银耳多糖对椰浆酸奶感官品质及益生菌生长的影响

Effect of Tremella fuciformis Polysaccharides on Sensory Quality and Probiotic Growth of Coconut Milk Yogurt

银耳多糖是银耳中重要的天然多功能活性成分,保加利亚乳杆菌和嗜热链球菌则是用于酸奶发酵最常见的益生菌。为了探究银耳多糖对保加利亚乳杆菌和嗜热链球菌生长的影响,本研究测定添加不同浓度银耳多糖的MRS液体培养基中保加利亚乳杆菌和嗜热链球菌的OD_(600),绘制生长曲线,并对MRS固体培养基上两种菌的活菌数进行计数。为扩大银耳多糖应用范围,使用保加利亚乳杆菌和嗜热链球菌对含有不同浓度银耳多糖的椰浆进行发酵,对发酵所得的椰浆制品进行感官评价并测定活菌数。研究结果显示,银耳多糖浓度越高,保加利亚乳杆菌和嗜热链球菌的OD_(600)越大,活菌数量也逐渐增多。在对数生长期内,培养基中银耳多糖的浓度越高,保加利亚乳杆菌和嗜热链球菌的生长速度越快。以上结果说明银耳多糖可以有效促进保加利亚乳杆菌和嗜热链球菌的增殖。当添加的银耳多糖浓度为8 g/100 mL时,发酵椰浆制品中的活菌数为1.28×10^(7)CFU·mL^(-1),产品此时的感官评分最高,品质最好。

Tremella fuciformis polysaccharide(TFP)is an important,natural and multifunctional active ingredient in Tremella fuciformis,while Lactobacillus bulgaricus and Streptococcus thermophilus are the most common probiotics used in yogurt fermentation.In order to explore the effects of TFP on the growth of L.bulgaricus and S.thermophilus,the OD_(600)of L.bulgaricus and S.thermophilus was measured,followed by drawing the growth curve of both probiotics,and the viable count of L.bulgaricus and S.thermophilus was also measured,which were cultured on MRS media with different concentrations of TFP.In order to expand the application range of TFP,L.bulgaricus and S.thermophilus were used to ferment the coconut milk with different concentrations of TFP,and the sensory evaluation was performed on the fermented coconut milk,and the viable count of L.bulgaricus and S.thermophilus in it was also determined.The results of the study showed that the OD_(600)of L.bulgaricus and S.thermophilus cultured in MRS liquid and on MRS solid medium increased with the higher concentration of TFP added.In the logarithmic growth period,with the increasing of the concentration of TFP,the growth rate of L.bulgaricus and S.thermophilus was faster.The results showed that TFP could effectively promote the growth of L.bulgaricus and S.thermophilus.When the concentration of TFP was 8 g/100 mL,the number of viable bacteria in fermented coconut milk yogurt was 1.28×10^(7)CFU·mL^(-1),and the sensory score and quality of the product were the highest at this time.