At very high temperatures the calcium phosphate may precipitate out of solution which causes irreversible changes in the casein micelle structure.Įxposure to light will decrease the riboflavin and vitamin A content in milk. This does not affect the nutritional properties of milk minerals. This process is reversible at moderate temperatures. Riboflavin is a heat stable vitamin and is not affected by severe heat treatments.Ĭalcium phosphate will migrate in and out of the casein micelle with changes in temperature. Thiamin is reduced from 0.45 to 0.42 mg/L, vitamin B 12 is reduced from 3.0 to 2.7 µg/L, and vitamin C is reduced from 2.0 to 1.8 mg/L ( Potter et al., 1984). However, the higher heat treatment used in ultra high temperature (UHT) pasteurization for extended shelf combined with the increased storage life of these products does cause losses of some water-soluble vitamins. The mild heat treatment used in the typical high temperature short time (HTST) pasteurization of fluid milk does not appreciably affect the vitamin content. Effects of Heat Treatments & Light Exposure on the Vitamin & Mineral Content in Milk Milk contains small amounts of copper, iron, manganese, and sodium and is not considered a major source of these minerals in the diet.
The fact that calcium and phosphate are associated as salts bound with the protein does not affect the nutritional availability of either calcium or phosphate. In milk approximately 67% of the calcium, 35% of the magnesium, and 44% of the phosphate are salts bound within the casein micelle and the remainder are soluble in the serum phase. Many minerals in milk are associated together in the form of salts, such as calcium phosphate. Milk is a good source of calcium, magnesium, phosphorus, potassium, selenium, and zinc. The specific content of minerals in milk is listed in the Nutrient Content Tables in the Nutrition Facts section. Minerals have many roles in the body including enzyme functions, bone formation, water balance maintenance, and oxygen transport. Milk contains small amounts of vitamins E and K and is not considered a major source of these vitamins in the diet. Fortification of all milk with vitamin D is voluntary. Reduced fat (2% fat), lowfat (1% fat), and skim milk must be fortified with vitamin A to be nutritionally equivalent to whole milk. The content level of fat soluble vitamins in dairy products depends on the fat content of the product. Milk contains the fat soluble vitamins A, D, E, and K. Milk contains small amounts of niacin, pantothenic acid, vitamin B6, vitamin C, and folate and is not considered a major source of these vitamins in the diet. Milk is a good source of thiamin, riboflavin and vitamin B12.
Milk contains the water soluble vitamins thiamin (vitamin B1), riboflavin (vitamin B2), niacin (vitamin B3), pantothenic acid (vitamin B5), vitamin B6 (pyridoxine), vitamin B12 (cobalamin), vitamin C, and folate. The specific content of vitamins in milk is listed in the Nutrient Content Tables in the Nutrition Facts section. They help the body use carbohydrates, protein, and fat. Vitamins have many roles in the body, including metabolism co-factors, oxygen transport and antioxidants. For more details on the vitamins and minerals in milk, see references by Flynn et al. A description of the nutritional function of vitamins and minerals is provided on the Nutritional Components in Milk page in the Nutrition Facts section. This page describes the Vitamins and Minerals present in milk, and the Effects of Heat Treatments and Light Exposure on the Vitamin and Mineral Content in Milk.
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