功能低聚糖对植物乳杆菌ZDY2013发酵乳发酵特性及冷藏效果的影响

为探究功能低聚糖对植物乳杆菌ZDY2013发酵乳的发酵特点和冷藏期功能的影响，选取具有益生元特性的低聚木糖、低聚异麦芽糖及其组合物为发酵乳中碳水化合物，评价发酵乳中植物乳杆菌发酵特性和pH值变化，同时对发酵乳的持水性及冷藏期抗氧化活性进行解析。结果表明：植物乳杆菌能利用不同浓度功能低聚糖进行代谢；相比葡萄糖，发酵乳中添加低聚糖更有利于植物乳杆菌的生长，尤其是其组合物浓度为3.0%时，能显著提高发酵乳中活菌数及降低发酵乳pH值；冷藏期（21 d）内，各组发酵乳活菌数呈下降趋势，但均高于108 cfu/g，pH值在7 d后比较稳定，而持水性不断增强；发酵乳DPPH自由基清除能力在第7 d最强，而ABTS+和羟自由基的清除能力呈下降趋势，且添加同浓度的组合物优于葡萄糖。该研究结果将为功能低聚糖及植物乳杆菌ZDY2013在乳品开发中的应用提供理论依据。

Effects of Functional Oligosaccharides on Fermentation Characteristics and Cold Storage of Fermented Milk Using Lactobacillus plantarum ZDY2013

To investigate the effects of functional oligosaccharides on the fermentation characteristics and cold storage of milk fermented using Lactobacillus plantarum (L. plantarum) ZDY2013, the fermentation characteristics and pH variations of L. plantarum in the fermented milk were evaluated upon adding different prebiotic carbohydrates, namely xylo-oligosaccharides, isomaltose oligosaccharides, and their composites, into the fermented milk. At the same time, the water holding capacity and antioxidant activity of the fermented milk during cold storage were analyzed. The results revealed that L. plantarumcan be metabolized with different functional oligosaccharides at different concentrations. Compared with glucose, oligosaccharides added to the fermented milk were found to be more beneficial for the growth of L. plantarum. More specifically, at the composite concentration of 3.0%, the number of viable bacteria in the fermented milk increased significantly, while the pH of the fermented milk reduced. During 21 days of cold storage, the number of viable bacteria in each experimental group reduced, but it was higher than 108 cfu/g. Meanwhile, the pH was relatively stable after 7 days of cold storage, and the water holding capacity increased continually. All the experimental groups exhibited the strongest DPPH radical scavenging abilities on day 7, while the ABTS and hydroxyl radical scavenging abilities are declined. Additionally, at the same concentration, the addition of oligosaccharide composites outperformed that of glucose. The results of this study will provide a theoretical basis for the application of functional oligosaccharides and L. plantarum ZDY2013 in the development of dairy products.