This document provides an overview of milk, including its source, composition, types, properties, nutritional value, contamination, and storage. It discusses that most milk comes from cows, though goat and sheep milk are also used. The composition of milk is described, including water, carbohydrates, fat, protein, vitamins, and minerals. Types of milk like whole, reduced fat, low fat, and skimmed are defined. The document also covers topics like flavor, contamination, microorganisms commonly found in milk, physical properties, nutritional benefits, consumer issues like lactose intolerance and milk allergies, and tips for proper storage.

1. MILK
Presented to:
Dr. Abid Zia
Represented by:
Mudasser Ahmad

2. Contents
1. Introduction
2. Source of milk
3. Milking and pasteurization
4. Composition of milk
5. Types of milk
6. Flavor
7. Contamination
8. Microorganisms of milk
9. Physical properties
10. Nutritive value
11. Consumers issues
12. Storage of milk
13. References

3. Introduction
•Milk is the food which exclusively
sustains us during the first few months of
life.
•The term milk is also used for white
color, non-animal beverages resembling
milk in color & texture such as soy milk,
rice milk, almond milk, & coconut milk.

4. Where milk comes from:
•Most milk comes from
cows, but you can also get it
from goats or sheep.
•Dairy cows are mainly
farmed for milk.

5. Milking
Cows are usually milked
morning and night by
dairymen.
Some farms use robot milking
machines, when the cows go to
milk themselves when they
want to.
Pasteurization
The milk is pasteurized to kill
any bacteria, by heating it to 71
C for 15 seconds.It is then put
into bottles or cartons and sold
in the shops.

6. Composition of Milk
1. Water: 87-88%
2. Carbohydrate: (approx. 5% )
3. Fat: 3-4% in whole milk;
4. Protein: (3-4%)
• Whey proteins (20% of milk protein)
• Casein (80% of milk protein)
5. Vitamins & Minerals
• Vitamins A, B6, B12, C, D, K, E,
thiamine,niacin,biotine riboflavin,folates, and
pantothenic acid
6. Minerals
• Ca & P approx. 1% of milk
• Other minerals present are chloride, magnesium,
potassium ,Sodium and sulfur.

7. Composition of milk
Buffalo milk : high fat content (7.44%)
Cow milk : low fat content ( 3.66%)

8. Types of milk
1. Standardized milk:
buffalo milk &skimmed milk (fat -5% )
2. Whole milk:
3.25% milk fat & 8.25% milk solids(50% of its calories
from fat)
3. Reduced-fat milk:
2% milk fat(35%of its calories)
4. Low-fat milk:
1%milk fat(23% of its calories)
5. Skimmed milk:
0.5%milk fat(5% of its calories from fat)
6. Dried milk:
in powdered form

9. 7. Evaporated milk:
homogenized milk with considerably reduced
water content.
8. Condensed milk:
simple evaporated milk to which sugar has
been added to thicken and sweeten it.It is
mainly used for making desserts and sweets

10. Flavor of Milk
• The flavor of milk is mild &
slightly sweet.
• Fresh milk contains acetone,
acetaldehyde, & methyl
ketones, that provide aroma.

11. Contamination of milk and milk products
• Milk is sterile at secretion in the udder but is
contaminated by bacteria even before it
leaves the udder.
• Further infection of the milk by
microorganisms can take place during milking,
handling, storage, and other preprocessing
activities.

12. Few types of micro organisms
found in milk.
Streptococcus lactic
Bacillus subtilis
Coliform bacteria
Achromobacter

13. Physical Properties:
Acidity: fresh milk pH is 6.5-6.7 at
25°C
Viscosity: depends on the amount of
fat, size of fat globules & extent of
clustering of globules.
Homogenisation & ageing increase the
viscosity
Freezing point:-0.55°C addition of
1% of water to milk ↓ FP by
0.0055°C.
Boiling point: 100.2°C

14. Nutritive value:
•Good quality protein
•Easily digestible fat containing 2.1% linoleic acid,
0.5% linolenic acid & 0.14% Arachidonic acid.
•Only substance that contain lactose suitable for
Synthesis of myelin sheath(galactose) and Favors the
growth of lacto bacillus in intestine & decrease the pH
thus favoring Ca absorption.
•Also increases the permeability of Small Intestine for
Ca+2.
•Poor source of iron & vit C.
•Not a good source of niacin but excellent source of
tryptophan.
•Major source of Calcium & riboflavin.

16. CONSUMER ISSUES
Lactose intolerance
• due to a natural intolerance to lactose (sugar in milk)
• Normally lactose is broken down, or digested, by an enzyme called lactase. As we get
older, the amount of the enzyme in our body decreases. Lactase declines rapidly after
weaning.
• Body’s inability to digest Lactose results in symptoms such as bloating and diarrhoea.
• People with lactose intolerance can sometimes take small amounts of milk without
being too ill and can usually drink fermented milk products, Low lactose milks have
also been developed. Milk products, such as cheese and ice-cream, should not in
themselves present problems to lactose intolerant consumers but the practice of
adding back milk solids reintroduces lactose.
• Some lactose intolerance is not due to low lactase levels but to other things such as
Crohn’s disease, Coeliac’s disease or acute gastroenteritis.
Milk Allergy
• allergy to the protein in milk, causing an immune-system response in the body.
• Allergy sufferers needs to totally eliminate milk, dairy products & any foods containing
milk ingredients.
• dairy alternatives, such as milk from soya and cereals, are available to allergy
sufferers.

17. Storage tips
A. Pick up as one of the last items in store
B. Refrigerate as soon as possible
C. Use milk in order of purchase from
individual refrigerators at home
(Put freshest milk in the back and use the oldest
first)
D. Refrigerate after opened.

18. Refrerences
• Srilaksmi.B, Food Science, Third
Edition, 2003, New Age
International Publisher, New Delhi.
• Vaclavik,V.A., Christian,E.W.,
Essentials of Food Science, Third
Edition, Springer.
• Journal of food science &
technology
• www.wikipedia.com
• http://www.ifst.org/learninghome/