凝固型葡萄酸奶的工艺研究

Research on Production Technology of Solidifying Grape Yoghurt

以鲜牛乳和新鲜葡萄汁为主要原料,添加白砂糖、抗坏血酸,采用保加利亚乳杆菌和嗜热链球菌为发酵剂,以感官、理化、微生物检测为评定指标,研究开发凝固型葡萄酸奶.通过单因素试验和L9(34)正交试验,对葡萄酸奶的主要工艺参数、配方及发酵条件进行筛选,确定最佳工艺条件.结果表明,最佳工艺配方为:蔗糖添加量6%,灭菌时间30min,葡萄汁添加量15%,Vc抗褐变浓度为5%,发酵剂接种量4%,发酵时间4.5h.根据以上配方生产出来的凝固型葡萄酸奶色泽均匀,酸甜适宜,质地细腻,营养丰富,具有葡萄特有的风味,乳香气浓郁清爽,口感香醇.

Production technology of solidifying grape yoghurt was studied,using fresh milk and fresh grape juice as main raw material,adding white granulated sugar and ascorbic acid,adopting Lactobacillus bulgaricus and Streptococcus thermophilus as fermenting agent,sensory detection,physical and chemical detection,microbiological detection as the evaluating index. Main process parameter,formula and fermenting conditions was screened by Single factor test and L9（ 34） orthogonal test. Results showed that,the best process formula was,sugar content 6%,sterilization time 30 mins,grape juice content 15%,ascorbic acid content 5%,fermenting agent content 4%,fermenting time 4. 5hr. The grape yoghurt produced by above formula had uniform color,suitable proportion of sugar and acid,fine texture,rich nutrition,with special flavor of grape,fresh milk aroma and mellow taste.