采用大豆、小麦、豆粕、面粉及麸皮按不同配比复合用于发酵酱油成曲,分别测定成曲的蛋白酶活力、淀粉酶活力、β-葡萄糖苷酶活力及总酚含量,并评价了各酱油成曲及原料配比对DPPH、ABTS+自由基清除能力和还原力的影响。结果表明,原料配比为m(大豆)∶m(面粉)∶m(麸皮)=4∶0.8∶0.2的成曲清除DPPH自由基能力最高,m(大豆)∶m(面粉)=4∶1的成曲清除ABTS+自由基的能力、还原能力和总酚含量最高。原料经过米曲霉固态发酵后,DPPH自由基清除能力提高了10倍以上,ABTS+自由基清除能力可提高5倍以上,还原能力提高了4倍以上,总酚含量也提高了3倍多。采用大豆所制作的酱油成曲的抗氧化性比豆粕所制作的酱油成曲的抗氧化性高,添加麸皮有利于提高成曲清除DPPH自由基的能力。

Soybean,wheat,meal,flour and wheat brans with different ratios were used to ferment four soy sauce koji,and the protease activity、amylase activity,β-glucosidase activity and the total phenolic content of the four soy sauce koji were measured respectively.Then the four soy sauce koji and the raw materials were assayed through these methods: DPPH radicals,ABTS + radicals and reducing power.The results revealed that Koji with ratio of soy: wheat flour: wheat bran = 4∶ 0.8∶ 0.2 had the highest DPPH radical scavenging capacity.Koji with ratio of raw materials for soy: wheat flour = 4∶ 1 had the highest ABTS + radical scavenging capacity,reducing power and the highest content of total phenolic.After solid fermentation of Aspergillus oryzae,DPPH radical scavenging capacity increased by 10 times,ABTS + radical scavenging capacity by 5 times,reducing power by 4 times and the content of total phenolic increased by 3 times.Soy sauce koji fermented with the soybean possessed stronger anti-oxidant activity than meal,and adding wheat brans could help improve DPPH radical scavenging capacity of the koji.