云南建水酸浆豆腐中乳酸菌的生长特性

Study on growth characteristics of lactic acid bacteria from the acid slurry bean curd of Yunnan Jianshui

为了筛选出优良的乳酸菌进行发酵制作酸浆,对分离自云南建水豆腐酸浆中的五株乳酸菌(SYG01、SYG02、SYG03、SYG04、SYG05)的生长曲线、产酸能力、耐酸能力和耐渗透压能力进行了比较。生长曲线实验表明在相同培养时间内,菌株SYG02繁殖能力最强,其次是菌株SYG03,而菌株SYG05、SYG04、SYG01的生长速率明显较慢;在产酸方面SYG02产酸能力最强,速度最快,SYG03、SYG05和SYG04次之,SYG01最弱。在耐酸方面,在p H4.0的环境下5株菌生长良好,在p H3.0的酸性环境下5株菌虽然能够存活,但活菌数的数量级仅在10~2~10~4CFU/m L,其中菌株SYG02和SYG03比其它三株菌株表现出较好的耐酸能力。在耐渗透压方面,SYG02在8%(w/V)的Na Cl中依然表现出较强的耐受性,活菌数的数量级达到10~7CFU/m L,其余4株菌在Na Cl含量大于6%(w/V)时生长受到明显抑制。并以发酵黄浆水的p H及产酸量为指标对菌株的产酸能力进行比较,发现混合菌株的产酸能力高于单菌株,其中菌株SYG02和菌株SYG03组合发酵的效果最好,在发酵72 h后黄浆水的p H为3.52,产酸量达到6.46 g/L。从而得出菌株SYG02具有良好的生长、产酸和耐渗透压能力,具有良好的应用潜力,对酸浆豆腐的工业化生产有重要的意义。

To screen the suitable lactic acid bacteria fermentation acid whey,the growth curve,acid production,acid tolerance and osmotic pressure tolerance ability of five lactic acid bacteria which isolated from tofu acid whey of Yunnan Jianshui acid slurry bean curd were compared.The results of growth curve experiment showed that the strain SYG02 had the strongest reproductive capacity,followed by the strain SYG03,and the growth rates of strains SYG05,SYG04,SYG01 were significantly slower.SYG02 produced the most acid within the least time,followed by SYG03,SYG05 and SYG04,and SYG01 was the weakest.All of the five strains could well-grown at the condition of p H4.0,and could survive at the condition of p H3.0,while the total plant counts were only 10~2~10~4CFU/m L,SYG02 and SYG03 showed better acid resistance than other three strains.In terms of osmotic tolerance,SYG02 showed strong tolerance to 8%（w/V）Na Cl,the growth of the other 4 strains was inhibited obviously when the content of Na Cl was more than 6%（w/V）.A conclusion was drawn from the comparison of the p H and acid production of the fermentation tofu whey that the acid producing ability of mixed strains was better than single strain that the acid producing ability of mixed strains was better than single strain,the strain SYG02 and SYG03 had the best effect on fermentation tofu whey,after 72 h fermentation tofu whey p H was 3.52,acid production reached 6.46 g/L.Accordingly,SYG02has good abilities of producing acid and resisting osmotic pressure,the strain have a good application potential and can play an important role for the commercial process of acid slurry bean curd.