Chemical additives are used as non-preservatives to improve flavor, taste, nutrition, and the functional properties of foods. Flavors can be extracted from natural materials or synthesized. Flavor enhancers accentuate natural flavors without adding their own. Sugar, salt, and spices are used to improve taste. Nutrients like vitamins and minerals are added to fortify foods. Additives like emulsifiers, stabilizers, thickeners, and leavening agents are used to improve texture and structure. Preservatives like anti-ripening agents, sprout inhibitors, antimicrobials and antioxidants are used to increase shelf life by controlling ripening, sprouting, microbes and oxidation.

1. Chemical
additives as non-
preservatives
• Improve flavor
• Improve taste
• Improve nutrition
• Improve functional
properties of food

2. Improve flavor
Natural flavoring substances include spices,
herbs, essential oils and plant extracts.
Currently there are 12000 different flavoring
materials used in foods.
Number of flavoring compounds are extracted
from natural raw materials while large numbers
are synthesized.
Extracted flavors from plant materials in the
form of essential oils and oleoresins used as
flavoring agents.

3.  Flavors derived from orange and lime peels are
common ingredients in orange and lime-based
products.
 Synthetic flavors:
 Commonly added to food material
 Available in powder or liquid forms or as
encapsulated dry flavors
Compounds Flavors
Ethyl butyrate Pineapple flavor
Methyl anthranilate Grape flavor
Amyl acetate Banana flavor
Benzaldehyde Almond flavor

4. Flavor enhancers
 Additionally some substances called flavor enhancers
are added to accentuate the original flavor of the
foodstuff.
 These may not have a flavor of their own but are
efficient in bringing out the natural flavors of food to
which they are added.
 Monosodium glutamate is a common flavor
improver used in meats, gravies, sauce and food rich
in proteins.
 Its excessive use can results in toxicity- a burning
sensation in the back of neck.

5. Improve taste
 The basic quality of foodstuff meant for human
consumption is that in addition to its appearance, it
should have a good taste.
 All foods have natural taste of their own.
 Several additives are used to improve the taste of
foods i.e.
 Sugar
 Salt
 Spices
 Synthetic low caloric sweeteners
 Accidulants

6. Improve nutrition
 Generally natural foods lack a few nutrients or may
lose some during processing.
 Foodstuff is fortify with suitable nutrients.
 Addition of vitamin A and D and iron to infant milk
recipes.
 B vitamins, iron and calcium to cereal products.
 Iodine to common salt
 Vitamin C to fruit products
 Vitamin A to butter and margarine

7. Improve functional properties
of foods
 Fresh and processed foods have characteristics
textural properties.
 It may be necessary to add substances that will favor
the attainment of desired characteristics.
 Texture of potatoes, peas and tomatoes soften on
canning so addition of calcium chloride or calcium
phosphate provides firmness to the product.
 Similarly in salad dressings and mayonnaise
production, emulsifiers are added to form
homogenous mixture of oil and water.

8.  Emulsifiers such as monoglycerides, diglycerides
and phospholipids help in the formation of the
oil/water emulsion, which is stable.
 Emulsifiers are also important in the baking
industry where they are used to improve the
volume, uniformity and firmness of grain in bread.
 They also favor the distribution of fat in the batter
and give stability to structure in baked goods.

9.  Stabilizers and thickeners are also important in
several manufactured products such as cake
toppings, chocolate milk drinks, jellies, puddings,
salad dressings, gravies and others.
 Prevent separation of ingredients.
 Calcium gluconate and calcium chloride are
permitted stabilizers in jams, jellies, pickled
cucumbers as well as canned peas, tomatoes.
 In evaporated milks, sweetened condensed milks,
milk powders and cream, mono-calcium
phosphate and tri-potassium citrate are used.

10.  In ice creams stabilizers increases viscosity and
prevent formation of large ice crystals.
 Vegetable gums ( gum Arabic, pectin & gelatin)
and cellulose compounds ( methyl cellulose &
carboxymethyl cellulose) are also used as
stabilizers and thickeners in numerous products.
 Leavening agents are useful in production of bread,
cakes, biscuits, wafers, muffins and many other
baked goods.
 Give desired textural characteristics to the product
 i.e. sodium bicarbonate and baking powders,
which contain sodium bicarbonate, an acid, salt and
starch.

11.  Moisturizing agents, commonly known as
humectants are employed to retain moisture in
products like shredded coconut.
 Anticaking agents are added to sugar, salt, garlic
and onion powders, powdered sugar and milk
powders to prevent caking.
 Clarifying agents help to improve the filterability,
appearance as well as the quality of product to which
they are added.
 Chemical additives are used as glazing agents
(prevent water loss, curing agents (to remove
moisture from foods) and foaming agents.
 State food laws regulate the limit as to the use of
these substances.

12. Chemical Additives as
preservatives
 In addition to use of chemicals for various non-
preservative purposes, some are employed to
increase the shelf life of the food.
 Among these are:
 Anti-ripening agents
 Sprout inhibitors
 Anti-microbial agents
 Anti-oxidants

13. Chemical
Additives as
preservatives
• Anti-ripening
agents
• Sprout inhibitors
• Anti-microbial
agents
• Anti-oxidants

14. Anti-ripening agents
 Fruits continue their normal physiology even after
they are detached from the tree and ripen after
harvesting.
 Sometimes during cold storage of such
commodities, it is essential to control the ripening
process.
 Purafil & 2,4,5- trichlorophenoxy acetic acid
help to retard the ripening process in fruits.

15. Sprout Inhibitors
 Onions, carrots, potatoes that grow beneath the
soil surfaces sprout during storage.
 Sprouting is a process by which plants produces
new leaves or buds or other newly developed parts
experience further growth.
 Potatoes especially vulnerable when the storage
temperature is moderate 25 or 30 º C and relative
humidity is 50-80%.
 Methyl esters of naphthalene acetic acid ,
maleic hydride are employed.

16. Antioxidants
 Antioxidants are substances that prevent the
reaction of various food constituents with oxygen
thereby avoiding deterioration caused by simple
oxidative chemical reactions.
 Oxidative changes occur in unsaturated food
components that include fats and oils, carotenoids
and porphyrin-like compounds (e.g. chlorophyll,
haemoglobin).
 Fats and oils are particularly vulnerable to oxidation
resulting in off-odor development and deterioration
in commodity.

17.  Antioxidants e.g.
 α-tocopherol
 Butylated hydroxytoluene (BHT)
 Butylated hydroxyanisole (BHA)
 Isopropyl citrate mixture
 Propyl gallate
o Used to offset oxidative rancidity in fats and oils, in
fried potato chips, salted nuts, crackers, breakfast
cereals, fat containing dehydrated foods, or other
fatty foods.
o These products remain fresh on the shelf for much
longer period in the presence of the anti-oxidants
than in their absence.

18. Additives used as
anti-oxidants
Foods
Alpha tocopherol
• Mayonnaise
• Canned baby food
• Edible fats and oils
Ascorbic acid
• Canned mangoes
• Mango chutney
• Jams , jellies
• Canned peaches
BHA
• Mayonnaise
• Margarine
• Butter oil
BHT • Edible fats and oils

19.  The process of rancidity in fats and oils is
stimulated by the presence of metallic ions such as
copper and iron.
 These come in contact with lipids during
processing or storage in iron or copper
containers or may be part of the food system.
 Importance to prevent contact of these metal
catalyst with the unsaturated fats and thus
hinder their catalytic action.
 chemical compounds generally referred to as
sequestering or chelating agents are employed
to inactivate metals.

20. Sequestrants or sequestering
agents
 Compounds that are capable of inactivating a
metallic ion by forming a complex (usually water
soluble) in which covalent bonds holds the metal in the
complex.
Chelating agents
 Compounds containing two or more donor groups that
can combine with a metal to form one or more ring
structures.
 Examples are ethylendiamine tetra-acetic acid
(EDTA), polyphosphates and citric acid.

21. Anti-microbial agents
 Micro-organisms are present on the surface of fresh
food commodities; these also find their way into
processed foods.
 If these are not inhibited, they will grow and cause
spoilage.
 Fruits are treated with fungicidal solutions to
prevent fungal growth on their surface.
 Citrus fruits are dipped into sodium salt solutions.

22. Anti-microbial agents in food
preservation
 Salt
 Sugar
 Smoke
 Vinegar
 Organic acids
 Parabens
 Nitrates
 Fatty acids
 Hydrogen peroxides
 Phosphates

23.  Some naturally occurring compounds produced by
lactic acid bacteria or those present in spices and
herbs are effective against microbes.
 Fumigants also help to control microbial growth on
spices, nuts and dried fruits.
 Production of pan bread and cakes, sodium and
calcium salts are employed as mould inhibitors.
 Fruits and vegetables may be washed in water
containing germicidal substances like chlorine.
 Potassium and sodium metabisulphite are used in
the preservation of syrups, juices and squashes.

24. Choice of anti-microbial agents
Depends upon several factors:
 Properties
 Safety
 Cost of compound
 Properties of food
 Possible effect of chemical on food quality
 Type and level of micro-organism present
 Post-processing and storage conditions
 Food laws of the country