Changes in Selected Chemical and Antinutritional Components during Tempeh Preparation Using Fresh and Hardened Common Beans

A tempeh‐type fermented product was prepared from fresh and hard‐to‐cook (HTC) common beans. Fermentation decreased fat and fiber content and increased soluble solids, total and soluble proteins, soluble carbohydrates and pH of both bean samples. About 12% of solids were reduced during 72 hr fermentations. Results suggested that Rhyzopus oligosporus was capable of hydrolyzing the trypsin inhibitor and phytic acid of the substrate. Lectin and tannin contents decreased as a result of treatments applied during substrate preparation. Fresh and HTC beans may be converted by this fermentation technique into products of higher quality.