Milk Products and Alternatives n Milk u u

Milk Products and Alternatives n Milk u u Complete protein source Colloidal dispersion—large proteins in aqueous serum t Lactose, minerals, fat dispersed in serum t Fat is in an emulsion

Milk Products and Alternatives n Composition of cow’s milk: H 2 O u Fat u Lactose u Proteins u Minerals u 87% 3. 7% 4. 9% 3. 5% 0. 7%

Milk Products and Alternatives n Proteins in milk u u Casein (curd)— 82% t Micellular t Coagulates with added rennin or acid Lactoglobulin (whey)— 18% t Serum t Curdle-resistant but denatures with heat >158°F

Milk Products and Alternatives n Vitamins and minerals in milk u u Vitamins t Vitamin D, vitamin A, and riboflavin Minerals t Ca, P, Mg, K, Na

Milk Products and Alternatives n Safety—milk is highly perishable u Pasteurization t Standard method: 145°F, 30 minutes t HTST: 162°F, 15 seconds t Ultrapasteurized: 275 -300°F, 2 -4 seconds • Half and half, cream, and eggnog t UHT: 280°F, 2 seconds • Sterile, stored on shelf

Milk Products and Alternatives n Safety continued… u Homogenization t Optional t Decreases globule size t Prevents separating

Milk Products and Alternatives n Fat grades and varieties of milk Whole 4% fat u Reduced 1 -2% fat u Skim 0. 1 -0. 2% fat u Condensed t NFDM— 100% H 2 O removed t Evaporated— 60% H 2 O removed t Sweetened— 40 -45% sugar u

Milk Products and Alternatives n Fermented dairy products Unrefrigerated u Soured by lactic acid bacteria u Casein micelles aggregate u Types: t Yogurt t Buttermilk t Sour cream t Cottage cheese u

Milk Products and Alternatives n n Yogurt u Mixed culture of bacteria u 113°F for 4 hours Buttermilk u Skim milk u Utilizes bacteria for buttery flavor u Cooler and longer incubation time than yogurt Sour cream u Vinegar or buttermilk added w/ or w/out bacteria Cottage cheese