Abstract
Tofuyo (traditional fermented food of Okinawa) was produced using mushrooms instead of Monascus sp. and Aspergillus oryzae. To screen mushrooms that produce alcohol-tolerant protease, 76 strains of edible mushroom were cultivated on rice medium and total protease activity was measured in the presence of 20% ethanol. Ten strains of mushroom, such as Auricularia sp. SKB074 (4.46 U / L) and Auricularia americana SKB073 (4.03 U / L), showed higher activity than that of commercial rice-koji (1.46 U / L). Culture conditions and preliminary fermentation tests were investigated, and Auricularia auricula-judae NBRC100150 and Lepista sordida SKB010 were selected to produce tofuyo based on the taste and aroma of the prototype. Tofu was fermented using mushroom-koji of these strains in the presence of alcohol, and the texture of the produced tofuyo was evaluated using the texture profile method. Tofuyo fermented for 14 or 28 days using L. sordida SKB010 showed texture parameters comparable to those of commercial tofuyo. Tastes and aromas of tofuyo fermented by L. sordida SKB010 showed less distinctiveness, and depending on the alcohol and seasoning used, commercialization as tofuyo with new characteristics might be possible.
