Preparation method for low-salt high-active-component-content natto through double-bacterium combined fermentation

The invention discloses a preparation method for low-salt high-active-component-content natto through double-bacterium combined fermentation. The invention aims to solve the technical problems of high sodium salt content and poor nattokinase active component in conventional natto. The method comprises the following steps: (1) cleaning beans to be fermented; (2) soaking the cleaned beans with warm water; (3) steaming the soaked beans; (4) conducting inoculation, namely adopting bacillus subtilis and lactic acid bacteria for combined fermentation, and adding CaCl2 in the fermentation process of fermented soybeans in water; (5) making koji; (6) carrying out secondary fermentation; and (7) filling and sterilizing a finished natto product. The natto prepared by the method is low in sodium salt content, high in nattokinase active components and long in shelf life. 本发明公开了一种低盐高活性成分双菌联合发酵水豆豉的制作方法，解决了现有技术中水豆豉中钠盐含量高、纳豆激酶活性成分差的技术问题。它下述步骤：（1）将需要进行发酵的豆类清洗干净；（2）将清洗后的豆类用温水浸泡；（3）将浸泡后的豆类蒸熟；（4）接种，采用枯草芽孢杆菌和乳酸菌联合发酵，水豆豉发酵过程中添加Cacl