The ability of the basidiomycete Hericium erinaceum to degrade starch and upgrade nutritional value of cornmeal during
solid-state fermentation was studied. On the basal medium which consisted of cornmeal and salt solution, H. erinaceum
produced a strong a-amylase on the 15th day after inoculation, which resulted in a 52% degradation of the starch. By
supplementation with 5–15 g soybean meal per 100 g cornmeal the a-amylase activity and degradation rate of starch was raised
significantly ( P < 0.01). Prolongation of fermentation time from 15 to 30 days did not increase significantly the degradation rate
of starch, though the a-amylase activity reached its maximum value of 179 U/g on the 20th day after inoculation. Under
conditions close to the theoretical optimum fermentation conditions, that was after 25 days at 25 jC in the medium with added
15 g soybean meal per 100 g cornmeal, the starch content in the product decreased from 63% to 22% ( P < 0.001) and protein
content increased from 12% to 17% ( P < 0.01). In the protein in the product, the lysine content was increased from 36 to 56 mg/
g and tryptophan from 9 to 13 mg/g. Using egg protein as a standard, an evaluation on the protein quality of the fermented
product showed that it was superior to that of the nonfermented control and to other cereals, was close to that of soybean and
chicken, but was inferior to that of milk and red meats.
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