smoothness
and pliancy of wheat doughs
 Generally Triticale flours doughs are not
considered suitable as the sole flour ingredient in
bakery products

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 Malted Grain Flour
 The addition of malted grains, either kibbled
or flaked, together with additional malt flours,
either diastatic or non-diastatic produces very
attractive bread with exceptional flavor
characteristics
 Other flours include wheat germ flour etc. and
flour blends containing other cereals e.g. rye,
oats and maize

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 Brown flour
 If white flour has extraction rate of 76-78%
then brown flour has equivalent of about 85-
90%
 Produced during milling process by feeding
back 10-15% of selected bran stocks into a white
flour
 Also produced by mixing whole wheat flour
and white flour in the ratio of 50:50

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 Particle size of bran is important to obtain best
performance
 Coarse bran gives good visual effect both in
the crumb and on the crust, however too much
coarser bran can result in an open and
unattractive structure
 Very fine bran on the other hand can have
deadening effect on the bread, resulting in a
bland, small loaf with a dull gray crumb

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 Wheat Flour Terminology Used In
Bakery Products
 The Food and Drug Administration inspects
and approves the use of flour treatments and
additives that are used to improve the storage,
appearance and baking performance of flour.
 The treatment additives are in no way harmful.
“Enriched” flour supplemented with iron and
four B-vitamins (thiamine, niacin, riboflavin and
folic acid) and may be with calcium.
Reconstituting the nutritional status of a
processed food ingredient to match that of the
original raw materials.

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“Fortified” implies that something is added to a
product that makes its nutritional status higher
than the product made from “unprocessed”
raw materials. i.e. Cereals.
“Pre-sifted” flour is sifted at the mill, making it
unnecessary to sift before measuring.
“Bromated” flour is largely discontinued in the
United States. Ascorbic acid is now being added
to strengthen the flour for bread dough’s.

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“Bleached” refers to flour that has been bleached
chemically to whiten or improve the baking
qualities. It is a process which speeds up the
natural lightening and maturing of flour.
“Unbleached” flour is aged and bleached
naturally by oxygen in the air. It is more golden
in color, generally more expensive and may not
have the consistency in baking qualities that
bleached flour does. Unbleached is preferred for
yeast breads because bleaching affects gluten
strength.

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“Patent” flour, bleached or unbleached, is the
highest grade of flour. It is lower in ash and
protein with good color. Market-wise, it is
considered the highest in value and mostly
used by bakers.
“Organic” or chemical-free flour is not
standardized, so its definition varies from state
to state. It may be grown and stored without the
use of synthetic herbicides or insecticides. It
may also mean no toxic fumigants were used to
kill pests in the grain and no preservatives were
added to the flour, packaging, or food product.

70. 70
 Functions of Flour In Bakery Products
 Provides Structure
 Flour is one of two bakeshop ingredients
that contribute to the toughening or structure
building in baked goods, eggs being the
other.
 Structure allows products to hold a new,
larger size and shape as gases expand and
leaven.
 It prevents products from collapsing once
they are cooled and removed from the pan.

71. 71
 Gluten and starch are responsible for much
of the structure-building properties of flour.
 While not as important as gluten and starch,
pentosan gums also contribute to flour
structure.
 Gums appear either to form their own
structure or to interact with gluten.
 Which of these structure builders—gluten,
starch, or gums—is most important to a
particular baked product depends on the type
of flour and the formula used.

72. 72
 Gluten certainly is most important for
developing structure in unbaked dough, but
starch is arguably more important to the
structure of the final baked product.
 On the other hand, products low in
moisture, like piecrust and crisp cookies,
inevitably rely on gluten alone for structure,
because starch gelatinization cannot occur in
the absence of sufficient water.

73. 73
 Absorbs Liquids
 Ingredients like flour that absorb liquids are
also called driers. Starches, proteins, and gums
are the three main components in flour that
absorb moisture (water) and oil, helping to
bind ingredients together.
 Same components that form structure are also
driers.
 The difference is that all proteins in flour—not
just glutenin and gliadin—absorb moisture, while
only glutenin and gliadin form structure.

74. 74
 The absorption value of flour is an important
quality factor in bread baking.
 It is defined as the amount of water absorbed
by flour when forming bread dough.
 High absorption values are desirable in bread
baking because the added moisture slows staling.
 Higher water absorption also means that less
flour is needed to make a loaf of bread, so if cost
is a factor, this is an important point.

75. 75
 Water absorption values of most bread flours
range around 50–65 percent.
 While doughs that absorb more water typically
have a higher protein content.
 Why Do Flours Differ in Absorption Values?
 By one estimate, almost half the water in
bread dough is held by starch, about one-
third by flour proteins, and close to one-
quarter by the small amount of gums in
white flour.

76. 76
 Starch absorbs most of the water in doughs
because there is so much starch in flour.
 Yet, the best way to predict which of two
flours will absorb more water is by comparing
the amount of protein each contains.
 Proteins, including gluten-forming proteins,
absorb fully one to two times their weight in
water, while starch absorbs only about one-
quarter to one-half its weight in water.

77. 77
 This means that a small increase in protein
has a noticeable increase in the amount of
water absorbed in doughs.
 High-gluten flour absorbs more water than
bread flour, and bread flour absorbs more than
pastry flour.
 This prediction works as long as the flour is
not bleached with chlorine or otherwise treated.
 Chlorine changes starch, so that it absorbs
more water.

78. 78
 Flour components and water absorption
 Four flour components absorb water; protein,
native starch, damaged starch and pentosans
Components Water/g of
component
Amount/
100g flour
Absorption/
100g flour
Protein 1.3 12 15.6
Intact starch 0.4 57 22.8
Damaged
starch
2 8 16
Pentosans 7 2 14

79. 79
 The native starch is relatively impermeable to
the water due in part to the lipids and proteins
found on the surface of the granules, derived
from cell walls of the amyloplasts of the
ripening wheat berry
 While native starch is the largest single
contributor to the absorption, this is due to its
preponderance in the flour
 During baking these granules swell, gelatinize
and become hydratable main water binding
species in baked bread

80. 80
 Most damaged starch is formed during
milling, during which the particles are
subjected to high pressure
 Due to high pressure exerted some of the the
starch granule are left with cracks and fissures
 Water penetrate through these cracks and
move towards interior where it interacts with
the amorphous regions

81. 81
 Hard wheat flours have higher damaged
starch content (6-12%) as compared to the soft
wheat flours (2-4%) as more more pressure
used to break up hard wheat
 The damaged starch is more susceptible to
amylase attack
 During proofing , digestion of the damaged
starch decreases its water holding capacity,
releasing more water into dough matrix and
increasing pan flow

82. 82
 Contributes Flavor
 Wheat flours have a relatively mild, slightly
nutty flavor that is generally considered
desirable.
 Clear flour, for example, with its higher
protein and ash content, to have a stronger
flavor than a fancy patent flour, like cake
flour.
 Whole wheat flour to have the strongest
flavor of all.

83. 83
 Contributes Color
 Flours vary in color. For example,
 Regular whole wheat has a nut-brown color
 Whole white wheat flour has a golden color
 Durum has a pale yellow color
 Unbleached white flour a creamy color
 Cake flour a stark white color.
 These colors carry over to the color of baked
goods.

84. 84
 Flour also contributes protein, small
amounts of sugar, and starches for Maillard
browning—the breakdown of sugars and
proteins—to a dark color on crusts.
 High-protein flours typically undergo
more Maillard browning than low-protein
flours.
 Adds Nutritional Value
 Essentially all flours and grain products
contribute complex carbohydrates (starch),
vitamins, minerals, and protein.

85. 85
 However, the protein in wheat is low in lysine,
an essential amino acid.
 This means that wheat protein is not as
nutritionally “complete” as egg or milk protein
and is best supplemented with other protein
sources for good health.
 White flour is a poor source of fiber, but whole
wheat flour and whole white wheat flour, being
whole grain products, are good sources of
insoluble dietary fiber from the bran, important
in the diet

86. 86
 Flour Quality for Breadmaking
 Breadmaking requires flour of specific
characteristics
 A flour suitable for the production of cookies
may not be suitable for breadmaking
 Being good for one use may not automatically
mean it is not not good for another
 Normally hard wheat flour with protein
contents about 10-14% is considered to be good
for the production of good quality bread

87. 87
 Wheat flour components can be classified into
six groups
 Starch
 Storage (Gluten) proteins
 Non starch polysaccharides (NSP)
 Lipids
 Water soluble proteins
 Inorganic compounds
 Wheat Flour Components

88. 88
 Starch
 Largest portion of flour, making up to 65% of
ordinary flour (14% moisture basis)
 Starch comprises about 25% amylose and 75%
amylopectin
 Amylose is linear chain of α-1,4 linked glucose
units with a molecular weight in the range of
100,000 Da
 Amylopectin is a branched structure,with
molecular weight of 20,000,000 Da

89. 89
 Native starch exists in the form of granules
and has high degree of crystallinity,
evidenced by birefringence
 The damaged starch granules absorb about
four times as much water as intact granules
and increase dough water absorption
 Also, the damaged starch is more susceptible
to the action of α-amylase than intact starch
 Starch is very much important in the final
structure of the bread as well in bread-staling

90. 90
 Gluten
 The hydrated glutelins (glutenins) and
prolamines (gliadins) formed when the dough
is mixed with water
 Of the total wheat flour protein, , one sixth is
soluble protein
 Thus a flour having 12% protein content
contains only about 10% gluten
 Gluten is very important in the retention of
gas, produced during fermentation therefore
contributes to the final bread volume

91. 91
 What Is Celiac Disease?
 Celiac disease is a disease of the intestinal tract
brought about by the consumption of gluten
(more specifically, the gliadin in gluten).
 When people with celiac disease consume
gluten—even very small amounts of it—their
bodies react by damaging the small intestine,
where nutrients are absorbed by the body.
 Without proper absorption of nutrients, people
with celiac disease—also called celiac sprue or
gluten intolerance—become malnourished.

92. 92
 They may develop a range of symptoms
related to intestinal distress or to poor
nutrition.
 Because people with celiac disease cannot
tolerate any amount of gluten, they must adhere
strictly to a gluten-free diet for their entire lives.
 This means that they cannot consume any
products that contain wheat. They also cannot
consume any rye or barley, and oats may also be
a problem for many.
 In place of wheat flour, gluten-free products
usually contain some combination of rice, soy,
potato, and tapioca flour.

93. 93
 Pentosans
 Represent only 2-2.5% of flour, but have a
disproportionate influence on dough properties
 Also called hemicellulose
 The term pentosans used because 80% of the
sugars present are pentoses, D-xylose and D-
arabinose
 The backbone is xylan chain containing β-1,4
linked D-xylose units to which other sugars are
attached with α-1,3 linkages

94. 94
 About 65% of the pentosans are water
insoluble that are exclusively xylans
 The water soluble pentosans are half
arabinoxylans and half arabinoglactans
 Pentosans can absorb water several times of
their weight
 During dough mixing the feruloyl moieties
attached to pentosans are attached to gluten via
addition of sulfydral groups across the
activated double bond, generating crosslinks
and enhancing dough elasticity

95. 95
 Lipids
 Wheat flour contains about 2.5% lipids, of this
1% are non polar (triglycerides, diglycerides,
free fatty acids and sterol esters)
 Main groups of polar lipids are glactosyl
glycerides (0.6%) and phospholipids (0.9%)
 During mixing both classes of lipids are
complexed with gluten and become relatively
unextractable with any of the usual solvents

96. 96
 Flour lipids have little effect on the mixing
requirements however, addition of the
surfactants strengthens dough and increases
mixing time
 Lipids have major influence on the baking
performance of bread, especially with respect
to oven spring and the keeping quality of the
finished product

97. 97
 Water Soluble Proteins
 The water soluble fraction comprises albumins
and globulins as well as water soluble
pentosans and are about 2-3% of the total flour
weight
 The proteins include enzymes, enzyme
inhibitors, lipoproteins, lectins and globulins
 Among the enzymes, β-amylase acts on starch
and releases maltose that serves as fermentable
sugar for the yeast during proofing of the lean
doughs

98. 98
 Inorganic Compounds
 Wheat flour contains about 0.5% ash
 The inorganic material has little effect on the
dough formation
 The addition of salts, however, increases the
resistance of dough to the mechanical mixing
and decreases water absorption due to the
enhanced gluten aggregation

99. 99
 Shortenings
 An optional ingredient that functions to
enhance the product's general palatability
rather than define its character
 When used as bread ingredient performs the
following functions:
 Tenderizing & imparting shortness to the
crumb structure
 Aiding in the aeration of the product
 Stabilizing batters & creams by
emulsification

100. 100
 Improving the over-all palatability
of the product
 Extending the keeping quality or
shelf life of the finished product
 Improve the flavor & color of
product
 Improve the volume of the final
product
 Increase the calorific value

101. 101
 Shortenings coat the flour proteins or water-
proof them, contributing to tender baking
recipe by reducing their contact with the
moisture in the recipe and preventing gluten
from forming
 They also shorten the length of the gluten
strands when the flour is stirred with that
moisture (that's why they're called
"shorteners"), preventing a tough baked good
or tenderize
 Fat coats the flour particles so the elastic
formation slows down; it makes the gluten
strands slippery so the gas bubbles can move
easily; and it gives the final recipe a finer grain

102. 102
 Generally, when we refer to "moist" in a baked
product, we refer to the fat content
 In traditional baking, where solid fats are
creamed with crystalline sugar, tiny air cells are
incorporated into the batter, so the baked good
will have a fine, aerated texture
 When a shortener is removed or reduced, it
increases the chances that the end product will
lack flavor and be tough and full of tunnels

103. 103
 Different types of fat do different jobs in
baking. A well-known baking fat, butter makes
a very important flavor contribution, whereas
margarine does not have as fine a texture and
taste
 Fat can be found in other baking ingredients,
such as the egg yolk which serves as both a
tenderizer and emulsifier due to its fat and
lecithin content
 Oils do not act as shortener because these are
liquid and won't cream with crystalline sugar
in the same way that solid fat does

104. 104
 Oils tend to coat each particle of flour, which
causes a lack of contact of moisture and helps
prevent gluten development
 It reduces dryness and enhances flavor
 Shortening acts as a lubricant in the dough,
making the dough more pliable, prevents
stickiness, and reduces the amount of dusting
flour necessary during the make-up process

105. 105
 When shortening is used, the dough expands
more easily and smoothly
 In the baked product it makes the crust more
tender, improves the keeping quality and
produces a crumb that is soft and chewy
 Because of the cutting effect on the bran in
whole-wheat flour, it is almost impossible to
produce a loaf of whole-wheat bread with
acceptable volume without using shortening in
the formula

106. 106
 Sources
 Bakery shortenings come from two sources:
 Animal sources
 Lard, tallow, butter
 Rarely used now a days due to limited supply
 Plant sources
 Hydrogenated plant oils e.g. sunflower etc.
 Have superior physical properties than the
animal fats

107. 107
 Shortening Types
 General purpose shortenings
 Designed to function optimally in a wide
variety of applications
 Produced from a hydrogenated base oil with 4-
12% hard fat addition to increase their plastic
range
 Their solid contents fall within range of about
30% at 10 oC to 12% at 38 oC
 Their iodine value varies between 60-75

108. 108
 Free fatty acid content is just about 0.04%
 The melting point of these shortenings fall
within the limits of 44-51 oC
 High emulsifier shortenings
 Designed for the production of cakes
containing high moisture & sugar content &
possessing superior tenderness, grain, &
moisture retention
 The desirable functional properties are
obtained by the addition of mono &
diglycerides that exhibit pronounced surface
active properties & effectively promote the
uniform distribution of the fat in doughs,
batters & icings

109. 109
 The fine dispersion of the fat confers superior
strength on the batter and permits the use of
higher ratios of sugar & liquid than is
otherwise possible with ordinary fats
 These shortening are therefore referred as
high ratio, high absorption or
superglycerinated shortenings
 Exclusively used in the cakes, icings, sweet
goods and similar products

110. 110
 High stability shortenings
 Used in the production of biscuits & crackers
that must possess an extended shelf life, and
frying operations in which the fat is exposed to
high temperature for prolonged periods of time
 These are hydrogenated to lower iodine value
in the interest of higher stability as their
application does not require high plastic range
 The absence of hard fat and hydrogenation
makes these shortenings hard and brittle at
temperatures below 16 oC and quite soft at
temperatures above 90 oC

111. 111
 Bread shortenings
 Formerly based on the animal fats but now
based mainly on vegetable oils
 Distinguished by being formulated with mono
and diglycerides and certain dough
conditioners that act to improve the volume,
grain and texture of the baked product and
retard the rate of subsequent crumb firming
 The most common surfactants in current use in
bread shortenings, aside from mono and
diglycerides are ethoxylated monoglycerides
and sodium stearoyl-2-lactylate

112. 112
 A number of additional emulsifiers and dough
conditioners may be used in dough
formulations, including lecithin, diaceytyl
tartaric acid esters of mono and diglycerides,
succinylated monoglyceride and sodium
stearoyl fumarate
 The use of hard, high melting mono- and
diglycerides in the bread shortenings is favored
as these prolong maximum softness in the
baked product
 Where more workable plastic shortenings are
needed, medium-melting emulsifiers are
selected for addition

113. 113
 Puff pastry fats
 Possess a broad plastic range and a tough
waxy texture with good extensibility to meet
the exacting requirements imposed by rolling,
folding and layering procedure employed in
pastry production
 Higher melting fats, while exhibiting superior
machinability and tolerance during the rolling
and folding operations tend to impart a
noticeable waxy aftertaste as they do not melt
in the mouth

114. 114
 The fats melting below 39 oC do not exhibit
this “palate cling” but are some what lacking in
the plasticity at higher temperatures and
require greater care during handling during
pastry production
 New hydrogenation techniques permit the
formulation of pastry fats that possess excellent
plasticity and structural properties at
temperatures of 4.4-32.2 oC
 Such fats are characterized by superior
palatability and mouth feel

115. 115
 Sweeteners
 Sugar used as sweetener serves a number of
roles:
 Besides its pleasant sweetness, sugar performs
a host of less-obvious and important functions
in baking
 Flavor Enhancement—Sugar "potentates,"
blends and balances flavor components, much
like a seasoning
 Solubility—Sugar is readily soluble in water.
The ability to produce solutions of varying
degrees of sweetness is important in
confectionery

116. 116
 Sugar’s capacity to produce a
supersaturated solution and then
crystallize when cooled is the basis for
rock candies
 The wonderful variety of
confectionery draws from ability to
vary sugar concentration, along with
temperature and agitation, to produce
different crystal sizes and textures
 Boiling Point Rise, Freezing Point
Depression—In solution, sugar has the
effect of lowering the freezing point
and raising the boiling point of that
solution

117. 117
 In shortening-based cakes, sugar raises, delays
and controls the temperature at which the
batter goes from fluid to solid, which allows the
leavening agent to produce the maximum
amount of carbon dioxide
 The gas is held inside the air cells of the
structure, resulting in a fine, uniformly-
grained cake with a soft, smooth crumb texture
 Hydrolysis (inversion)—In food processing,
hydrolysis decreases the tendency of sugar to
crystallize
 These are important properties in preparing
frozen desserts and candy, respectively

118. 118
 Caramelization
 Thermal decomposition—When
sugar is heated to a sufficiently high
temperature, it decomposes or
"caramelizes"
 Its color changes first to yellow,
then to brown, and it develops a
distinctive and appealing flavor and
aroma. The melted substance is
known as caramel
 The brown color of toasted bread is
the result of caramelization

119. 119
 Yeast Fermentation — Sugar is
consumed by yeast cells in a
thoroughly natural process called
"fermentation“
 Carbon dioxide gas is released,
and alcohol is produced, reactions
vital to bread rising and baking
 Browning (Maillard
reactions)—Color is also produced
in cooking when sugars and
proteins interact in complex ways;
this is known as the browning
(Maillard) reaction, important in
baking, candy making etc.

120. 120
 Texture Modification— Granulated white
sugar and brown sugar are integral to the
creaming process that incorporates air into batters
 When sugar is creamed with shortening in baked
goods, the irregularities of the of the sugar crystals
help create air pockets that contribute to a
uniformly fine crumb structure
 In gingersnaps and sugar cookies, the desirable
surface cracking pattern is imparted when sugar
crystallizes by rapid loss of moisture from the
surface during baking
 Bodying/Bulking Agent— Sugar imparts
satisfying texture, body, mouth feel and bulk to
baked goods and other foods

121. 121
 Preservative—By binding water, sugar acts as
a very effective, natural preservative
 Sugar is the preferred sweetener in cereal
coatings because of its ability to crystallize into
a frosty surface forming a hard, continuous
glaze that protects the product from air and
moisture, extending its shelf life
 Dispersant—In dry bakery mixes, sugar
prevents lumping and clumping when the mix
is hydrated
 Whipping Aid— In foam-type cakes sugar
enables the creation of a light foam that serves
as the basic structure of the cake

122. 122
 Humectant—When the sucrose molecule is
"inverted", by the application of heat, acids or
enzyme, the resulting fructose (especially) and
dextrose contribute a moistening property,
desirable in cakes, soft cookies etc.
 Microwave Properties— Sugar has unique
dielectric properties that enable it to produce
desired surface browning and crisping
 Sugar can function as a control agent to
minimize uneven heating

123. 123
 Quick Breads: Quick breads are prepared
with leavening agents that act more rapidly
than yeast
 Since most quick breads contain relatively
small amounts of shortening and little or no
sugar, they require special care in mixing to
obtain a tender baked product
 In preparing quick breads, the chance of
overdeveloping gluten because of the lack of
sugar is a constant risk

124. 124
 With sugar scant or absent, the flour and
liquid must be combined gently and stirred
only enough to just moisten the dry ingredients
 As the amount of sugar increases, the risk of
coarse, uneven grain and chewy texture caused
by overmixing decreases
 Yeast Breads: In small amounts, added sugar
helps yeast begin producing gas for raising yeast
dough
 Sugar in large amounts slows yeast
fermentation; in a very sweet dough the
rising time is longer

125. 125
 During the mixing phase, sugar absorbs a high
proportion of water, delaying gluten formation
 The delayed gluten formation makes the bread
dough's elasticity ideal for trapping gases and
forming a good structure
 Sugar contributes to the brown crust and
delicious aromatic odor of bread by Maillard
reaction
 Also, some of the yeast fermentation by-
products and proteins from the flour react with
sugar contributing to bread's color and flavor

126. 126
 Sucrose (Table Sugar)
 Has many functions in food other than
providing sweetness
 On average used @ 2%(on flour weight basis)
 Tenderizes dough and batter products and
helps the baked product to brown
 Moisture is retained better in sweetened
breads than in unsweetened breads
 It is the sugar in cookie dough that causes
spreading to occur during baking

127. 127
 Reducing the amount of sugar by more than
1/3 can cause loss of tenderness, moisture,
browning, and sweetness
 The volume may increase in a bread recipe
when sugar is reduced
 Fructose
 In crystal form is nearly twice as sweet as
sucrose and is more expensive
 Attracts more water than sugar therefore,
fructose sweetened products tend to be moister
 Baked products made with fructose will be
darker than if they were made with sucrose

128. 128
 Invert Sugar
 When sucrose is boiled with dilute acid or
passed through acid cation bed of ion exchange
system, it hydrolyses into fructose and glucose
 The glucose-fructose mixture has negative
optical rotation as compared to sucrose
(rotation reversed) so the sugar is called invert
sugar
 It is used in the bakery products due to its
hygroscopicity
 The baked goods containing large amounts of
invert sugar keep moist for longer time

129. 129
 Honey
 Comprises glucose, fructose, maltose
and sucrose
 It is sweeter than sugar because it
contains fructose & has a distinctive
flavor
 When using honey in place of sugar,
reduce the other liquid ingredients
 Even when liquid is reduced, a product
that contains honey will be moist
because the fructose absorbs moisture
from the atmosphere
 Too much honey may cause the product
to become too brown

130. 130
 Molasses
 Contain sucrose, glucose and
fructose as well as small amounts of
Vitamin B, calcium and iron
 Impart a dark color and strong
flavor to baked foods
 These are not as sweet as sugar,
therefore increase their amount to
substitute per unit weight of sugar
and reduce the amount of other
liquids in the recipe

131. 131
 Because molasses is more acidic than sugar, it
may be necessary to add excessive amount of
baking soda for molasses used in substitution
for sugar
 Imparts a dark color and stronger flavor to
baked foods
 Replace no more than 1/2 the sugar in the
recipe with molasses

132. 132
 Artificial sweeteners
 They provide sweetness to foods but lack the
browning, tenderizing, and moisture retaining
properties provided by table sugar
 Specially formulated recipes are often needed
to make a product with acceptable texture and
appearance when using artificial sweeteners
 Because the different low-calorie sweeteners
vary in sweetness and bulk, package directions
must be followed for the amount to use in place
of sugar

133. 133
 Saccharin
 It is a heat stable non-caloric sweetener
 In its pure form, it is 200-300 times as sweet as
sucrose
 Bulking agents are added to saccharin
products to aid in measuring
 Saccharin has a bitter aftertaste
 Aspartame
 Commonly known as Nutrasweet SM
 It is not heat stable so it is not appropriate for
baked goods

134. 134
 Acesulfame K (Sweet One SM)
 It is a very low calorie sweetener that is 200
times as sweet as sucrose
 It is heat stable so it can be used in baked
goods
 For improved texture in baked products, use
acesulfame K in combination with granulated
sugar
 It has no unpleasant aftertaste

135. 135
 Yeast
 All breads are not the same, some
bread is yeasted and some are
unyeasted
 Tortillas and pitas are flat and
dense and are called unyeasted
breads, while yeasted loaves of
sandwich bread are puffy and light
 Yeasted bread types are caused by
different species of yeast: Packaged
or baker's yeast or yeast cultivated
in a sourdough or sponge starter

136. 136
 It is responsible for leavening the dough,
creating the texture of the crumb, maturing the
gluten from the flour and providing the
characteristic yeast leavened flavor and aroma
 In order to function properly, all yeast needs
food (sugar), moisture and a warm
environment
 During fermentation, consume food and
release carbon dioxide, alcohol, and other
organic compounds
 C 6H 12O 6 → 2C 2H 5OH + 2CO 2

137. 137
2X Energy
 Fermentation
Maltose
Glucose
Pyruvate
Acetaldehyde
Ethanol
Acetyl CoA
Organic Acids Fatty Acids
Esters
Biosynthesis
Pre-cursers
Ketones
Fusel
Alcohols
O2
28X Energy
Respiration

138. 138
 The gas is the rising agent in bread, and the
other "waste" products create the subtle flavors
and texture that make a good loaf
 Yeast is very sensitive; too much heat will kill
it, and cold will stunt its growth
 Moist dough between 78-80 oF (25-29 oC) is an
ideal environment for yeast growth
 Since yeast is very sensitive to temperature,
temperature is a major factor in how fast yeast
multiples

139. 139
 Yeast is dormant and will not grow at 40 oF (5 oC)
and grows only slowly at 55 oF (13 oC)
degrees. Yeast dies instantly at 140 oF (60 oC) so
do not use water warmer than 120 oF (~50 oC) to
avoid accidentally killing the yeast
 Bread is baked when the internal temperature is
between 190-210 oF (88-99 oC)
 At higher temperatures than 78-80oF (25-29 oC),
the dough may rise too quickly creating a crumbly
texture to the bread
 At less, the bread will rise more slowly and will
have a higher alcohol content

140. 140
 Packaged yeast
 Also known in some circles as baker's yeast
 Baker’s yeast is one species of yeast from the
family Saccharomyces cerevisae, especially well-
suited for the baking process: saccharo
meaning sugar loving or feeding, myces
meaning mold, and cerevisae being a word that
was once used for beer
 It needs moisture, food, and the proper
environment to function properly

141. 141
 TYPES
 Dry yeast: The most popular type, such as
active dry yeast, is available in a dehydrated
form in premeasured packages in the baking
isle
 Others include: Instant Active Dry, Rapid Rise
and Bread Machine
 Cake yeast: is also known as fresh or
compressed yeast
 It is found in the form of a small, square shape
wrapped in foil in the refrigerator case

142. 142
 Active Dry Yeast
 It is called active to distinguish it from
Nutritional or Brewer's Yeast which is also dry
and NOT the same thing
 It is the most commonly available and most
widely used kind of yeast
 It is reliable and predictable and has been
grown for flavor and speed of growth
 It also adds a nice yeasty flavor to the bread

143. 143
 It is available in the form of tiny brownish
grains, larger than Instant Active Dry Yeast,
making it necessary to proof before using
 Recommended water temperatures will vary
by manufacturer between 100-115 oF
 These are clumps of dehydrated, pure yeast
cells that has been air dried into dormant
granules

144. 144
 In each yeast envelope, there are thousands of
living plant-like microorganisms, which are
finely ground and absorb moisture quickly to
convert the flour's starches and sugar into
carbon dioxide
 Active dry yeast will keep well beyond its
expiration date printed on the package for 1
year if unopened at room temperature and
even longer if frozen
 If frozen, you can use it directly without
thawing

145. 145
 If opened, active dry yeast will keep 3 months
in the refrigerator and 6 months in the freezer
 Keep yeast in its original container with the
opened flap folded closed in a re-sealable
plastic bag
 Stored at room temperature and opened
without a protective outer container it loses its
power at about 10% per month
 Always smell and proof yeast used beyond its
expiration date printed on the package

146. 146
 Instant Active Dry Yeast
 Also known as RapidRise or Quick-Rise brand
names and Bread Machine Yeast
 A newly developed strain of yeast that can be
mixed with the dry ingredients, as opposed to
being proofed (dissolved) and requires only
one rise
 Instant Yeast combines the qualities of both
Active and Fresh Yeast -- the first one known
for its convenience and the latter for its potency

147. 147
 These types of yeast also contain ascorbic acid
resulting in increased loaf volumes
 The particle size of Instant Active Dry Yeasts
are finely granulated to allow complete
hydration of the yeast cells during the mixing
process that become active the "instant" it
contact moisture
 While Instant Active Dry Yeast is especially
suited to the types of breads typically made in
bread machines, it also works for general hand
baking

148. 148
 It is added to the dry ingredients and then, the
liquid portion of the recipe's ingredients,
warmed to 120–130 oF are added to make a
dough
 Instant yeast will keep a year at room
temperature if unopened
 If opened, it will keep 3 months in the
refrigerator and 6 months in the freezer
 Keep yeast in its original container with the
opened flap folded closed in a re-sealable
plastic bag

149. 149
 Cake, Fresh or Compressed Yeast
 Cake yeast is available in the form of small,
soft and crumbly squares in a starch medium,
found in the refrigerated case
 It is considered to be potent and it imparts a
great flavor to the final loaf
 It can either be dissolved in water first or
crumbled into the dry ingredients
 This yeast is especially well suited to long rises
and sponges

150. 150
 Cake yeast must be kept refrigerated or frozen
because cake yeast is highly perishable
 It must be used before the expiration date if
stored in the refrigerator, but you have more
leeway if stored in the freezer
 It has a refrigerated shelf life of about three to
four weeks from the date of manufacture and
can be frozen up to three months
 Do not leave fresh yeast out of the refrigerator
for more than 30 minutes, close bag tightly after
each use

151. 151
 Cake yeast should be white or light brown in
color and crumble easily
 It should have a pleasant yeasty smell
 If it is dark brown, moldy, soft or gummy, it is
either spoiled or has been stored improperly

152. 152
 Bread Machine Yeast, Instant Active
Dry Yeast or Rapid Rise:
 "Bread machine yeast," also known as "instant"
yeast, requires no proofing
 It becomes active the "instant" it contacts the
liquid ingredients
 It is a special strain of yeast and is designed to
disperse more thoroughly through the dough
during mixing and kneading, well suited to
bread machines

153. 153
 It can keep several months in the refrigerator
and almost indefinitely in the freezer (no need
to thaw before using)
 The temperature of the water or liquid in the
recipe used has to be adjusted to 100-115 oF or
as recommended by the manufacturer

154. 154
 Functions
 Yeast works by consuming sugar and
excreting carbon dioxide and alcohol as
byproducts
 In bread making, yeast has three major roles
 We are familiar with yeast's leavening ability,
but it also helps to strengthen and develop
gluten in dough and also contributes to
incredible flavors in bread

155. 155
 Yeast Makes Dough Rise
 Yeast cells thrive on simple sugars
 As the sugars are metabolized, carbon dioxide
and alcohol are released into the bread dough,
making it rise
 The essentials of any bread dough are flour,
water, and of course yeast
 As soon as these ingredients are stirred
together, enzymes in the yeast and the flour
cause large starch molecules to break down
into simple sugars

156. 156
 The yeast metabolizes these simple sugars and
releases carbon dioxide and ethyl alcohol into
existing air bubbles in the dough.
 If the dough has a strong and elastic gluten
network, the carbon dioxide is held within the
bubble and will begin to inflate it, just like
someone blowing up bubble gum
 As more and more tiny air cells fill with
carbon dioxide, the dough rises and we're on
the way to leavened bread

157. 157
 Yeast strengthens bread dough
 When flour and water are stirred together,
two proteins in the flour -- gliadin and
glutenin -- grab water and each other to form
a bubble gum-like, elastic mass of molecules
that we call gluten
 In bread making, we want to develop as
much gluten as we can because it strengthens
the dough and holds in gases that will make
the bread rise
 Once flour and water are mixed together,
any further working of the dough encourages
more gluten to form

158. 158
 Manipulating the dough in any way allows
more proteins and water to link together
 Yeast, like kneading, helps develop the gluten
network
 With every burst of carbon dioxide that the
yeast releases into an air bubble, protein and
water molecules move about and have another
chance to connect and form more gluten
 In this way, a dough's rising is an almost
molecule-by-molecule kneading

159. 159
 When bread dough is punched down after its
first rise, it become smooth and gluten strong
 At this stage, mostly the dough is stretched
and tucked into a round to give it a smooth,
tight top that will trap the gases produced by
fermentation
 This very springy dough is let stand for 10-15
minutes
 This lets the gluten bonds relax a little and
makes the final shaping of the dough easier

160. 160
 Fermentation Generates Flavor in Bread
 The big molecules in proteins, starches, and
fats don't have much flavor, but when they
break down into their building blocks --
proteins into amino acids, starches into sugars,
or fats into free fatty acids -- they all have
marvelous flavors
 Fermentation breaks down large molecules
into smaller, flavorful ones
 At the beginning of fermentation, enzymes in
the yeast start breaking down starch into more
flavorful sugars

161. 161
 The yeast uses these sugars, as well as sugars
already present in the dough, and produces not
only carbon dioxide and alcohol but also a host
of flavorful byproducts such as organic acids
and amino acids
 A multitude of enzymes encourages all kinds
of reactions that break big chains of molecules
into smaller ones -- amylase and maltose into
glucose, proteins into amino acids
 As fermentation proceeds, the dough becomes
more acidic

162. 162
 This is due in part to rising levels of carbon
dioxide, but there are also more flavorful
organic acids like acetic acid (vinegar) and
lactic acid being formed from the alcohol in the
dough
 The acidity of the dough causes more
molecules to break down & the dough becomes
a veritable ferment of reactions
 Eventually, the amount of alcohol formed
starts to inhibit the yeast's activity

163. 163
 Factors Effecting Fermentation
 Yeast Growth
 During fermentation process yeast also undergoes
some growth and cell multiplication
 Dough with a yeast content of 1.67%, fermented at 80°
F (27° C), demonstrates no significant increase in
yeast-cell count during the first two hours of
fermentation with the actual rise in cell numbers being
on the order of 0.003%
 The most vigorous yeast growth can be observed
during the period between the second and fourth
hours of fermentation, when the yeast cell count may
increase by 26%

164. 164
 Between the fourth and sixth hours, the rate of
yeast multiplication declines again
 Other findings indicate that the smaller the
original quantity of yeast in the dough, the
greater the percentage increase in cell numbers
during the fermentation, with all other
conditions being held constant
 The lower yeast level, the competition for
nutrients is far less than at the higher yeast
levels. Thus, each yeast cell has access or at
least the opportunity for access to greater food
supplies during fermentation

165. 165
 Fermentative Adaptation
 When yeast is first added to the sponge or
dough, it is still in a relatively dormant state
 A number of studies have shown that yeast
requires about 45 min in a favorable
environment to attain full adaptation to
fermentation, although it begins to evolve
carbon dioxide and ethanol in a much shorter
time
 During this period of adaptation yeast exhibits
a high degree of sensitivity to both favorable
and unfavorable environmental influences

166. 166
 Adaptation is somewhat more readily
accomplished in sponge-dough than in
straight-dough systemsas the yeast-inhibitory
ingredients as salt, and high sugar levels are
normally withheld to enhance fermentation
 No such amelioration of the environment for
yeast is possible with straight doughs
 All other factors being equal, yeast adaptation
is perceptibly promoted by a plentiful supply
of moisture, e.g., in slack sponges and dilute
preferments

167. 167
 Since water serves as the indispensable
medium in which the metabolic processes of
yeast take place, its relative abundance
significantly accelerates the rate at which
these processes occur
 Stiff sponges and highly concentrated
preferments are usually marked by delays in
full yeast adaptation.

168. 168
 Sugar Utilization
 Yeast exhibits a variable preference for
different sugars
 It readily assimilates four sugars, namely,
sucrose (after hydrolysis to glucose and
fructose by yeast invertase or sucrase), glucose,
fructose, and maltose (after hydrolysis to
glucose by yeast maltase)
 In yeasted doughs, an increase in maltose
occurs during first stages of fermentation, until
the initial supply of glucose and fructose is
exhausted, after which the maltose content
gradually declines

169. 169
 Doughs prepared only from flour, water, yeast
and salt will initially contain only about 0.5% of
glucose and fructose derived from the flour
 This is adequate to start fermentation and to
activate the yeasts adaptive malto-zymase
system that is responsible for maltose
fermentation
 Fermentation is sustained by the action of a-
and beta-amylases of flour that convert the
susceptible damaged starch granules into
maltose

170. 170
 Damaged starch results from milling and its
level is normally much higher in hard wheat
flours than in soft wheat flours
 Quantitative calculations show that I g of yeast
will ferment about 0.32 g of glucose per hour
during a normal fermentation
 Since the second stage of fermentation
involves the conversion of maltose into ethanol
and carbon dioxide, the behavior of this sugar
in the fermentation process is of some
significance

171. 171
 This is especially the case since different yeast
strains have been shown to vary in their
maltase activity
 Experimental results have shown that a yeast
strain with low maltase activity needed 21 min
longer to produce two rises in a dough than did
another, high-maltase yeast
 Yeast strains also differ in their maltase
activity in different doughs

172. 172
 A single yeast strain may also exhibit variable
maltase activity under different test conditions
 The rate of maltose fermentation by yeast also
has been shown to be influenced by pH to a
much greater degree than is true of glucose
fermentation

173. 173
 Acidification
 The pH of doughs or preferments has little
effect on yeast fermentation, unless it drops
below 4.0
 In general, yeast activity is fairly constant over
a pH range of 4-6, which represents a 100-fold
change in acidity
 At the onset of fermentation, dough pH is
approximately 5.5-5.8

174. 174
 During the course of fermentation, it decreases
to 4.9-5.1, due to the production of carbonic
acid (CO2 dissolved in water) and other
organic acids
 This pH drop is resisted by the buffering
action of several dough ingredients
 Both flour and milk are excellent buffers and
help to maintain the pH range for optimum
fermentation

175. 175
 When water brews are used then chemical
buffers such as calcium carbonate, are added to
maintain a pH range of 4-6 during fermentation
 Dough fermentation, in addition to generating
alcohol and carbon dioxide, also produces
small amounts of a fairly large number of
organic acids
 The most prevalent are acetic, propionic,
butyric, isobutyric, valeric, isovaleric and
capriotic and acetic acid is the most prevalent
by far

176. 176
 The production of acetic acid is much higher in
breads made with a poolish or naturally
leavened than with a straight dough
 As maturation progresses and fermentation is
prolonged, the dough becomes richer in
organic acids, and this increase becomes
evident as a lowering of its pH
 The longer fermentation is allowed to
continue, the richer in organic acids the
medium becomes

177. 177
 This formation of acids is reflected in a time-
dependent decrease of pH and an increase in
titratable acidity in the fermenting medium
 A number of factors such as aroma, and
keeping quality are enhanced as a result of the
development lower pH (more acidic) dough
 The presence of salt in dough often
masks acetic acid and when the dough is
leavened with an unsalted preferment, the
acetic acid or vinegar odor appears a little more
rapidly, although it is still hardly perceptible

178. 178
 The pH is ultimately related to the level of
residual sugars present in the dough before
baking
 These residual sugars are the remainder of
those that fed dough fermentation
 They fulfill important functions during the
baking process
 The level at which they are present plays an
important role in the quality of the final loaf of
bread

179. 179
 Generally, a below average pH coincides with
a lack of residual sugars, which translates to a
deficiency in oven-spring, i.e. loaf volume,
crust coloration and crust thickness, aroma,
crust taste, crumb flavor, and keeping quality
 When the dough is leavened with
prefermented dough which undergoes an
excess of maturation or fermentation, it is good
practice to remedy the lack of residual sugar in
advance by adding from 0.1% to 0.2% malt
extract during mixing to reestablish the proper
sugar balance

180. 180
 The presence of an appropriate amount of
residual sugars in the dough at the time of
baking is extremely important
 It insures an active oven spring, assists in
dough development, and helps the loaves to
reach a normal volume
 Appropriate residual sugar levels contribute to
optimal crust color, which in turn, contributes
to the exterior appearance, the aroma and the
flavor of bread
 The accumulation of lactic acid in fermenting
dough is attributable primarily to the presence
of the genus Lactobacillus in both flour and
compressed yeast

181. 181
 In sourdough breads, acetic acid represents
about 50% of the total acids found, and five to
ten times that found in white (non-sourdough)
breads
 The pH of fermenting dough is more strongly
affected by the presence of ammonium salts in
yeast foods, especially if the ammonia is
present as the salt of a strong acid such as
hydrochloric or sulfuric acid
 Yeast readily assimilates ammonia as a
nitrogen source

182. 182
 Yeast Tolerance to Acidity
 Yeast exhibits a considerable tolerance to
extremes of pH, being able to maintain an
active fermentation in a 5% glucose solution in
the pH range of 2.4 to 7.4, but ceasing activity
at pH 2.0 or pH 8.0
 For optimum results, good practice dictates
that the pH of the fermenting medium be
maintained within the range of about 4.0 to 6
 More gradual declines in yeast activity were
encountered at higher pH levels, with
measurable effects showing up at pH values
over 6.0

183. 183
 Yeast has ability to maintain a relatively
constant activity over a 100-fold change in
hydrogen ion concentration (pH 4 to 6) as the
pH of the cell interior of the yeast remains quite
constant at about pH 5.8, regardless of any
relatively wide pH variations in the fermenting
medium
 The enzymes involved in fermentation thus
operate in an optimum pH environment within
the yeast cell that is largely unaffected by
external changes in pH

184. 184
 Fermentation time
 Temperature of the dough is an important
factor
 This factor determines the amount of time
yeast gets to act on the sugars present in the
ferment, whether it be a sponge, brew, or a
straight-dough
 While the rate of fermentation declines with
time at a constant temperature, it does not
completely stop
 However, the longer the fermentation time, the
higher the degree of fermentation

185. 185
 Fermentation temperature
 Like any other living cell, the various
enzymatic activities of the yeast cell are closely
tied to the temperature of the environment
 Therefore, higher ferment temperatures
increase yeast activity, and vice-versa
 Within the range of temperatures in which
yeast is operative, every one-degree rise in
temperature increases the rate of yeast
fermentation by 3-5%

186. 186
 Likewise, a decrease of 1°F will cause a similar
decrease in the rate of fermentation
 The temperature range for optimum yeast
fermentation is between 75°F-85°F
 The process of fermentation also generates
heat, and amount of heat generated is often
used by bakeries as an effective way to monitor
the degree of fermentation

187. 187
 Level of water
 Generally, stiffer doughs take longer to
ferment as compared to slacker ones
 With additional water, the soluble solids are
diluted and the osmotic pressure on the yeast
cells is reduced that causes an increase in yeast
activity and the overall rate of fermentation

188. 188
 Level of sugar and salt
 Yeast fermentation is retarded in the presence
of high concentrations of sugar and salt
 This inhibitory effect is related to the high
osmotic pressure gradient created outside of
the yeast cells due to high concentrations of
sugar and/or salt in dough
 A measurable decline in fermentation rate is
observed if sugar concentration exceeds 5%

189. 189
 This effect is more pronounced with sucrose,
glucose, and fructose than with maltose
 Flour contains approximately 0.5-1% of a
combination of sucrose, glucose, and fructose,
which are generally fermented within 1-1.5
hours
 Yeast turns to maltose for CO2 production
after these preferred sugars are exhausted
 Once that happens, the rate of fermentation is
limited by the amount of maltose being
hydrolyzed (broken down) in the dough

190. 190
 The availability of maltose is directly related to
the damaged starch content and amylase
activity of the flour
 Maltose is a disaccharide and is not broken
down into its constituent glucose molecules
until it is absorbed into the yeast cell
 Therefore, it exerts a lower osmotic pressure
than the monosaccharides and the readily
hydrolyzed sucrose
 Salt also inhibits yeast activity at levels above
1%

191. 191
 The normal usage of salt in most breads range
between 1.75-2.25% to obtain desired flavor of
the product
 Sometimes higher levels of salt are used as a
means of fermentation control
 Satisfactory fermentation rates can usually be
achieved in doughs containing high levels of
salt or sugar by increasing the amount of yeast
used

192. 192
 Minor ingredients
 Salt
 This not only adds flavor, but helps to bring
out the natural flavors
 Bread made without salt is quite bland flat &
almost inedible
 Never add it to the liquid in which the yeast is
dissolving as it inhibits yeast growth
 It also assists with the fermentation process by
strengthening the protein network so that it
traps more gas, which makes for a larger loaf

193. 193
 Eggs
 Add protein, color & loft
 They also add to the keeping quality of bread;
due to the preserving quality in the lecithin in
the egg
 If eggs are added in addition to required liquid
amount, then decrease liquid in the recipe
 Acidity regulators
 Used to increase the acidity in the dough;
which helps to prevent the growth of mould or
bacteria in the bread
 These regulators might be vinegar, acetic acid,
citric acid or sodium diacetate

194. 194
 Emulsifiers
 These improve the volume, texture, crumb
color & softness of the bread
 Also improve the slicing characteristics, the
amount of oven-spring (how much the dough
rises) & also helps in the prolonging of shelf life
 Lecithin is a common emulsifier, which is
produced commercially from the soya bean
 It may be added to bread recipes to help with
combining the mixture of water & vegetable
oils present in the dough
 Fats have the power of controlling how fast the
essential protein (gluten) network develops
during bread making & also can make the
dough easier to work with

195. 195
 Milk & milk powder
 Make bread rise higher, toast more evenly &
quickly
 Bread will have a finer texture & keep longer
 All milk types should be scalded (heat to just
below boiling), except canned milk, to kill
enzymes that interfere with the activity of the
yeast
 Milk proteins also compliment the protein in
wheat for added nutritional value

196. 196
 Buttermilk
 Make the dough tenderer & give a nice flavor
 Scalded like regular milk & use no more than
½ liquid requirement or it can make the bread
too tender
 Whey
 Rich in protein, minerals & milk sugar
 Aids in browning, adds nutrition, adds flavor
& slightly sweetens
 Good for promoting beneficial bacteria in
colon (like yogurt)

197. 197
 Malt & malt extracts
 Malt flour is made from carefully sprouted,
then kiln dried barley kernels
 Some malt extracts are used to give taste &
color to the bread; especially grain & whole-
meal breads
 Other malt flours can be used to produce sugar
from the starch in flour, due to amylase action,
so that the yeast has more sugar to work on,
they also help bread to stay soft & moist

198. 198
 Flour treatment agents
 A major flour treatment agent used is Ascorbic
acid (vitamin C)
 Helps to counteract the negative effects of
Glutathione
 Vitamin C will not only help prevent the
gluten bonds from breaking down; but will
help repair gluten bonds that have already
been broken
 It helps sustain the leavening of bread loaves
during baking
 It also promotes yeast growth causing yeast to
work longer & faster & helps produce the
acidic atmosphere in which yeast grows best

199. 199
 Enzymes
 These are used to speed up the breakdown of
starch into sugars that the yeast can use, which
will help the dough to rise quicker
 They will also improve the volume & crumb
softness
 The enzymes used include amylase; both
alpha-amylase & beta-amylase (the two
naturally occurring enzymes in flour),
xylanases, proteinases & cellulases etc.

200. 200
 Vital Wheat Gluten or Gluten Flour
 Gluten is the protein present in flour, which is
responsible for the structure and stickiness of
the dough
 It is also a binder, making dough more elastic
and gives it a boost
 It also helps to compensate for the damage
done to the gluten in your bread dough due to
the bran’s jagged edges, which occur during
the milling process

201. 201
 Gluten is mainly found in the white flour
component of milled wheat, other cereals do
contain gluten but to any significant degree
 This is extracted from high protein wheat
 To obtain 'pure' gluten, flour is mixed with
water and the starch washed out, the remaining
gluten can be dried and bagged
 Gluten flour is added to doughs when the
gluten in the dough is not present in high
enough quality and quantity to produce a high
quality loaf of bread

202. 202
 Gluten needs to be added to ensure the dough
is strong enough to "hold up" any extra
components added to the recipe: whole-meal,
germ, kibbled wheat, corn etc.
 Gluten is also added to soft wheat flour to
improve its bread making quality
 Too much gluten flour will make bread tough
and rubbery
 Dried Fruit, Sprouts, Spices, Herbs, Cheeses,
etc. - Adds nutrition, crunch, flavor, variety,
fun, and adds to appearance

203. 203
 Straight dough method
 All of the ingredients are incorporated in one
long process of mixing & kneading rather than
in two short ones, as in the sponge & dough
process
 All the flour, water, yeast, sugar, salt, & one-
half the oil to be used (dissolve salt & yeast in
separate receptacles), are mixed in a low speed
mixer for10-20 minutes or until a stiff elastic
mass is achieved
 Salt addition is delayed until the dough begins
to clear the back of the mixer bowl

204. 204
 The resulting dough is set aside while
fermentation proceeds
 After about 2 hours in a 3 hours fermentation
process the dough is knocked back i.e.
manipulated to push out the gas that has been
evolved in order to even out the temperature
& give more thorough mixing
 After another hour’s rising the dough is
divided into loaf-sized portion & these are
roughly shaped
 The dough pieces are rested at about 27oC for
10-15 minutes & then moulded into the final
shape to tighten it sp that the gas is better
distributed & retained & placed in tins

205. 205
 The dough is let to rest again in the tins for the
final proof of 45-60 min at 43 oC & 80-85 %
relative humidity
 During final proof CO2 is evolved that inflates
the dough irreversibly
 The dough is then baked in the oven at
temperatures of 235 oC for 20-40 minutes,
depending upon the loaf size, some times
steam injected into the oven to produce a
glazed in the crust

206. 206
 The advantages of the method are:
 Lower requirements in the processing time,
labour, power & equipment
 Reduced fermentation losses because of its
generally shorter fermentation time compared
with the sponge & dough process
 It enhances bread flavor by subjecting all
dough ingredients to the same fermentation
treatment

207. 207
 The major limitation of this method is its
relative inflexibility with respect to
fermentation time & schedule adherence: the
dough must be made up when ready, with little
leeway in either direction

208. 208
 Sponge & dough method
 In this method major fermentation action
takes place in a preferment called the sponge
 In the sponge 50-70 % of the total dough flour
is subjected to the physical, chemical &
biological actions of fermenting yeast
 The sponge is combined with the rest of the
dough ingredients to receive its final physical
development during the dough mixing or
remix stage

209. 209
 For the second stage of the method the
fermented sponge is first mixed at slow speed
with the dry ingredients of the formula, except
salt,
 With the mixer at higher speed the liquid
ingredients are added followed by the addition
of shortening in 5-6 minutes
 Finally during the last two mintues salt is
added

210. 210
 The advantages of this method as compared to
the straight dough method are as follows:
 Slightly lower levels of yeast may be used i.e.
an average of 2.75% as compared with 3% in
the straight dough
 It yields bread with good flavor, optimum loaf
volume & superior grain & texture & softness
retention
 There is greater process flexibility in terms of
adaptability of minor schedule delays

211. 211
 The disadvantages of sponge & dough
method include :
 Greater equipment demand (e.g., two mixers
instead of one)
 Long processing time (about 7 hours from
sponge mixing to oven baking)
 Greater fermentation losses
 Higher labor costs

212. 212
 Mixing stages
 Mixing to the optimum degree of dough
development is vitally important for the
subsequent processing of the dough &
ultimately for the quality of the bread
 The main objective of the mixing is get a
homogenous mass of the ingredients in its
driest condition, with as high an absorption as
possible &, at the same time, of proper
consistency so it will machine well

213. 213
 The ultimate goal is thus to bring about an
optimum balance of the rheological properties
of the dough
 These properties include:
 Plasticity, which enables dough to retain the
shape imparted to it by rounding & moulding
 Viscous flow, or the property of the dough to
assume the shape of the pan or other container
in which it is placed
 Elasticity, or the ability of the dough to recover
partially from the deformations it undergoes
during moulding

214. 214
 Viscoelasticity, which combines viscous & elastic
properties & influences dough behavior from
makeup to baking
 Dough development during mixing is achieved in
four, fairly distinct stages
 The objective the initial stage is merely to ensure
the uniform blending of the dough ingredients
 The dough at this point is quite slack & rather wet
& sticky to the touch
 As mixing continues the dough enters pickup
stage
 During this stage gluten structure begins to form

215. 215
 During the third stage, referred as cleanup
stage, dough becomes drier & more elastic, &
forms into a more cohesive mass that slaps the
back wall of the mixer bowl with each
revolution of the mixer arms
 This stage is completed when the dough clears
away from the mixer bowl
 The development stage is fourth & the most
critical stage
 The dull surface appearance of the dough
transformed to smooth, satiny sheen

216. 216
 A fully developed dough exhibits a silky, dry
appearance & stretches into smooth, long sheet
 At this time the dough is ready for discharge
from the mixer to enter a short period of
recovery, or the “floor time” prior to makeup
 The doughs mixed beyond the development
stage begins to lose their elastic character &
become progressively soft, smooth & extensible

217. 217
 The dough begins to be pulled into long, cohesive
strands by the mixer bars
 This stage is “letdown” stage at which the doughs
begin to exhibit the signs of over-mixing
 Only very strong flours can be safely mixed to this
stage without a real risk of subsequent dough
failure during the makeup operations
 Carrying the mixing operation beyond this point
results in complete disintegration of the dough
 It become wet, excessively slack & stringy,
without any elastic properties & no longer be
salvaged for bread-making under practical
production conditions

218. 218
 Rapid dough processing
 The methods under this category involve the
use of an improver to assist in the dough
development & reduction of any individual
fermentation period, in bulk or as divided
pieces to less than 1 hour
 Three process included in this category
 Activated dough development
 No-time dough with spiral mixers
 Dutch green dough process

219. 219
Activated dough development
 It was developed in USA in 1960s
 The essential features of method are as follows:
 The addition of reducing agent, usually
cysteine
 The addition of oxidizing agents other than
added at the flour mill
 The addition of fat or an emulsifier
 Extra water I the dough to compensate for the
lack of natural softening
 Extra yeast to maintain normal proving times

220. 220
 At first potassium bromate was a common
component in the added improve, together
with ascorbic acid & L-cysteine hydrochloride
 Ban on potassium bromate & increased cost of
L-cysteine hydrochloride has resulted in the
demise of this method
 Since this method was chemically induced, so
the low speed mixers could be employed
 With the development of high speed mixers &
spiral type mixers, fewer chemicals can be
used at a time as consumer attitudes to
additives were changing

221. 221
 A short period of bulk fermentation before
dividing was beneficial for ADD product
quality
 Sponges could be used to change bread flavor
if required
 Final dough temperatures were in the region
of 25-27 oC

222. 222
No time doughs with spiral mixers
 Spiral mixers have a number of advantages for
no time dough making processes in smaller
bakeries or where fine cell structures are not
required in the baled product
 A short period of bulk fermentation, usually
20-30 minutes, can assist dough development
after mixing
 In these circumstances the control of final
dough temperature is important in order to
both control & optimize dough development

223. 223
 The additional gas generated during such bulk
resting periods requires greater divider weight
control & results in products with more open
cell structure
 Limited flavor development due to the short
fermentation time
 Spiral mixers can raise the temperature of the
dough above that expected from the
ingredients
 Final dough temperatures vary between 21-
27oC

224. 224
 Lower dough temperatures restrict yeast
activity which comes with the usually higher
levels of added yeast
 However lower temperature reduces chemical
& enzymic activity with a subsequent decrease
in overall development

225. 225
The Dutch green process
 The process is termed so as it was developed
in the Netherlands
 In this process the mixed dough passes
without delay to dividing, although
significant periods of resting are involved in
the total process
 The essential features of the process are:
 Mixing in a spiral type mixer or extra mixing
in a speeded up conventional low-speed
mixer
 The divided dough is rounded & given
resting

226. 226
 The dough is re-rounded & given a further
resting period before final moulding
 The basis of the name ‘green’ refers to the fact
that after the mixing the dough is considered
to be underdeveloped or ‘green’ in classic
bakery parlance
 Dough development continues in the resting
period after each rounding
 At first two or three resting times were used
two periods are in practice

227. 227
Role of improvers & ingredients in
rapid processing
 Although no-time doughs can be made
without additional ingredients, it is common
to use improvers to assist the dough
development in the absence of bulk
fermentation time
 Most of the improvers contain ascorbic acid,
enzyme active material & emulsifiers
 The degree of oxidation gained from the
ascorbic acid depends in part on the level used
& in part on the mixing machine & its ability to
occlude air during mixing

228. 228
 Mostly flours of stronger type with
protein content of 12% or more is used
 More water is required as no appreciable
softening of dough from fermentation
before divining
 The precise amount of water to be used is
influenced by the type of mixer used

229. 229
 Mechanical dough development
 The common elements are that there is no
fermentation period in bulk & dough
development is largely in the mixing machine
 The changes brought about by bulk
fermentation are achieved in the mixer through
the addition of improvers, extra water & a
significant planned level of mechanical energy
 The principle of mechanical dough
development was first successfully exploited in
the ‘Do-maker’ process in 1950s

230. 230
 The ‘Do-maker used a continuous mixer &
separate developer chamber
 Others processes exploiting the same principle
are Amflow process & Oakes special bread
process
 Chorleywood bread process (CBP) was
devised in 1961
 The essential features of the process are as
follows:
 Mixing & dough development in a single
operation lasting between 2-5 minutes at a
fixed energy input

231. 231
 Development of a dough by mechanical work
input at nominally 11 watt hours/kg in
approximately three minutes
 Addition of an oxidizing agent above that
added at flour mill
 The addition of a high melting point fat, an
emulsifying agent or a combination
 Addition of extra water, necessary to deal with
the retention of flour solids normally lost
during bulk fermentation & the absence of
dough softening which would have taken
place during this time

232. 232
 Addition of extra yeast which ferments less
rapidly during the early stages of final proof
 Reduction of flour protein to compensate for
the increase in specific volume compared with
bulk fermentation
 Use of a partial vacuum in the mixing chamber
to reduce the size of & control the crumb
structure
 The main difference between CBP & bulk
fermentation processes lies in the rapid
development of the dough in the mixer rather
than through a prolonged resting period

233. 233
 The aim the both processes is to modify the
protein structure
 In the dough to improve its ability to stretch &
retain gas from yeast fermentation in the
prover, achieved within 5 minutes of the
starting the mixing process in case of CBP
 The advantages gained by changing from bulk
fermentation to CBP include
 A reduction in processing time
 Space saving from elimination of the bowl of
dough at different stages of bulk fermentation

234. 234
 Improved process control & reduced wastages
in the event of plant breakdown
 More consistent product quality
 Financial savings from higher dough yield
through the addition & retention of flour
solids that are normally fermented away
 The disadvantages of the process include
 Faster working of the dough is required
because of the higher dough temperatures
used

235. 235
 The second mixing will be required for the
incorporation of fruit into fruited breads &
buns
 In some cases, a reduction bread crumb flavor
because of the shorter processing time
 The increase in the crumb flavor can be
achieved by the use of sponge or a flour brew