1. 3.1 BIOCHEMISTRY OF
FOOD SPOILAGE
(3.1.1 Factors causing food
spoilage during food ripening,
vegetable maturation and their
control)
PRESENTED BY
JYOTI DEVENDRA ADALA
2. He may live without books- what is
knowledge but grieving.
He may live without hope- what is hope but
deceiving.
He may live without love- what is passion but
pining.
But show me the man who can live without
EATING!
3. FOOD SPOILAGE
Food spoilage is the process in
which food deteriorates to the point in
which it is not edible to humans or its quality
of edibility becomes reduced.
As a result abnormal colors, off flavors or
other alterations develops.
5. PHYSICAL
SPOILAGE
Caused by the inappropriate transport, handling
and storage.
Food spoilage can be caused by physical
factors, such as temperature, moisture and
pressure acting upon the foods.
6. ACTION OF MICROORGANISMS
Bacteria and fungi are the
principal types
of microorganisms that cause
food spoilage when the
conditions for their growth are
appropriate.
The typical microorganisms
that cause food spoilage
are bacteria (e.g.,
Lactobacillus), yeasts (e.g.,
Saccharomyces).
7. ACTION OF MACROORGANISMS
Food are mechanically
damaged by insects,
rodents, worms, etc.
For example: The hole on
the surface of tomatoes,
cucumber, brinjal indicate
that they are harboring
larvae of insects.
8. ENZYMATIC SPOILAGE
Enzymes are large protein molecules that act as biological
catalysts, accelerating chemical reactions without being
consumed.
After the harvesting of fruits, enzymes remain active within the
cells. They continue to catalyse the biochemical processes of
ripening and may eventually lead to rotting.
E.g.: banana.
9. NON ENZYMATIC SPOILAGE
The Maillard Reaction (also known as browning) is a type of non-
enzymatic browning which involves the reaction of simple sugars
(carbonyl groups) and amino acids (free amino groups).
Non enzymatic browning causes spoilage during the storage of dry
milk, dry whole eggs and breakfast cereals.
12. FOOD PRESERVATION METHODS
1) FREEZING AND CHILLING
2) THERMAL PROCESSING
3) FOOD IRRADIATION
4) DEHYDRATION
5) NATURAL AND CHEMICAL PRESERVATIVES
13. FREEZING AND CHILLING
CHILLING
The life of many foods may be
increased by storage at
temperatures below 4° C.
Freezing
The freezing of food involves
lowering its temperature below
0° C resulting in the gradual
conversion of water present in
the food into ice.
14. THERMAL PROCESSING
Heat is effective in destroying vegetative cells.
However excessive bring about undesirable
changes.
1) Canning
2) Blanching
3) Pasteurization
4) Sterilization
15. FOOD IRRADIATION
Food irradiation involves the use of either
high-speed electron beams or high-energy
radiation (e.g., X rays and gamma rays).
Radiation destroys microorganisms by
changing the structure of cell membranes.
16. DEHYDRATION
-The water content of foods can be
controlled by removing water
through dehydration. Loss
of moisture content produced by
drying results in increased
concentration of nutrients in the
remaining food mass.
-Reduces the bulk weight.
17. NATURAL AND CHEMICAL
PRESERVATIVES
Food preservatives are substances which under
certain conditions delay the growth of
microorganisms without necessarily destroying
them.
NATURAL PRESERVATIVE- salt, sugar, vitamins C.
CHEMICAL PRESERVATIVE – benzoic acid,
butylated hydroxyanisole (BHA).
