MILK PRODUCT & NUTRITIVE VALUE

Composition of Milk - US Cows Average (%)Range (%) ComponentHolsteinAll breeds Water Fat Solids-not fat Total solids

Composition of Milk - US Cows Average (%)Range (%) ComponentHolsteinAll breeds Solids-not fat Protein Casein Others Lactose Minerals

Composition of Milk - Mammals SpeciesFat % Protein % Lactose % Human Goat W. Buffalo Horse Pig Dog Whale

Composition of Retail Milk Fat %Solids-not fat % Whole Lowfat Skim

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 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