Here are the key points discussed in the document: - Food provides nutrients like carbohydrates, proteins, fats, vitamins and minerals that are essential for energy, growth, tissue repair, regulating body processes and protecting against disease. - Food comes from both plant sources like fruits, vegetables and grains, as well as animal sources like meat, dairy and eggs. - Microorganisms naturally exist in food and can either positively impact food through processes like fermentation, or negatively impact food through spoilage and causing foodborne illness. - Specific microorganisms are used in controlled fermentation processes to produce foods like cheese, yogurt and bread. Enzymes from microbes are also used to produce some foods and food

1. Food Microbiology
Dr. M. S. Rajalakshmi
Assistant Professor
Department of Microbiology
Rathinam College of Arts and Science
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2. Synopsis
• Introduction
• Role of Food
• Essential Nutrients
• Desirable and Un Desirable food
• Pop Quiz/Discussion
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FOOD MICROBIOLOGY

3. WHAT IS FOOD ?
• Food is defined as any substance that people and animals eat to
survive.
• Animal and plant are the main sources of food.
• It is eaten because they provide energy and nutrition and keeps
people and animals healthy.
• Fruits, vegetables, grains, seeds, herbs, are the obtained from
the plant sources.
• While dairy products, seafood, meat, and eggs are obtained
from the animal sources.
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4. DEFINITION OF FOOD
• Food can be defined as anything edible that can be solid, semisolid
or liquid which when swallowed, digested and assimilated in the
body, proves useful to it.
• These substances not only keep the person alive, but also provide
energy used for growth and development, regulate the body
processes and protect the body from diseases.
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5. FUNCTION/IMPORTANCE OF FOOD
• 1 The Physiological functions
To provide energy
To repair body tissues
To build new cells and tissues
To regulate body processes
To protect against diseases.
• 2 The social functions of food
• 3 The psychological functions of food.
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6. The Physiological functions
To provide energy
• Body needs fuel for voluntary and involuntary activities.
• Carbohydrate and fat rich foods are main sources
• Carbohydrate are starch, sugars and cellulose. Fat sources
are vanaspati, butter, ghee, nuts and oil seeds. - 1 gram of
carbohydrate yields 4 kilocalories, 1 gram of fat yields 9
kilocalories, 1 gram of protein yields 4 kilocalories.
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7. To build cells and tissues
• Proteins, water and minerals build cells
muscles and blood. Protein sources are
cereals and pulses.
• Animal protein comes from milk products
eggs, fish and meat. Minerals are found in
egg, meat, fish, green leafy vegetables etc.
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8. To repair cells and tissues
• Body tissues are continually broken
down and replaced by new ones.
Proteins, minerals and water is
required to replace them.
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9. To regulate body processes
• Essential fatty acids present in certain
fats, proteins, minerals, vitamins and
water all perform certain regulatory
functions – coagulation of blood,
maintenance of body temperature,
activation of enzymes etc.
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10. To protect the body from diseases
• Vitamins and minerals protect body from injury and
diseases.
• They help in regulating growth, muscular co-
ordination, eye sight, digestion and other body
processes.
• These are present in green leafy vegetables, other
vegetables, milk, meat, liver and eggs etc.
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11. FOOD MICROBIOLOGY
• Food Supply consist of basically plants and
animals or products derived from them.
• It is understandable that our food supply
can contain microorganism in interaction
with food.
• These microorganisms use food supply as a
source of nutrients for their own growth.
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12. FOOD MICROBIOLOGY
• These will cause two possibilities.
• Either – Results in deterioration of
food (Spoil)
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13. FOOD MICROBIOLOGY
• OR These Interactions between Microorganisms and food give
beneficial to human
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14. FOOD MICROBIOLOGY
• Example : Two species of Penicillium fungus are named after cheeses.
• One of them is P. roqueforti, gives blue cheeses like Roquefort.
• Cheese makers add P. roqueforti to the milk, so it’s present throughout the cheese. Blue
mold grows and produce the beautiful blue veins that characterize these cheese
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15. HOW MICROORGANISM CAN CAUSE
DETORIORATION OF FOOD?
• When they utilize the nutrients of the food, it involved changes in the
food compounds.
• Synthesis of a new compound that cause spoiling of food.
or
• Produced enzymatic Changes and contributing of flavors by means of
breakdown of product
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16. WHAT ARE THE IMPORTANCE OF
MICRORGANISMS IN FOOD?
• GOOD (Desirable)
• Food Bioprocessing
• Food Bio preservation
• Probiotics
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• BAD (Undesirable)
• Foodborne Diseases
• Food Spoilage

17. GOOD (Desirable)
• Food Bioprocessing
• Means – Foods produced by biological process
• In this process food grade microorganisms are used to produced different
types of fermented food using raw material from animal and plant sources
(Starter Culture).
• Microbial Enzymes also being used to produce food and food additives.
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18. GOOD (Desirable)
• Starter Culture
• A concentrated preparation of
live cells that is added to raw
material to initiate
fermentation rapidly.
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19. GOOD (Desirable)
• Food Bio preservation
• Is a food biological preservatives by using antimicrobial
metabolites ( taken from certain microorganisms in order
to control pathogenic and spoilage microorganism in food)
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20. GOOD (Desirable)
• Probiotics
• Is a concentrated supplement f beneficial live cell of bacterial culture
taken from orally intended to improve your health by promoting our
body’s natural immunity and improving digestion system.
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21. Bad (Undesirable)
Foodborne Diseases
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Food Spoilages

22. 21-07-2022 22
• Annotate on Food and importance.
• A balanced food is important for good health? True of False
• Fibrous food is essential for maintaining __________.
• Role of NaCl in food is _________.
• Antimicrobial metabolites acts a ______ in terms of food.
Discussion