INTRODUCTION:when we reach for the sugar bowl, we are reaching for sucrose. And,
whether you know it or not, we’re opting for one of the purest foods found
on the kitchen pantry shelf and in prepared food products. For thousands of
years sugar has been an important food ingredient that provides a balanced
sweet taste, safety as a preservative and provides functional properties
essential in a multitude of foods. Sugar (sucrose) is a natural carbohydrate,
found in fruits and vegetables.
All green plants manufacture sugar through photosynthesis , the process by
which plants generate energy and food reserves from sunlight .
Just as sugar plays a vital role in the growth
and life cycle of plants, it is an important ingredient in our food supply. While
all fruits and vegetables produce sugar, the sugar cane and sugar beet plants
contain the most accessible stores of sucrose.
RAW MATERIAL :-
In sugar industry processes sugar cane and sugar beet are used to
manufacture edible sugar. More than 60% of the world’s sugar production is
from sugar cane; the balance is from sugar beet. Sugar manufacturing is a
highly seasonal industry, with season lengths of about 6 to 18 weeks for
beets and 20 to 32 weeks for sugar cane. Approximately 10% of the sugar
cane can be processed to commercial sugar, using approximately 20 cubic
meters of water per metric ton of cane processed. Sugar cane contains 70%
water; 14% fiber; 13.3% saccharose (about 10 to 15% sucrose), and 2.7%
There are two main raw materials used for
production of sugar ,
Cane sugar :
Sugar cane is a tropical grass
that grows 10-20 feet high.
Four U.S. states produce sugar
cane: produces his own sugar
with more and more production
of sugar cane .
A stalk of the sugar cane plant
contains 12-14% sucrose.
The process of separating sugar
from the sugar cane plant is
accomplished in two steps: 1st at
sugar mills and 2nd at sugar
Composition of Sugar Cane :
10 – 15 %
10 – 15 %
0.5 - 2 %
2. Beet Sugar :-
flourish in temperate climates
where the soil is rich and the
growing season is about five
months long. Farms can be
found in California, Colorado,
Idaho, Michigan, Minnesota,
Montana, Nebraska, North
Dakota, Oregon, and
Wyoming. Sugar beets
contain 16-18% sucrose and
are processed at factories
near the farms. Since sugars
beets are grown and
factories generally operate for
a campaign (a period of time)
of four to seven months.
During these campaigns,
facilities operate around-theclock, seven days a week.
Types of Sugar :-
There are several types of sugar , from which some are mentioned below ,
Granulated Sugar :-
Granulated sugar is a general type of sugar , which is used generally today .
Granulated sugar contain less quantity of molasses means a syrup which is
responsible for the sugar sweet.
Brown sugar :-
Brown sugar is sugar crystals in a specially prepared molasses syrup with
controlled natural flavor and color components. A number of sugar refiners
make brown sugar by preparing and boiling a special syrup containing these
components until brown sugar crystals form. Others produce brown sugar by
blending a special molasses syrup with white sugar crystals.
Manufacturing of Sugar :-
For many people, the term “refined” has lost its original meaning “to purify”
and now carries a negative connotation. With sugar the refining process
simply removes all impurities and the surrounding plant matter leaving only
the pure sucrose. To further your understanding of sugar (sucrose) and its
path from the field to the table, we provide the following plant to pantry
Sugar cane is a tropical grass that grows 10-20 feet high. Four U.S. states
produce sugar cane: Florida, Hawaii, Louisiana and Texas. A stalk of the
sugar cane plant contains 12-14% sucrose.
The process of separating sugar from the sugar cane plant is accomplished in
few steps: at sugar mills and at sugar refineries ,
Washing of cane sugar
Washing of cane sugar :-
Cane sugar obtained from field is first washed properly to remove all dust ,
insects and all other physical impurities .
This is done by adding milk of lime and carbondioxide. The carbon dioxide
bubbles through the mixture forming calcium carbonate, a chalk like crystal
which attracts the non-sugar plant materials like wax, fats, and gums from
the juice. In a clarifier, the calcium carbonate and the other materials fall out
of the sucrose solution and settle to the bottom.
by removing water from the clarified juice in multiple stages under vacuum.
This allows the juice to boil at lower temperatures to protect the sugar from
caramelization. The juice becomes a clear, rich brown syrup during this step.
CRYSTALIZATION:-by evaporating the last portion of water under
very tight controls in a vacuum pan. Seed grain (pulverized sugar) is fed into
the pan as the water evaporates and crystals begin to form. The mixture
leaves the vacuum pan as a thick crystal mass and is sent to a centrifuge, a
large perforated basket spinning very rapidly much like a washing machine in
the spin cycle, where it is spun and dried, yielding golden raw sugar.
In its pure form this sugar is crystalline in nature. Sucrose content in fully
mature cane ranges.
from 12-15%. Under conditions of low pH or under influence of certain
enzymes like inverts , sucrose is hydrolyzed into two monosaccharide viz.
glucose and laevulose in equimolecular proportions according to equation :
This reaction is commonly known as inversion and the resulting solution
as invert sugar.
Following are some physical and chemical properties of sucrose which is
basically a disaccharide:
Physical properties :
(i) Molecular weight 342.3
(ii) Density of 26% solution at 20°C 1.108175
(iii) Sucrose melting point is 188°C but it decomposes on melting.
(iv) Sucrose is soluble in water and ethanol and the saturated solution in water at 20°C
contains 67.09% sucrose by weight & in ethanol at 20°C, 0.9% by weight.
(i) When heated to 200°C the sucrose loses water forming brown coloured
compound known as caramel.
(ii) Sucrose on treatment with concentrated nitric acid is transformed into oxalic acid.
(iii) On treatment with oxygen the sucrose is converted into dicorboxylic or acid ,
(iv) When concentrated sulphuric acid is added to it sucrose is
charred with evolution of C02 and SO2 .
(v) Sucrose reacts with hydroxides of calcium, barium and
strontium to form corresponding sucrates .
APPLICATIONS OF SUGAR :-
Sugar is an important source of
carbohydrate, contains no fat or cholesterol, and 15 calories are contained by
a teaspoon of it .
Sugar is listed by the Food and Drug Administration
(FDA) as GRAS (Generally Recognized As Safe) .
Sugar plays an important part in making good foods taste even better and
has many functional attributes in food preparation. In addition to its role as a
flavor enhancer, sugar can act as a preservative, a bulking agent, a
balancing agent, and a fermentation aid. It is sugar that helps bread to rise,
heightens flavor and preserves fruit in jams and jellies, provides smooth
texture to candies and sauces, and balances the tart flavors of other
ingredients in many main dish recipes.