Peanuts phytic acid

Minor Constituents. All four oilseeds contain minor constituents that affect the use of the defatted seeds, especially in feeds and foods. Percentages of phytic acid [83-86-3] (3), for example, are soybean, 1.0—1.5 (30) cottonseed kernels, 2.2—3.8 (25) peanut kernels, 0.8 (25) and sunflower, 1.6-1.7 (31). 

Although A. flavus will grow on almost any natural or processed substrate, aflatoxin occurs naturally primarily in corn, peanuts, cottonseed, grain sorghum, tree nuts, millet, copra, and figs (34). Substrate factors must be involved in contamination, since it is limited to a relatively small number of agricultural commodities. The restricted access of zinc has been proposed as an explanation for the inability of A. flavus to elaborate aflatoxin in soybeans (35). The availability of zinc for aflatoxin biosynthesis appears to be blocked by the presence of phytic acid in soybeans (36). 

Phytic acid and camosine (histidine-containing dipeptide), obtained from cereal and meat by-products, are effective inhibitors of hpid oxidation by several mechanisms, including metal inactivation and free radical quenching. Uric acid obtained from the decomposition of adenosine triphosphate in muscle also inhibits lipid oxidation by the same mechanisms. However, the importance of uric acid as an endogenous antioxidant in muscle foods is not clear. Various protein concentrates from soybeans, cottonseed and peanuts inhibit hpid oxidation in muscle foods. In addition to their iron binding activity, these crade extracts contain complex polyphenolic flavonoids that have potent antioxidant activity. 

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