Vitamins are organic chemicals required by the body in trace amounts but which cannot be synthesized by the body. The vitamins required for growth and maintenance of health differ between species; compounds regarded as vitamins for one species may be synthesized at adequate rates by other species. For example, only primates and the guinea-pig require ascorbic acid (vitamin C; section 6.4) from their diet; other species possess the enzyme gluconolactone oxidase which is necessary for the synthesis of vitamin C from D-glucose or D-galactose

The salts of milk are mainly the phosphates, citrates, chlorides, sulphates, carbonates and bicarbonates of sodium, potassium, calcium and mag- nesium. Approximately 20 other elements are found in milk in trace amounts, including copper, iron, silicon, zinc and iodine. Strictly speaking

4.7.I Occurrence and microheterogeneity B-Lactoglobulin is a major protein in bovine milk, representing about 50% of total whey protein and 12% of the total protein of milk. It was among the first proteins to be crystallized, and since crystallizability was long considered to be a good criterion of homogeneity, B-Ig, which is a typical

Normal bovine milk contains about 3. 5% protein. The conce changes significantly during lactation, especially during the first ft post-partum(Figure 4. 1); the greatest change occurs in the whey fraction(Figure 4.2). The natural function of milk proteins is to supply

The stability, or instability, of the milk fat emulsion is very significant with respect to many physical and chemical characteristics of milk and dairy products. The stability of the emulsion depends strongly on the integrity of

The milks of all mammals contain lipids but the concentration varies widely between species from c. 2% to greater than 50%(Table 3. 1). The principal function of dietary lipids is to serve as a source of energy for the neonate and the fat content in milk largely reflects the energy requirements of the species, e.g. land animals indigenous to cold environments and marine

Lactose is the principal carbohydrate in the milks of all mammals; non mammalian sources are very rare. Milk contains only trace amounts of other sugars, including glucose(50 mg\), fructose, glucosamine, galac- tosamine, neuraminic acid and neutral and acidic oligosaccharides The concentration of lactose in milk varies widely between species(Table 2.1). The lactose content of cows'milk varies with the breed of cow

Milk is a fluid secreted by the female of all mamalian species, of which there are more than 4000, for the primary function of meeting the complete nutritional requirements of the neonate of the species. In addition, milk serves several physiological functions for the neonate. Most of the non- nutritional functions of milk are served by proteins and peptides which

ELECTRONIC NOSE SYSTEMS Odorant molecules Chemical Information CIM Coated Sensor Raw electrical signal Sensor processor Processed electrical signal Signal processor Denoised Electrical signal

第一章 绪论 第二章 食品的热处理与杀菌 第三章 食品的低温处理与保藏 第四章 食品的脱水加工 第五章 食品辐射保藏 第六章 食品的腌渍烟熏和发酵处理 第七章 食品的化学保藏 第八章 典型食品的加工工艺