Chemical and Microbial Compositions of Unprocessed and Processed Soybean as Fish Feed Ingredient

Some of fish farm diseases have been linked to feeds and could have link with the ingredients used in compounding them. In this study, 5 kg of soybean seed were purchased and divided into five equal parts. Each part was processed by roasting, toasting, solid state fermentation (SSF), sprouting and other part unprocessed all in triplicate. The SSF and sprouting processing were carried out in a dark room for seven days and pH and Temperature were recorded twice daily. Each of the samples was tested for proximate compositions, phytochemical analysis, microbial load aflatoxin B1 and B2. The results of the study showed that the toasted and roasted soybean were at 120℃ at a time interval of 32-45 minutes. The pH range of 4.0 -5.5 were recorded for soybean during SSF while pH 5.0 to 6.0 for sprouting. Highest coliform counts of 7.79x103 were from fermented soybean while lowest of 4.81 x103 were from toasted soybean. The qualitative and quantitative results showed saponin, tannin, oxalate, alkaloid and glycosides were present though varied according to the processed methods. The proximate compositions varied with the processing methods. The lowest Aflatoxin B1 and B2 of 0.76mg/100g from toasted and 0.46mg/100g from fermented soybean. Based on this toasting method is recommended for processing soybean to reduce phytochemicals, microbial loads, Aflatoxin and increase nutrient compositions.