الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The present study was carried out to investigate the effect of processing, cooking and ammoniation on aflatoxin level 1n some Egyptian foods. Peanuts ,rice and beans were used in- this study as they are. widely used in Egyptian diets. To ,obtain contaminated food with a certain level of aflatoxins, samples were inoculated with a spore suspension of a toxigenic strain of Aspergillus flavus which is known to produce afla toxin Bl’ B2 ’ Gl and G2. The aflatoxin content of each sample was determined before and after treatment by the use of thin layer chromatography (TLC) and scanning techniques. Results can be summarized as follows: l.a. Pre-drying of peanuts to.5.5 moisture before inoculation with spore suspension of A.flavus.was the most effective treatment used in this study, causing a reduction of 97 of the total aflatox ins compared with that produced at 12.6 moisture. b. Roastin8 of peanuts in heated sand reduced the total aflatoxins by 66 and aflatoxin El (which is the most toxic and carcinogenic type) by 68. c. Ammoniation for 3,6 and 24 hours reduced the total aflatoxins by 45, 61 ahd 86.5 , respectively. d. Ammoniation of contaminated’~eanuts for 3,6 and 24 hours followed by roasting reduced the total aflatoxins by 82.8, 94 and 96.8, respeotively. 2.a. No growth of Asper~illus flavus was observed in dry beans, but by increasing the moisture’ content of beans, growth was observed and aflatoxins were produced. b. Stewing of contaminated beans was effeotive in the reduction of aflatoxins. The reduotion per cents were increased by increasing the initial moisture content of beans before stewing. The reduction of total aflatoxins were 41, 60 and 82 at 15, 18 and ~ moisture, respeotively. c. The total aflatoxin content of decoated beans was reduced during preparation of the cake (Paste) by 45, and was reduced during frying of the cake in oil (Falafel) by 67. The over all process reduced total aflatoxins by 82. Preparation of Fried bean cakes (Falafel) was more effective in the reduction of aflatoxin than stewing of beans. 3. Washing of contaminated rice ”before cooking reduoed the total aflatoxins by 43, while washing follow ed by cooking reduced it by 86. According to these results it can be concluded that all of the methods used in this study might be effective in the reduction of the’ aflatoxin contents of food to various extent, although none of them was able to destroy the af~atoxin completely. The following was recommended: 1. Drying of food crops-before storage to prevent fungal growth and aflatoxin production. 2. Washing of rice and beans several times with water before cooking, and 3. Imposing limits or tolerence for the aflatoxins concentration in the local and imported foods.