2. Definition of milk_ composition of milk of different livestock species.pdf

Material

1. ✓Definition of milk and composition
✓Definitions
✓ Composition of different livestock species
Outline

2. Learning Outcomes
• Students will be able :
a)To understand the concept and terminology of milk.
b)To acquaint with the composition of different livestock species.

3. Definition: Milk is defined as a whole, fresh and clean lacteal secretion
obtained by the complete milking of one or more healthy milch animals
excluding that obtained within 15 days before and 5 days after calving is
called as milk. Or
Milk may be defined as a mammary
secretion of mammary gland of the
mammals.


MILK
https://www.thestatesman.com/wp-content/uploads/2018/08/milk.jpg

4. •It is the secretion of mammary glands in human and animals after labour.
•It is the only food for newborn for a long period till weaning time.
•Before birth the fetus receives its nutrition through the placenta.
•Milk secretion is stimulated by Prolactin.
•Milk flow is decreased by Estrogen and Progesterone, while increased by
Thyroxin.
•Initiation of lactation may result from sudden removal of the placenta
and other factors.
•Oxytocin (posterior pituitary hormone) responsible for milk ejection.
MILK

5. Composition of Milk of Different Livestock Species
Cowmilk
Water-87%
Fat –3-4%
Protein –3.5%
Lactose -5%
Minerals-0.8%
http://knowthecow.org/images/cow-feeding.jpg
https://toppng.com/uploads/preview/lass-of-milk-transparent-
background-png-milk-in-glass-11562957302a9wnzjoton.png
Yakmilk
Water-83%
Fat –5.5-9%
Protein –4-5.9%
Solid Content – 18%
https://cdn.britannica.com/40/188540-050-9AC748DE/Yak-Himalayas-Nepal.jpg
https://toppng.com/uploads/preview/lass-of-milk-transparent-
background-png-milk-in-glass-11562957302a9wnzjoton.png

6. Composition of Milk of Different Livestock Species
https://toppng.com/uploads/preview/lass-of-milk-transparent-
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https://toppng.com/uploads/preview/lass-of-milk-transparent-
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Buffalomilk
water –82%
minerals –0.8%
protein –4.5%
lactose–4.8%
fat –7to9%
very high fatcontent
Camelmilk
water –86.5%
Fat - 4%
protein –3.6%
lactose–5%
Mineral – 0.4%
https://4.imimg.com/data4/NR/LJ/MY-3775073/indian-buffalo-
500x500.png
https://lh3.googleusercontent.com/proxy/vt4G1TQ3CqmauXQCH7aTrtdWLa_DnOYWSGx8QJAy
eaGqSghvojbbNkYcBr5QIvzE0dvkg1QKd96FaloFydI-dM2K192n-0YjTcVJ6ZA1E7AU4hEVB6UlRHi3

7. Composition of Milk of Different Livestock Species
https://toppng.com/uploads/preview/lass-of-milk-transparent-
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https://toppng.com/uploads/preview/lass-of-milk-transparent-
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Goat Milk
❑ Water – 87%
❑ Fat – 4%
❑ Protein – 3.6%
❑ Lactose – 4.5%
❑ Minerals – 0.9%
Sheep Milk
❑ Water – 80%
❑ Fat – 8%
❑ Protein – 5%
❑ Lactose – 4.8%
❑ Minerals – 0.9%
https://www.breedslist.com/wp-content/uploads/2016/08/Bannur-
Sheep-Pictures.jpg
http://3.bp.blogspot.com/-
wLfU6rCtYIc/Us6VrDY48YI/AAAAAAAACpU/d_eASwT_zD0/s1600/konkan+kanyall.jpg

8. Composition of Milk of Different Livestock Species
https://toppng.com/uploads/preview/lass-of-milk-transparent-
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https://toppng.com/uploads/preview/lass-of-milk-transparent-
background-png-milk-in-glass-11562957302a9wnzjoton.png
Mare Milk
❑ Water – 89.10%
❑ Fat – 1.60%
❑ Protein – 2.70%
❑ Lactose – 6.10%
❑ Minerals – 0.50%
Reindeer Milk
❑ Water – 68.70%
❑ Fat – 17.10%
❑ Protein – 10.40%
❑ Lactose – 2.30%
❑ Minerals – 1.50%
https://media.npr.org/assets/img/2018/07/10/dsc07545-1--
3e78c902c20ebbf203b86800ebf0af3a442656dc.jpg
https://static-
cdn.sr.se/images/2054/2415161_520_292.jpg?preset=1024x576

9. Average Chemical Composition of Cow & Buffalo Milk
Table No.1. Average Chemical Composition of cow milk of an Indian breed
ConstituentsWater Fat Protein Lactose Ash
Per cent 86.90 4.00 3.50 4.90 0.70
Table No.2. Average Chemical Composition of buffalo milk of an Indian breed
ConstituentsWater Fat Protein Lactose Ash
Per cent 83.63 6.56 3.88 5.23 0.70

10. MILK
Water Totalsolids
Fat(lipid)
Truefat
Associated
substances
Phospholipids Cholesterol Carotene
Vitamins
A,D,E,K
Solid non
fat (SNF)
Lactose
Nitrogenous
substances
Protein Non-protein
Casein Lactalbumin lactoglobulin
Proteo-
peptone
Mineralmatter(Ca,
Mg, Na,etc.) Fe, Cu
Trace elements
Other
constituents
pigments
Dissolvegases
Vitamins
B Complx. C
Enzymes
Composition of Milk

11. i) Water – Constitutes the media in which the other milk constituents are either dissolved or
suspended.
Most of it is ‘free’ and only a very small portion is in the bound form, being firmly bond by
milk proteins, phospholipids etc.
ii) Milk fat (Lipids) – The bulk of the fat in the milk exist in the form of small globules, which average
approximately 2 to 5 microns in size (0.1 to 22 microns).
This is in oil in water type emulsion. Chemically milk fat is composed of a number of glycerides-
esters of fatty acids.
The surface layer of these fat globule is coated with an absorbed layer of material commonly
known as the fat globule membrane.
This membrane contains phospholipids and proteins in the form of a complex, and stabilizes the
emulsion.
In other words, the membrane prevents the fat globules to grow together keeps separated
from one another.
MAJOR CONSTITUENTS OF MILK

13. Major Fatty acids in milk
Long chain
•C14-Myristic 11
•C16-Palmitic 26
•C18-Stearic 10
•C181-Oleic 20
Short chain
•C4-Butyric
•C6-Caproic
•C8-Caprylic
•C10-Capric

14. •iii) Milk proteins – Proteins are among the most complex of organic substances.
• They are vital for living organisms as they constitutes an indispensable part of the
individual body cell.
• Proteins are composed of large number of amino-acids.
• The proteins of milk consist mainly of casein, beta lactoglobulin, alpha lactalbumin etc.
• Casein exist only in milk and is found in the form of a calcium caseinate –phosphate
complex.
• It is present in the colloidal state (range of 1 nm to 1 micrometer).
• It forms more than 80 percent of the total protein in milk.
• It may precipitated by acid, rennet, alcohol, heat and concentration.
• Casein itself is composed of alpha, beta and gamma fractions.
• Beta lactoglobulins and alpha lactoalbumin are also known as whey or serum proteins.
• They are also present in colloidal state and easily coagulable by heat.

17. •iv) Milk Sugar (Lactose) – This exist only in milk. It is in true solution in
the milk serum (molecules size below 1 nm).
• On crystallization from water, it forms hard gritty crystals.
• It is one sixth as sweat as sucrose.
• Lactose is responsible, under certain conditions, for the defect known
as ‘sandiness’ in ice-cream and sweetened condensed milk. Chemically,
Lactose is composed of one mole of glucose and galactose.
•(Prevention:Sandy texture can be prevented/reduced byrapid
hardening of the ice cream, by maintaining low storage room
temperature and preventing temperature fluctuations.)

18. •v) Mineral matter or ash-
•present in small quantities,
•exert considerable influence on the physico-chemical properties and
nutritive value of milk.
•include potassium, sodium, magnesium, calcium, phosphorus, citrate,
chloride, sulphate and bicarbonate. .
• The trace elements include all other minerals and salt compound.
• The mineral salts of milk are usually determined after ashing.

20. B. Minor Milk Constituents:
a) Phospholipids:
• In Milk, there are three types of phospholipids, viz, lecithin, cephalin and
sphingomylin.
• Lecithin, which forms an important constituents of the fat globule membrane,
contributes to the richness of flavours of milk and other dairy products.
• It is highly sensitive to oxidative changes, giving rise to oxidized/metallic
flavours. Phospholipids are excellent emulsifying agents, and no doubt serve to
stabilize the milk fat emulsion.
b) Cholesterol: This appears to be present in true solution in the fat, as part of the fat globule
membrane complex and in complex formation with protein in the non-fat portion of milk.

21. c) Pigments : These are (i) fat soluble, such as carotene and xanthophyll and (ii) water
soluble, such as riboflavin.
Carotene is the colouring matter of all green leaves, where it is masked by
chlorophyll.
Carotene ( Actually Reddish brown colour) is fat soluble and responsible for the yellow colour
of milk, cream, butter, ghee and other fat rich dairy products.
It act as a antioxidant and also as a precursor of vitamin A.
one mole of beta-carotene yields two molecules of vitamin A, while alpha carotene yields
only one.

22. •Dairy animals differ in their capacity to transfer carotene from feeds to
milk fat.
• Cows in general, and some breeds in particular (Such as Jersey), can
transfer more carotene from their feed to the milk fat than buffaloes.
• Hence buffalo milk is white in colour. The carotinoid content of
buffalo milk varies from 0.25 to 0.48/ ug/g, while that of cow milk may
be as high as 30/ ug/g of milk.
• Riboflavin besides being a vitamin, is a greenish-yellow
pigment which gives the characteristics colour to whey.

23. d) Enzymes: These are biological catalysts which can hasten or retard any chemical changes
without themselves participating in the reactions. the enzymes are protein like,
specific in their actions, and inactivated by heat. Each enzymes has its own
inactivation temperature. The important enzymes and their specific actions are as
follows:
1) Analase (Diastase) : Starch splitting
2) Lipase : fat splitting, leading to rancid flavour
3) Phosphate: Capable of splitting certain phosphoric acid esters
4) Protease: Protein splitting
5) Peroxidase and Catalase : Decomposes hydrogen peroxides

24. e) Vitamins: Although present in foods in very minute quantities, these are vital for the
health and growth of living organisms.
• Fat soluble vitamins A, D, E and K
•Water soluble vitamins of B complex group (such as thiamine or B1, riboflavin or B2,
Pantothenic acid niacin pyridoxine or B6 biotin, B12 folic acid etc. and vitamin C
(ascorbic acid).
Absence of vitamins in the diet over a prolonged periods causes ‘deficiency
diseases’.

29. References
1. Milk and Milk Products – Winton and Winton (1993), Agrobios (India), Agro. House,
Behind Nasrani Cinema, Chopsani Road, Jodhapur
2.Milk Testing – Davis J. G. Agrobios (India), Agro. House, Behind Nasrani Cinema, Chopsani
Road, Jodhapur.
3.Chemistry of Milk and Milk Products – Singh V. B. (1965), Asian Publishers, New mandi,
Muzaffarnagar.
4.Dairying in India – Gupta, H. A. (1997) Kalyani Publisher, 1/1 Rajinder Nagar, Ludhiana.
5.Outlines of Dairy Technology – Sukumar De (2000) Oxford University Press, New Delhi

30. THANK YOU