Graduate Institute of Food Science and Technology, National Taiwan University, Taipei 10673, Taiwan.
J Biosci Bioeng. 2011 Jul;112(1):49-53. doi: 10.1016/j.jbiosc.2011.03.008. Epub 2011 Apr 15.
In this study, sufu, a Chinese traditional fermented product of soybean, was prepared by ripening salted tofu cubes in the mash of Aspergillus oryzae-fermented rice-soybean koji possessing various hydrolytic enzymes at 25°C, 37°C and 45°C. Antioxidant activity including 2,2-diphenyl-2-picylhydoxyl (DPPH) radical-scavenging activity, Fe(2+)-chelating ability and reducing power exerted by the methanol extract of sufu was determined and compared with that of the non-fermented tofu extract. It was found that antioxidant activity of the sufu extracts was, generally, higher than the non-fermented tofu extract. Ripening temperature and the duration of ripening period affected the antioxidant activity of the sufu extracts. Taking into account of extraction yields, the sufu product ripened at 45°C for 16 days showed the most profound enhancement in the DPPH radical-scavenging effect and Fe(2+)-iron-chelating ability, which is 3.4 and 11.5 folds, respectively, that noted with the non-fermented tofu.
在这项研究中，腐乳是通过在 25°C、37°C 和 45°C 的条件下，让盐渍豆腐块在米-豆曲-米曲霉发酵而成的混合物中成熟来制备的。该混合物含有各种水解酶。腐乳甲醇提取物的抗氧化活性（包括 2,2-二苯基-2-苦基肼基（DPPH）自由基清除活性、Fe(2+)-螯合能力和还原能力）与非发酵豆腐提取物的抗氧化活性进行了测定和比较。结果表明，腐乳提取物的抗氧化活性通常高于非发酵豆腐提取物。成熟温度和成熟时间会影响腐乳提取物的抗氧化活性。考虑到提取产率，在 45°C 下成熟 16 天的腐乳产品对 DPPH 自由基清除效果和 Fe(2+)-铁螯合能力的增强最为显著，分别是未发酵豆腐的 3.4 倍和 11.5 倍。
