Effect of a solid‐state fermentation using <i>Rhizopus oligosporus</i> sp.T‐3 on elimination of antinutritional substances and modification of biochemical constituents of defatted rapeseed meal

Abstract

Abstract A solid‐state fermentation of rapeseed using Rhizopus oligosporus was investigated with the purpose of establishing whether fermentation would result in the elimination of antinutritional substances. A 24 h fermentation induced a degradation of 57.7% aliphatic glucosinolates, 97.3% indol glucosinolates and 73% ethanol‐soluble sugars (α‐gaiactosides, flatulence generator included) of rapeseed meal. The fermented meal had a high protein content (348 g kg −1 ). A 24 h fermentation resulted in a net increase in aromatic amino acids and ammonia content. The seed hull could be partially predigested by the enzymes secreted by the mould. The fermentation did not improve the protein efficiency ratio (PER). Rats fed fermented meal had a thyroid weight similar to those of rads fed casein. The protein intake of rats fed fermented meal diet was identical to that of rats fed the dehulled, defatted and heated meal diet. If the combined effects were taken into account, it would appear that the fermentation improved greatly the biological and nutritional value of the obtained products.