益生菌Lactobacillus helveticus H9在脱脂乳中复配发酵特性研究

Mixed fermentation characteristic of probiotic Lactobacillus helveticus H9 in skim milk

将益生菌Lactobacillus helveticusH9分别与Lactococcus lactis、Streptococcus thermophilus及Lactobacillus delbrueckiisubsp.bulgaricus和Streptococcus thermophilus三类不同的菌种复配发酵脱脂乳,对其复配发酵乳的ACE抑制率、Val-Pro-Pro浓度、Ile-Pro-Pro浓度、游离氨基氮浓度、滴定酸度、p H值、活菌数、黏度、脱水收缩性和凝乳时间进行测定。结果表明,L.helveticusH9与Streptococcus thermophilus IMAU40115,Lactococcus lactis subsp.cremoris IMAU60065,Lactococcus lactissubsp.cremoris IMAU60064,L.delbrueckiisubsp.bulgaricus IMAU20094和Streptococcus thermophilus IMAU40051的复配发酵乳的ACE抑制率大于60%,而且和IMAU40115、IMAU20094和IMAU40051的复配发酵乳具有较高的Val-Pro-Pro和Ile-Pro-Pro浓度。从复配菌种的种类分析发现,Lactococcus lactis较Streptococcus thermophilus和酸奶发酵剂更适宜与L.helveticus H9复配发酵。本文为进一步研究L.helveticus H9发酵乳的开发提供了借鉴。

In our study, probiotic L. helveticus H9 mixed fermentation with Lactococcus lactis, Streptococcus thermophilus, and Yoghurt starters （L. delbrueckii subsp, bulgaricus 和 Streptococcus thermophilus）, respectively, the ACE-inhibitory rate, Val-Pro-Pro concentration, Ile-Pro-Pro con- centration, free amino nitrogen concentration, titratable acidity, pH value, viable counts, viscosity, syneresis and curd time of their mixed fer- mented milk were assessed. Our results indicated that the ACE-inhibitory rates of fermented milk produced by L. helveticus H9 mixed with S. thermophilus IMAU40115, Lactococcus lactis subsp, cremoris IMAU60065, Lactococcus lactis subsp, cremoris IMAU60064, and yoghurt start- er （L. delbrueckii subsp, bulgaricus IMAU20094 and Streptococcus thermophilus IMAU40051） high than 60%. From the perspective of species, group of Lactococcus lactis more suitable for fermentation with L. helveticus H9 than Streptococcus thermophilus and yoghurt starters. Our results provided significant foundation of research for the development of fermented milk produced by L. helveticus H9.