双菌协同发酵苹果醋研究及其品质分析

以苹果为原材料，利用巴氏醋杆菌（Acetobacter pasteurianus）和植物乳杆菌（Lactobacillus plantarum）进行双菌协同发酵生产苹果醋。采用单因素和响应面试验优化发酵工艺条件，并与巴氏醋杆菌发酵苹果醋的主要理化指标及风味物质进行对比。结果表明，双菌协同发酵苹果醋最佳工艺条件为初始酒精度9%vol、发酵温度31 ℃、巴氏醋杆菌与植物乳杆菌接种量均为10%（V/V）、转速170 r/min，发酵时间12 d。此优化发酵工艺条件下，苹果醋总酸为56.13 g/L。与单菌发酵苹果醋相比，双菌协同发酵苹果醋总多酚、总黄酮、维生素C、游离氨基酸质量浓度显著增多（P＜0.05），抗氧化性明显增强。在单菌和双菌协同发酵苹果醋中分别检测到25种和36种挥发性化合物，双菌协同发酵苹果醋具有更多的酮类和酯类化合物，表现出更好的风味。

Research and quality analysis of apple vinegar by dual-species cooperative fermentation technology

Using apple as raw material, apple vinegar was produced by dual-species cooperative fermentation of Acetobacter pasteuris and Lactobacillus plantarum. The fermentation conditions were optimized by single factor tests and response surface tests, and the main physicochemical indexes and flavor compounds of apple vinegar fermented by A. pasteuris were compared. The results showed that the optimal conditions of apple vinegar by dual-species bacteria cooperative fermentation were as follows: initial alcohol content 9%vol, fermentation temperature 31 ℃, A. pasteurianus and L. plantarum inoculum 10% (V/V), rotation speed 170 r/min, time 12 d. Under these optimal conditions, the total acid of apple vinegar was 56.13 g/L. Compared with apple vinegar by mono-species fermentation, the mass concentrations of total polyphenols, total flavonoids, vitamin C and free amino acids of apple vinegar by dual- species cooperative fermentation significantly increased (P＜0.05), and the antioxidant activity was significantly enhanced. 25 volatile compounds and 36 volatile compounds were detected in the apple vinegar produced by mono-species fermentation and dual-species cooperative fermentation, respectively. The apple vinegar produced by dual-species cooperative fermentation had more ketones and esters, and showed better flavor.