糙米酵素混菌发酵工艺优化

为促进混合发酵的糙米酵素中酿酒酵母和植物乳杆菌快速生长,以活菌数为指标对传统糙米酵素发酵培养基组分进行优化,并研究各因素之间的交互作用。由预试验确定各组分适宜浓度范围后通过Plackett-Burman试验得出3个重要影响因子:蜂蜜、糙米和NaCl。根据3个重要影响因子的效应大小设定最陡爬坡试验的方向和步长,采用Box-Behnken试验设计3因素3水平的响应面分析试验。优化后的混菌最佳发酵培养基的组成成分为蜂蜜3.38g/100 mL、糙米10.71g/100mL、NaCl 0.24g/100mL、小麦芽0.25g/100mL、大麦芽0.50g/100 mL、(NH_4)_2SO_40.50g/100 mL和茶叶粉0.025g/100mL。采用以上最佳发酵培养基进行验证实验得出活菌数为5.35×10~7 CFU/mL,是基础糙米酵素培养基活菌数(5.71×10~6 CFU/mL)的9.37倍。验证实验说明响应面法优化得到的函数模型与实际数据较为拟合。

Optimization on mixed fermentation process with brown rice ferment

The mixed fermentation process of enzymatic brown rice was optimized by the response surface method. In order to optimize the growth of Saccharomyces cerevisiae and Lactobacillus plantarum in short-term mixed fermented brown rice, the fermentation medium components of the traditional brown rice enzyme were optimized and the interaction between the constituent components was analyzed. Firstly, the main factors were analyzed by pre-experiemntal. The vital influencing factors of biomass, such as honey, brown rice and NaCl, were determined by Plackett-Burman test. The direction and step size of the steepest climbing test are set according to the three important factors effect intensity. Finally, the Box-Behnken test was used to design a 3-factor 3-level response surface analysis test. The optimum fermentation medium was honey 3.38 g/100 mL, brown rice 10.71 g/100 mL, NaCl 0.24 g/10 0mL, malt 0.25 g/100 mL, barley germ 0.5 g/100 mL, (NH₄)₂SO₄ is 0.5 g/100 mL, tea powder 0.025 g/100 mL. After cultivating with the above culture medium, viable count was 5.35×10⁷ CFU/mL, which was close to the prediction, and was 9.37 times as much as that of basic medium with 5.71×10⁶ CFU/mL.