Physico-chemical effects of gamma radiation on peanut (Arachis hypogaea L.) and the feasibility of the use of its skin as natural antioxidant

Abstract

Gamma radiation is efficient to eliminate the fungal contamination in peanut kernels, having a beneficial effect by the elimination of the aflatoxigenic fungi. The peanut has a high concentration of lipids and other macro and micronutrients of nutritional benefit, like natural antioxidants. Several studies show us that the irradiation causes molecular changes that can have both positive as negative effects in the treated products, depending on the doses used. The antioxidants are among the chemical compounds of interest in peanut kernels, once it goes through periods of storage and lipids can be oxidized, which influences the quality of the final product. We are already exporting blanched peanuts that has higher value in the international market, however, nowadays the residues of the blanching has use only in the animal feed. This research has goals such evaluation of the lipid quality in irradiated peanut, Runner 866 cultivar, under doses of (0, 5.0, 7.5 and 10.0 kGy) and stored for twelve months correlating the blanching effect of this product; submit skin, that is the blanching residue, under the same doses of radiation and evaluate it as a source of natural antioxidant, compared with synthetic antioxidants used in industries like BHT and TBHQ. In peanut kernels will be evaluated the color, chemical composition, acid index, peroxide index, oxidative stability in rancimat, UV absorptivity, fatty acid composition, total phenolic, total flavonoids, condensed tannins, antioxidant activity, tocopherols and potentially aflatoxigenic fungi. In the skin, the blanching residue, will be evaluated the color, totals phenolic, condensed tannins, antioxidant activity and water activity. (AU)