解淀粉芽孢杆菌发酵豆腐工艺条件优化及营养功能研究

采用高产纤溶酶菌株解淀粉芽孢杆菌CAUNDJ118对豆腐进行发酵,经单因素实验优化获得产纤溶酶活性最优发酵条件:初始水分60%、菌落浓度10~7 CFU/mL、接种量10%、37℃发酵36 h,纤溶酶活性达86.1 FU/g。经发酵后豆腐中总氨基酸含量降低至374.96 mg/g、游离氨基酸和脂肪酸含量分别增加58.8倍和1.1倍,不饱和脂肪酸与饱和脂肪酸比值保持不变。豆腐发酵过程中,其总酚、多肽、还原糖含量、抗凝血活性及DPPH自由基清除活性随着发酵时间延长而增加。因此,解淀粉芽孢杆菌CAUNDJ118发酵豆腐对心血管疾病具有预防或改善作用。

Optimization of fermentation conditions for Bacillus amyloliquefaciens fermented tofu production and research on nutritional and functional properties

In this study, the fibrinolytic enzyme-producing strain Bacillus amyloliquefaciensCAUNDJ118 was used for tofu fermentation. The fermentation conditions were optimized through one-factor experimental design with the fibrinolytic activity as the index. At an initial moisture content of 60%, a colony concentration of 107 CFU/mL, and an inoculum amount of 10%, the fibrinolytic activity reached the maximum of 86.1 FU/g after 36 h fermentation at 37 °C. After fermentation, total amino acid content of tofu was decreased from 421.98 to 374.96 mg/g, while the free amino acid and fatty acid contents was increased by 58.8 and 1.1 folds respectively. No significant changes in the ratio of unsaturated fatty acids to saturated fatty acids were observed before and after tofu fermentation. Tofu fermentation by Bacillus amyloliquefaciens CAUNDJ118 significantly increased the total phenol, polypeptide, and reducing sugar contents. Meanwhile, the anticoagulant activity and DPPH free radical scavenging activity of tofu were increased as the extension of fermentation time. Findings from this study indicated that it would be great potential for the utilization of Bacillus amyloliquefaciens CAUNDJ118 fermented tofu as a novel fermented food for preventing or treatment of cardiovascular diseases.