Transcript MILK PRODUCT & NUTRITIVE VALUE

MILK PRODUCT & NUTRITIVE VALUE
Composition of Milk - US Cows
Average (%)
Component
Holstein
Water
87.5
Fat
Range (%)
All breeds
82-91
3.7
2.5-6.0
Solids-not fat 8.8
6.7-11.7
Total solids
9-18
12.5
Composition of Milk - US Cows
Average (%)
Component
Holstein
All breeds
Solids-not fat 8.8
Protein
Range (%)
6.7-11.7
3.2
2.6-4.9
Casein 2.6
2.2-4.0
Others .6
.4-.9
Lactose
Minerals
4.9
.7
3.5-6.0
.6-.8
Composition of Milk - Mammals
Species
Fat % Protein % Lactose %
Human
3.7
Goat
1.6
4.1
7.0
3.7
4.2
W. Buffalo
7.0
3.0
6.0
Horse
1.3
2.2
5.9
Pig
5.3
4.9
5.3
Dog
8.3
7.1
3.7
Whale
46
11
1.3
Composition of Retail Milk
Fat % Solids-not fat %
Whole
3.25
Lowfat
.5-2.0
Skim
8.25
8-12
.0-.5
8-12
Nutritional Value
• Protein – high quality – all essential a.a.
• Casein proteins
– Alpha s1, Alpha s2, Kappa, Beta
• Whey proteins
– Beta-lactoglobulin, Alpha-lactalbumin, Immunoglobulins,
others
Nutritional Value
• Lipids (fats) – high energy
• Essential fatty acids
– Linoleic, linolenic, arachidonic
• Fat soluble vitamins – A,D,E,K
• Triglycerides = glycerol + fatty acids
• Fatty acids from 4-20 C lengths
Nutritional Value
• Lipids (fats) – high energy
• Essential fatty acids
– Linoleic, linolenic, arachidonic
• Fat soluble vitamins – A,D,E,K
• Triglycerides = glycerol + fatty acids
• Fatty acids from 4-20 C lengths
Nutritional Value
• Lactose – milk sugar – only in milk
– 20% as as sweet as sucrose
– Lactase for digestion
– Lactose intolerance – can reduce
• Minerals - Ca, P, K, Na, Cl, S
– Low in Fe, Mn, Cu
• Vitamins
– A, D, E, K and B complex
– Some C
Processing of Milk
• Pasteurization – heating to 145 F for 30 min or 161 F for 15 sec
and cooled promptly to below 45 F
– Destroy micro that cause disease
– Destroy micro that spoil product
– Improve flavor
• UHT – 280 F for 2 sec and cool quickly to below 70 F
Processing of Milk
• Homogenization – milk fat globules broken up into small globules
under pressure to disperse them permanently
• Separation – uses centrifugal force to separate milk components
– Separate cream
Cheese Making
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Standardize milk
Add bacteria
Precipitate protein with rennin or acid
Stir
Cut curd
Heat to expel whey and shrink curd
Remove whey
Salt
Dry and ripen curd
Cheese
• Natural cheese – produced by curd formation using acid or rennin
– Classified based on moisture content
– 30-80% water, 10-30% protein, 0-40% fat
• Pasteurized processed – produced by grinding and mixing and heating one or
more natural cheeses together – American cheese
• Cheese food – blending with no heat, one or more cheeses with other dairy
products such as cream cheese, skim milk or whey
• Cheese spread – cheese food with increased moisture and stabilizers
Butter and Ice Cream
• Butter is made by churning – strong agitation of cream
– 80% fat, 17% water, 1-2% salt, 1-2% curd
– Cultured butter – cream inoculated with Strep. cremoris
• Ice cream
– 10-18% fat, 7-12% SNF, 12-18% sugar