冷藏中低聚果糖对发酵乳中微生物的影响

Effect of oligofructose on the microflora of fermented milk during refrigerated storage

对添加低聚果糖的原料奶,使用嗜酸乳杆菌、双歧杆菌和嗜热链球菌作为快速发酵剂进行发酵后,在4℃条件下储存42d。每周对发酵乳进行微生物分析和酸度测试。结果表明,低聚果糖质量浓度在10～50g/L时对嗜酸乳杆菌和嗜热链球菌的存活都没有太大影响。双歧杆菌活菌数下降幅度比嗜酸乳酸杆菌和嗜热链球菌要快。但添加低聚果糖对双歧杆菌的存活起到重要作用。结论是低聚果糖产品对双歧杆菌有益生作用,因此在冷藏发酵乳制品中有助于提高双歧杆菌活菌数。

Oligofructose supplemented and control fermented milk were produced using s starter culture as the source of Lactobacillus acidophilus, bifidobacteria and Streptococcus thermophilus, and were then stored at 4 ℃ for 42 d. Microbiological analysis and acidity measurements were performed weekly. The results showed that the presence of oligofructose at 10～ 50 g/L did not significantly influence the survival of either S.thermophilus or L.acidophilus. The viable counts of bifidobacteria fell more sharply than did those of lactobacilli and streptococci; however, the addition of oligofructose had a significantly beneficial effect on their viability. In conclusion, the oligofructose product tested was found to have prebiotic properties for bifidobacteria, thus, it is suitable for improving the viability of bifidobacteria in refrigerated fermented dairy products.