Milk has been part of the human diet for thousands of years. Before milk is processed, it is pasteurised – heated to a temperature of 70°C for at least 15 seconds then cooled very quickly to below 10°C. HolsteinUK Education - Milk Pasteurisation kills harmful bacteria and extends the shelf-life of milk.
It is a nutritionally complete food and is a natural product that contains a variety of vitamins and minerals needed for good health. Milk provides a whole range of nutrients essential to growth and development and contains no artificial preservatives or colourings. Milk makes a significant contribution to our diets through the provision of nutrients, vitamins and minerals. Whole milk (milk which has not been processed, apart from pasteurisation,) contains 88% water, 3% protein, 4% fat, 4% sugar and 1% minerals and vitamins. This makes it a very useful food for growth and development. Important vitamins and minerals contained in milk are vitamin D, with calcium and phosphorous being very important for the protection of tooth enamel and bones.
Butter is made from fresh milk and has no artificial additives. It contains Vitamins A, D and E, which are essential for healthy eyes (especially night vision), strong bones and healthy skin. To make butter, cream is shaken – or ‘churned’ – to separate its constituent fat from the water it also contains. The watery by-product produced when churning cream to make butter is known as ‘buttermilk’ and this is used to make margarine and other buttery flavoured spreads.
Cheese is produced by adding an enzyme, rennet, to the milk which causes the curds (milk solids: fat and protein) to separate from the whey (watery portion of the milk). The curds are heated to harden them before they are pressed into a mould and left to ripen (mature) to develop the characteristic flavour of cheese. Well-known British cheeses include Cheddar, Wensleydale, Stilton and Cheshire. The cheeses are usually named after the area where they were first produced. Soft cheeses such as cottage cheese do not go through the ripening process. Cheese is one of the most concentrated sources of key nutrients, including calcium, protein, and vitamins A, B12 and D. While fat content differs among the many different varieties, the average is somewhere around 34%. Not bad for a food that’s not only delicious, but packed with nutrients necessary to build and maintain our bodies. An added plus – eating a piece of cheese after a sugary snack can actually help restore minerals to tooth enamel and protect against tooth decay.
Yoghurt is formed by the bacterial fermentation of milk. It can be made from any milk, but cow’s milk is usually used. Yoghurt is made by adding non-harmful bacteria to the milk to turn it sour. Bacteria cause the sugar in the milk to ferment, which produces lactic acid. This then reacts with the protein in the milk to form yoghurt. It is often flavoured with sugar and fruit. Yoghurt also provides several key nutrients for the body including calcium, protein and vitamin B2.