为开发高活性玉木耳多糖酸奶,以玉木耳多糖(Auricularia cornea var. Li polysaccharides,ACP)为原料,测定其基本组分与流变特性,并通过单因素实验及正交试验优化了ACP酸奶生产工艺,探究了ACP对酸奶品质的影响。结果表明:ACP总糖、糖醛...为开发高活性玉木耳多糖酸奶,以玉木耳多糖(Auricularia cornea var. Li polysaccharides,ACP)为原料,测定其基本组分与流变特性,并通过单因素实验及正交试验优化了ACP酸奶生产工艺,探究了ACP对酸奶品质的影响。结果表明:ACP总糖、糖醛酸、蛋白质含量分别为82.21%±2.40%,11.95%±1.28%,2.36%±0.10%。流变特性显示玉木耳多糖溶液既表现出液体的特征,也表现出固体的特征,具有良好的粘弹性,有作为增稠剂和凝胶剂的潜在应用价值。ACP能促进酸奶发酵,使乳酸菌活菌数增加,酸度上升,p H降低;ACP浓度范围为0.02%~0.08%可提高酸奶持水力,改善酸奶组织状态和稳定性,减少乳清析出;ACP添加量为0.04%时,酸奶持水力、硬度、稠度、粘聚性和粘度最大,感官品质最好,ACP添加量为0.06%时,酸奶乳酸菌活菌数最多,酸度最高。玉木耳多糖酸奶最佳生产工艺为添加鲜奶量的0.04%ACP、6%蔗糖、0.1%发酵剂,于42℃发酵7 h,于4℃冷藏24 h,制作的酸奶较普通酸奶具有更高的活菌数及更好感官品质和质构特性。本实验通过探索玉木耳多糖对乳酸菌发酵和酸奶品质的影响,以期为改善酸奶保健性能和品质,拓宽玉木耳多糖的应用范围提供科学理论依据。展开更多
In the present investigation, the sensitivity of different direct microbial count procedures applied on systems containing both planktonics and sessiles was tested. The direct count pour plate was compared with direct...In the present investigation, the sensitivity of different direct microbial count procedures applied on systems containing both planktonics and sessiles was tested. The direct count pour plate was compared with direct epifluorescent microscopic enumerations in order to evaluate the efficiency of the studied techniques in giving information about microbial activity or viability. Our results indicate that the standard plate count procedure is the most sensitive method to estimate viable and cultivable planktonic cells. On the other hand, direct enumeration by epifluorescent microscopy may become an interesting alternative to count sessile cells.展开更多
文摘为开发高活性玉木耳多糖酸奶,以玉木耳多糖(Auricularia cornea var. Li polysaccharides,ACP)为原料,测定其基本组分与流变特性,并通过单因素实验及正交试验优化了ACP酸奶生产工艺,探究了ACP对酸奶品质的影响。结果表明:ACP总糖、糖醛酸、蛋白质含量分别为82.21%±2.40%,11.95%±1.28%,2.36%±0.10%。流变特性显示玉木耳多糖溶液既表现出液体的特征,也表现出固体的特征,具有良好的粘弹性,有作为增稠剂和凝胶剂的潜在应用价值。ACP能促进酸奶发酵,使乳酸菌活菌数增加,酸度上升,p H降低;ACP浓度范围为0.02%~0.08%可提高酸奶持水力,改善酸奶组织状态和稳定性,减少乳清析出;ACP添加量为0.04%时,酸奶持水力、硬度、稠度、粘聚性和粘度最大,感官品质最好,ACP添加量为0.06%时,酸奶乳酸菌活菌数最多,酸度最高。玉木耳多糖酸奶最佳生产工艺为添加鲜奶量的0.04%ACP、6%蔗糖、0.1%发酵剂,于42℃发酵7 h,于4℃冷藏24 h,制作的酸奶较普通酸奶具有更高的活菌数及更好感官品质和质构特性。本实验通过探索玉木耳多糖对乳酸菌发酵和酸奶品质的影响,以期为改善酸奶保健性能和品质,拓宽玉木耳多糖的应用范围提供科学理论依据。
文摘In the present investigation, the sensitivity of different direct microbial count procedures applied on systems containing both planktonics and sessiles was tested. The direct count pour plate was compared with direct epifluorescent microscopic enumerations in order to evaluate the efficiency of the studied techniques in giving information about microbial activity or viability. Our results indicate that the standard plate count procedure is the most sensitive method to estimate viable and cultivable planktonic cells. On the other hand, direct enumeration by epifluorescent microscopy may become an interesting alternative to count sessile cells.