Title : Effect of preparation methods on chemical composition and aflatoxin content of peanut products
Peanut production in Indonesia is predominantly used for food. Therefore, information on nutritional aspects and aflatoxin contamination in peanuts is essential in terms of food security and food safety. Preparation of peanuts into food products normally involves heat treatment, the use of water, spices, and microorganism that may affect the nutrient and aflatoxin contents. Hence, the effect of preparation methods on the chemical composition and aflatoxin content of selected peanut food products was studied in the Food Chemistry and Technology Laboratory of ILETRI, Malang. The peanut pods harvested from farmer practices in Ponorogo, East Java were stored for one month, then the kernels were prepared into deep-fried peanut, pressed-fried peanut, peanut sauce, peanut press cake (defatted peanut), fermented peanut press cake (peanut tempe) and fried peanut tempe. The trial was a randomized complete design with three replicates. Observations included physical and chemical characteristics of peanut kernels, chemical composition of peanut products and aflatoxin content using ELISA method. The results showed that peanut kernels contained 26.3% of protein (dw) and 50.4% of fat (dw) with relatively low aflatoxin B1 content (9.1 ppb) due to low moisture level (5.6%), no A.flavus infection and high sound/intact kernels (73.1%). Peanuts prepared into peanut tempe showed the highest increase in protein content, followed by fried peanut tempe, peanut press cake, and pressed-fried peanut, while fat content decreased in all products. The preparation of deep-fried and pressed-fried peanuts decreased aflatoxin B1 by 26.4% and 41.8%, respectively, while no significant differences were noted in peanut sauce and peanut press cake preparation. Aflatoxin B1 increased two-fold during peanut tempe preparation, however it significantly decreased by 38.9% after deep-fried. Excluding peanut tempe, all peanut products contained aflatoxin B1 below the permitted maximum level (15 ppb), therefore safe for consumption.