1. Milk  Nutritive Value An excellent source of calcium and phosphorus High in protein Low in iron Vitamin A and D added Source of riboflavin  Properties of milk Colloid properties – milk is made of 2 types of small particles which are mixed together but will separate upon sitting (cream rises to top), homogenization stabilizes this emulsion Casein – protein in milk Lactose – sugar in milk

2. Milk Processing  Pasteurization – heat milk t 72° C for 15 seconds to kill harmful bacteria  Homogenization – forcing milk under pressure to break up large fat globules so that they stay suspended in the milk, therefore, milk and cream will not separate  Fortification – Vitamin A and D are added back after processing

3. Forms of Milk  Fresh Homo or whole – 3.5% butterfat 2 % (partly skimmed) – half of the fat is removed therefore leaving 2% in the milk 1% - 1% fat remains Skim – most of the fat is removed; same nutritive value as whole with half the calories Vico/Chocolate – chocolate syrup is added to 2% milk; more costly and more calories

4.  Concentrated Evaporated – either skim or whole with half water removed; stored in cans; needs no refrigeration; used in remote areas; can disguise the flavour with spices Condensed – sugar is added to whole milk before it is evaporated; high in calories; used in candy and squares Powdered – has both fat and water removed; is inexpensive; convenient; once reconstituted, has same nutritive value as whole without the calories

5.  Fermented Buttermilk – in pioneer days, liquid remaining after churning butter; today, a bacteria is added to 2% which thickens and gives a slight sour flavour Yogurt – made from 2%; soft solid consistency

6.  Cream products Half and half – blend of milk and cream; 10% fat Coffee cream – 18-20% fat Whipping cream – 36-40% fat Butter – most concentrated source of fat 80% Ice cream/ice milk – air is whipped into cream and milk to prevent ice crystals from forming; ice milk has same amount of protein and calcium as equal amount of milk but with twice as many calories because of the sugar; ice cream has even more calories

7. Milk cookery and preparation  Curdling – foods with acids, tannins (acid in potatoes) and salts may cause curdling (clumping together of protein molecules)  Scum formation – protein coagulation; may cause milk to boil over  Ways to prevent curdling: Add acid to milk gradually Heat acid and add to cold milk Heat together for only a short period of time Add acid to a sauce (rue), then add to milk

8. Tips for Heating and Cooking Milk  Use double boiler  Use low heat  Use microwave