复配魔芋寡糖/低聚异麦芽糖增殖嗜酸乳杆菌的协同增效研究

魔芋寡糖最近被认定为新食品原料,具有良好的促进益生菌增殖作用,但其生产成本较高,妨碍商业应用。本研究利用成本较低的低聚异麦芽糖与魔芋寡糖进行复配,考察复配低聚糖对嗜酸乳杆菌增殖的综合效果。分别以不同浓度及不同分子量魔芋寡糖、低聚异麦芽糖、不同比率魔芋寡糖/低聚异麦芽糖复合物为碳源,进行嗜酸乳杆菌体外培养实验,采用OD值、菌落总数和p H值来评价嗜酸乳杆菌增殖效果。结果:低分子量魔芋寡糖增殖效果优于中高分子量魔芋寡糖,魔芋寡糖和低聚异麦芽糖最适添加量为2%。与添加单一低聚糖比较,复配低聚糖在1:1比率下,提高对嗜酸乳杆菌的增殖促进作用,且减缓发酵液酸度下降。因此复配寡糖能够有效降低生产成本,并且增强嗜酸乳杆菌增殖效果,更加适用于食品中。

Synergistic Effect of Konjac Oligosaccharides/Isomalto-oligosaccharide Complex on the Growth of Lactobacillus acidophilus

Konjac oligosaccharides (KOS), a new food raw material, can promote probiotics proliferation, but its commercial application is restricted by its high cost. The present study aimed to prepare a complex of KOS and low-cost isomalto-oligosaccharide (IMO) to examine the synergistic effect of the complex on the growth of Lactobacillus acidophilus. Different concentrations and molecular weights of KOS and IMO as well as different ratios of KOS/IMO complexes were used as carbon sources to conduct the in vitro culture experiments of L. acidophilus. The effect on the L. acidophilus proliferation was evaluated by measuring the optical density (OD) value, the total number of colonies, and pH value. The results showed that the proliferative effect of low-molecular-weight KOS was better than those of medium- and high-molecular-weight KOS, and the optimum amounts of KOS and IMO addition were 2%. Compared with the addition of single oligosaccharides, addition of the KOS/IMO complex at a ratio of 1:1 enhanced the proliferation of L. acidophilus and reduced the acidity of the fermentation broth. Therefore, the KOS/IMO complex can effectively reduce the production cost, enhance the proliferation of L. acidophilus, and is more suitable for food production.