Lactose is the natural carbohydrate source and prebiotic compound found in the milk of mammals, but large variations in lactase activity in the small intestines of adult populations carl cause problems with its use. The value of lactose can be increased by hydrolysis, bur even more valuable products can be made by changing the structure of lactose and preventing its absorption in the gut. Some of these nonabsorbable lactose derivatives are already used in medical and functional food applications. Calcium phosphate precipitation to the heat-transfer surfaces is one of the oldest problems of the dairy industry but if precipitation is carried out in controlled conditions, the precipitate can be further processed to form milk calcium powder: Milk calcium can be used as a natural source of calcium in calcium-fortified dairy products. The mineral and salty taste of whey has reduced its Else as a food ingredient. The use of modern membrane technology offers a means of producing whey salt as a by-product of whey demineralization. These otherwise wasted minerals can then be used as a natural( mineral salt. Especially interesting is the possibility of recycling the whey, salt into cheese, improving its nutritional status.
