Food additives folic acid

In terms of amino acids bacterial protein is similar to fish protein. The yeast s protein is almost identical to soya protein fungal protein is lower than yeast protein. In addition, SCP is deficient in amino acids with a sulphur bridge, such as cystine, cysteine and methionine. SCP as a food may require supplements of cysteine and methionine whereas they have high levels of lysine vitamins and other amino acids. The vitamins of microorganisms are primarily of the B type. Vitamin B12 occurs mostly hi bacteria, whereas algae are usually rich in vitamin A. The most common vitamins in SCP are thiamine, riboflavin, niacin, pyridoxine, pantothenic acid, choline, folic acid, inositol, biotin, B12 and P-aminobenzoic acid. Table 14.4 shows the essential amino acid analysis of SCP compared with several sources of protein. 

Immunosensors have been developed commercially mostly for medical purposes but would appear to have considerable potential for food analysis. The Pharmacia company has developed an optical biosensor, which is a fully automated continuous-flow system which exploits the phenomenon of surface plasmon resonance (SPR) to detect and measure biomolecular interactions. The technique has been validated for determination of folic acid and biotin in fortified foods (Indyk, 2000 Bostrom and Lindeberg, 2000), and more recently for vitamin Bi2. This type of technique has great potential for application to a wide range of food additives but its advance will be linked to the availability of specific antibodies or other receptors for the various additives. It should be possible to analyse a whole range of additives by multi-channel continuous flow systems with further miniaturisation. 

Folic acid, shown in Fig. 12.3, is a common component of food and vitamins.36 The receptor for the vitamin folic acid is known as the folate receptor or the high-affinity membrane folate-binding protein.37 These folate receptors typically are not present in normal cells, but in a variety of human tumors they are greatly overexpressed.36-38 In addition, folate receptors mediate internalization by endocytosis. For these reasons, folic acid has been examined as a homing device. In general, studies have shown that by simple conjugation of folic acid to macromolecules, internalization into cells can occur similarly to that of free folic acid.39... 

Food and Drug Administration. Food standards amendment of standards of identity for enrichment of grain products to require addition of folic acid. Federal Register 1996 61 8781-97. 

Considerable uncertainty and controversy exists concerning the folate requirement for humans. Hie review of data concerning the human folate requirement by the Food and Nutrition Board (1989) suggests that the daily maintenance requirement is 100-200 fig of avaUable folic acid equivalents. The 1989 RDAs were reduced to 200 and 180 fig for adult men and women, respectively, from the previous RDA of 400 on the basis of such evidence (Food and Nutrition Board, 1989). Similarly, the Canadian RDA for folate was set at 3 /ig/kg body wt or 210 fig for a 70-kg individual. These lower RDAs may be inadequate for certain population groups, however (Sauberlich, 1990 Bailey, 1992 McPartlin etai, 1 3). It is currently difficult or impossible to predict the quantitative effect on folate nutritional status of factors such as (a) changes in folate intake, (b) differences in folate bioavailability, (c) effects of pregnancy and lactation on folate requirements, and (d) pharmaceuticals with antifolate properties. In addition, the development of mathematical models would improve our ability to evaluate methods of nutritional status assessment for this vitamin. 

The mechanisms by which vitamins prevent illnesses are not weU understood, and the amounts needed to lower risks for certain disease conditions may be higher than the current recommended levels for preventing nutritional deficiencies. For example, the Institute of Medicine recommends that to prevent neural tube birth defects, women of child-bearing age should consume 400 Xg of folic acid per day (but not more than 1000 Xg/day) from fortified foods and/or dietary supplements in addition to folates obtained from a varied diet. " < Ascorbic acid intakes of 80-200mg daily (8-20 times the amounts needed to prevent scurvy) may be necessary to enhance certain physiological functions and minimize specific disease risks. " ... 

Haidary SM, Corcoles EP, Ali NK (2013) Folic acid delivery device based on porous silicon nanoparticles synthesized by electrochemical etching. Int J Electrochem Sci 8 9956-9966 Heirlings L, Siro I et al (2004) Influence of polymer matrix and adsorption onto silica materials on the migration of alpha-tocopherol into 95 % ethanol from active packaging. Food Addit Contam 21 1125-1136... 

In 1992, the US Public Health Service issued a recommendation that all women capable of becoming pregnant consume 400 tg of folic acid daily to reduce the risk of having a child born with a neural tube defect (Centers for Disease Control and Prevention 1992). Food fortification was implemented to reduce the number of pregnancies affected by NTDs (Centers for Disease Control and Prevention 2005). Estimates have shown that the additional intake of folic acid through food fortification has been effective in reducing the prevalence of NTDs at birth. 

Foam, 2342, 2776 Focal adhesion kinase (FAK), 2203 Foeniculum vulgare, 2976, 2984 Folate, 1732 Folic acid, 1270 Folk medicine, 3214, 3220 Follicle-stimulating honnone, 1374 Food, 1959, 2391, 3978, 3983, 4112 additives, 337, 3199 colorants, 1816 drugs, 2423 extracts, 1765 industry, 4049 matrix, 2472 poisoning, 286 preservatives, 3976 processing, 2467 sources, 1967, 2527-2557 supplements, 2391 transit time, 1408... 

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