Ying-ying Ma, Qing-bin Liu, Xiao-qing Zhou and Jian-gang Yang
Natto is a kind of food taking soybean as raw material and generated by bacillus natto fermentation. Natto is especially applicable to the old and children due to high nutritive value and healthcare function. With time going on, natto will produce odorous ammonia flavor with its color deepening and bitter taste coming out which has a strong impace on product’s taste and appearance because of short guarantee period. The pape mainly start with process optimization and preservation to determine optimal experiment condition for natto manufacturing technique by single factor experiment and orthogonal experiment. On this condition, conduct preservation experiment by adding corrosion remover sodium benzoate and conduct sensory evaluation and measure natto kinase activity and natto total plate count through regarding 10 days as a period and study influence of sodium benzoate on natto guarantee period. Results display that optimal manufacturing technique condition is 39?¢????? culture temperature, 13h fermentation time and 11% inoculum size and when additive amount of sodium benzoate is 0.25g/kg, natto guarantee period can be lengthened