益生乳酸菌的生理特性研究及其在发酵果蔬饮料中的应用

作为世界上最大的水果蔬菜生产国家之一,中国的水果蔬菜资源非常丰富,但其鲜销状况却不容乐观。此外,随着生活水平的提高和健康意识的增强,人们逐渐接受益生乳酸菌发酵技术开发的新型发酵果蔬饮料,这主导了果蔬饮料发展的方向。研究评价了不同种属乳酸菌的耐酸性和耐胆盐能力,得到5株能较好适应人体胃肠环境的菌株,并应用于复合果蔬汁的快速发酵。通过感官评定,确定了混合果蔬汁的优化比例。通过正交设计试验,优化发酵条件并进行单菌发酵和混合菌种发酵。实验结果表明,5株乳酸菌发酵产物的pH值均有大幅下降,酸度增加；发酵果蔬汁储藏第1周出现酸的转化；混合菌株发酵产品的酸度几乎是单一菌株发酵产品的2倍,酸的转化发生在冷藏第2周。

Research of Beneficial Lactic Acid Bacteria and Its Application for Fermented Fruit and Vegetable Juices

China is one of the largest fruit and vegetable producing countries in the world, but the current situation of fresh sales is severe. Since the increasing of people''s living standards and the health awareness, the probiotic lactic acid bacteria fermentation technology has been applied in developing new fermented fruit and vegetable drinks. It has become the main direction of the current fruit and vegetable drinks producing. The experiment researches the ways of screening the probiotic lactic acid bacteria and the processing technology of composite fruit and vegetable juice fermented beverage, main contents and conclusions are as follows. By evaluating the ability of bile and acid resistance of different species of lactic acid bacteria, 5 species which can better adapt to the human gastrointestinal environment have been screened and applied to the rapid fermentation of a mixed drink. The combination of mixed juice was determined through the sensory evaluation. Through orthogonal test, the optimum fermentation conditions were decided. The monoxenie fermentation was conducted under the optimal fermentation conditions. Test results showed that the pH of five kinds lactic acid bacteria fermentation products have reduced significantly while the acidity increased. The acid conversion in fermented juice took place after one week storage. The results of mixed strain fermentation showed that the acidity of the mixed fermentation product was almost as twice as the monoxenie fermentation products, acid conversion occurred after two weeks in a refrigerator.