Vitamins hydrosoluble

Vitamins Vitamins are organic compounds essential for the correct development of organisms. Therefore, foods, and especially milk, must supply them at the needed amounts. Normal values of vitamins in human and cow milk are summarized in Table 13.5. In general terms, vitamins can be classified as hydrosoluble and liposoluble. According to this feature, the liposoluble A, D, E, and K vitamins are in fat globules, while the remaining vitamins are in milk plasma. 

The amino acid composition of sunflower meal is generally balanced. The energy content of sunflower meal compares favorably with other oilseed meals. The energy value of a sunflower meal increases with increasing residual oil content and a reduction of the fiber content. Sunflower meal is also valuable as a calcium and phosphorous source and a good source of hydrosoluble B complex vitamins. 

The hydrosoluble vitamins are needed as enzyme cofactors. The vitamin can have one or a few very specific roles or much more extensive roles. Several B group vitamins serve as coenzymes for enzymes with fimction in the catabolism of foodstuffs to produce energy for the body. Some of them are fimdamental even for their antioxidant activity and other health benefits. Thus low levels of some B group vitamins (B2, Bg, B12) can result in reduced levels of DNA methylation and therefore in some kinds of cancer (Hernandez et ah, 2003). 

Rocha, F.R.P., Filho. O.F., and Reis, B.F., 2003. A multicommuted flow system for sequential spectrophotometric determination of hydrosoluble vitamins in pharmaceutical preparations. Talanta. 59 191-200. 

Determination of hydrosoluble vitamins (AA, thiamine, riboflavin, and pyridoxine). The flow manifold is designed with computer-controlled three-way solenoid valves... 

The recommended daily allowances of hydrosoluble and Uposoluble vitamins, according to age and physiological stage, are summarized in Table 17.5. 

There are many factors that lower nutrient availability in packaged and stored foods. Environmental factors such as the presence of oxygen and light, or processing variables such as temperature, time, pH, and oxidizing and reducing agents affect the stability of nutrients like amino acids and vitamins (Borenstein et al. 1990, Harris 1977). Table 17.6 summarizes the susceptibility of hydrosoluble and liposoluble vitamins to these factors. 

Ascorbic acid Vitamin C, which is hydrosoluble and prevents scurvy. The sodium ascorbate is used with potassium bromate as a dough conditioner to strengthen and condition yeast-leavened breads. 

Wort Hydrosoluble material derived from the mashing of barley malt and brewing adjuncts rich in fermentable carbohydrates, dextrins, and other soluble compounds (amino acids, peptides, B vitamins, etc.). The beer wort also contains soluble compounds extracted from hops including polyphenols, humulones, lupu-lones, resins, and tannins. The wort, upon fermentation, yields beer. 

Although vitamins have different structures, sources, requirements, and mechanisms of action, they are classified according to their solubility in water or in fats. Vitamins A, D, E, and K are liposoluble, whereas the B-complex (Bi, B2, Bg, B12, niacin, pantothenic acid, biotin, and folic acid) and C vitamins are hydrosoluble. Moreover, there are some organic compounds related to vitamins that are usually classified with the B vitamins and are also hydrosoluble i.e., p-aminobenzoic acid is included among these substances with similarities to vitamins. 

To date, only some hydrosoluble vitamins are known to interact as ligands with metal ions and, with some exceptions, very few solid phase stmctures of these complexes have been obtained (Scheme 2). Indeed, only a few cadmium complex structures have been described. 

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