A Study of the Chemical and Physical Changes of the Sudanese Groundnuts during Storage

Abstract

Abstract Groundnut is one of the main important oil seed crops in the Sudan. The research is an attempt to study the chemical changes, which may occur in the main Sudanese groundnuts varieties Ashford and Spanish. The storage had been carried using fresh produced groundnuts in both jute bags and plastic containers. The samples had been stored in a warehouse in Port Sudan town for one-year period, under the normal conditions. Using ofjutes bags expected to give an ideal example of the traditional methods of storing groundnuts in the Sudan. Plastic sealed containers had been chosen for their properties as heat isolators to preserve the samples under controlled conditions, and so as to resemble storing in concrete Silos which known of their good presen/ation abilities (heat isolator and do not condensate water vapors). The storage of the groundnuts samples was started on 1.01.03 and finished on 31.12.03 under the normal condition (moisture, temperature, relative humidity and other affecting factors air, light and insect). The stored samples were tested before storage and every three months thereafter. The tests were made on the pure seeds to avoid miss-leading results. Physical tests were carried on the whole seeds using industrial specifications which usually demanded forthe exported ground nuts: split kemels, shriveled kemels, impurities ,blanched kemels ,discolored kemel insect damaged kernels ,sound seeds ,count ,weight of 1000 kemel, insect count per kg and hectoliter. Chemical tests were done on the ground nuts seed meat after grinding and applying intemational procedures forthe following tests: protein ,oil content ,aflatoxins ,moisture and ash. Also the chemical tests were carried on the extracted ground nuts oil using the same procedures fortesting: free fatty acids, peroxide value, oil color ,saponification value and oil refractive index. The ground nuts samples stored in bags had been heavily deteriorated after one year period storage under normal storage factors, while the samples stored in plastic containers under the same storage factors revealed less quality changes and better preservation seed quality. The two ground nuts varieties had shown van'able and different quality changes under the same storage conditions.