微生物发酵制备富含共轭亚油酸酸豆乳的研究

Study on Preparation of Acid Soymilk Rich in Conjugated Linoleic Acid by Microbial Fermentation

将乳酸菌发酵应用于豆浆产品深加工,将豆浆中亚油酸转化成共轭亚油酸。首先探讨豆浆生产的最佳工艺,通过单因素和正交试验确定最佳工艺为:泡豆15 h、水豆比例10∶1(mL/g)、加热沸腾时间8 min,在此条件下,豆浆中蛋白质含量为3.96%。其次,将植物乳杆菌接种在不同比例组成的豆浆和牛奶复配培养基中驯化,并且观察生长特性,在豆浆含量80%时不仅菌种生长较好且能提高豆浆营养价值。最后对产共轭亚油酸培养条件进行优化,通过单因素和正交试验确定产共轭亚油酸的最佳发酵条件是:蔗糖添加量6%、琼脂添加量0.7%、接种量4%、培养时间30 h,其共轭亚油酸产量为29.83μg/mL。

b Lactic acid bacteria fermentation was applied to deep processing of soymilk products. It can convert the linoleic acid of soymilk to conjugate linoleic acid. First of all, optimum technology of soymilk production was discussed. Through the single and orthogonal test, the conditions were optimized as follows： soak beans 15 h, weight rations of water and beans 10 ∶ 1 （mL/g ）, boiling time 8 min. On this condition, the protein content in soymilk was 3.96 %. Secondly, putting Lactobacillus planticola into different proportions of soymilk and milk medium to domesticate and observed growth characteristics. It not only grew better when the soymilk content was 80 %, but also increased the nutritional value of soybean milk. At last, through the single and orthogonal test, the fermentation conditions were optimized as follows： sucrose content 6 %, agar content 0.7 %, inoculation amount 4 % and incubation time 30 h. Its conjugate linoleic acid output was 29.83 μg/mL.