中文摘要：

实验以脱脂乳为原料,从20株源于新疆传统酸奶的乳酸菌中筛选出3株高产凝乳酶的乳酸菌.以凝乳活性最高的菌株组合为发酵剂,通过单因素及响应面实验,优化鲜奶酪发酵的接种量、发酵时间、后熟时间.结果表明,以植物乳杆菌RC5为发酵剂,其最适发酵工艺为:接种量5%,38℃发酵时间14.5h,4℃后熟时间60min.在该条件下发酵成的鲜奶酪凝乳效果好,色泽均匀,奶味浓郁,口感细腻,为以乳酸菌产凝乳酶代替凝乳酶粉的研究和应用提供基础.

英文摘要：

Three strains of lactic acid bacteria with high activity of rennin were screened from20lactobacillus strains of traditional yoghurt in Xinjiang Province.The optional combination of the3strains with the highest rennin activity was subsequently used to prepare fresh cheese.The effects of inoculum concentration,fermentation time and ripening time on sensory evaluation were detected through single factor experiments and response surface experiment.The results showed that RC5had the best curd effect.The optimal fermentation processes were5%inoculums concentration,14.5h of fermentation at38℃and60min of ripening at4℃.The fresh cheese fermented in this condition had good curd effect,uniform color,rich aroma of milk and delicate taste.This study suggests that rennet originated from lactic acid bacteria instead of rennet powder enabled to produce fresh cheese.