ABSTRACT

One hundred and twenty five (125) different soyabean flour samples were prepared using different processing treatments viz; steaming, roasting, sprouting, boiling and their combinations for a period ranging from 0 to 72 hrs for separating and 0 to 40 mins for other treatments. These samples were analyzed for their levels of anti-nutritional factors (trypsin inhibitor, haemagglutinin and oligosaccharides — raffinose and stacchyose). From the data obtained, the percent (%) reduction levels of these anti-nutritional factors were determined with reference to the anti-nutritional levels of the raw, untreated soyabean samples. The result showed that samples roasted alone for 40mins gave the least reduction in the anti-nutritional factors studied of 46.35 %, 2 1.17% and 20.00% for trypsin inhibitors, haemagglutinin and oligosaccharides content, respectively. With the exception of samples boiled for 40 mins with the highest reduction of haemagglutinin level (53.76%), samples steamed for 40mins gave the best result among the single treatments, 77.06% for trypsin inhibitor, 36.21% for haemagglutinin and 42.20% for oligosaccharides, with significant difference existing among the haemaggalutinin levels for the two samples. The combined treatments of steaming and roasting for 40mins respectively gave the highest reduction in the anti-nutritional factors studied but for the combined treatments of boiling with roasting for 40mins which gave the highest reduction in haemagglutinin level, with a level of significant difference existing (at p< 0.05) among the two samples.