防止微生物引起食醋返浑的初步研究

摘要

食醋中的微生物是影响食醋返浑的因素之一，研究样品主要污染的微生物是葡糖杆菌属和芽孢杆菌属。经检测该食醋中微生物指标大大超过了国家食醋的卫生指标，达到了55000 cfu／mL。在灭菌的醋液中对微生物进行强化实验后得出以下结论：当分别添加两种菌，菌数低于10 cfu／mL 时，食醋返浑时间为40天左右；当添加芽孢杆菌和葡糖杆菌，菌数在105 cfu／mL 时，食醋返浑时间分别在2天和8天左右，沉淀物干重达到0．942，0．753 g／dL，芽孢杆菌比葡糖杆菌更容易使食醋发生返浑现象，大量的芽孢杆菌还使醋液发臭。通过分别添加1 g／kg 苯甲酸钠于含有105 cfu／mL 芽孢杆菌和葡糖杆菌的醋液中，可以分别延长返浑时间7天和4天。%Microorganism is one of the factors that cause vinegar turbidity.The main polluted microbes in the researched specimens belong to Bacillus cohn and Gluconobacter asia , and the number of cultivable microorganism is about 55000 cfu/mL,which exceeds the national hygienic standard for vinegar.Through adding different number of isolated microbes into sterile vinegar,the conclusions are obtained as follows:when the adding number of Bacillus cohn and Gluconobacter asia is below 10 cfu/mL,both vinegar could keep clarification for about 40 days;when the adding number of Bacillus cohn and Gluconobacter asia is 105 cfu/mL,the samples could keep clarification only for 2 days and 8 days and the dry weight of precipitate is 0.942,0.753 g/dL respectively.It is easier for Bacillus cohn than Gluconobacter asia to cause vinegar turbidity,and large number of Bacillus cohn makes the vinegar smelly.When 1 g/kg sodium benzoate is added into vinegar with 105 cfu/mL Bacillus cohn and 105 cfu/mL Gluconobacter asia respectively,the clarification period of vinegar could prolong for 7 days and 4 days.