Abstract: In order to improve the flavor and quality of goat milk yogurt and enhance its functional value, Lactobacillus plantarum JS5 and JS19, isolated from Jiangshui, a traditional Chinese fermented vegetable food, were used for goat milk fermentation. The physicochemical properties, textural characteristics, and functional properties of goat milk yogurt were evaluated. The results showed that mixed-culture fermentations with each isolate and a commercial starter culture improved the water-holding capacity and apparent viscosity of goat milk yogurt, reduced its hardness and gumminess and promoted the release of acetaldehyde and diacetyl. The rate of cholesterol degradation (up to 36.62%) in goat milk yogurt containing Lactobacillus plantarum JS5 was significantly higher than that in the control group (P < 0.05). Goat milk yogurt containing Lactobacillus plantarum JS19 showed stronger antioxidant capacity in vitro, which could scavenge 70.58% of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and had a ferric ion reducing antioxidant power (FRAP) value of 32.03 μmol ferrous sulfate equivalent/L on the first day of storage. Therefore, both strains are suitable for goat milk fermentation.

Key words: Lactobacillus plantarum; goat milk yogurt; quality; flavor; functional properties

摘要： 为改善酸羊乳风味与品质，提高酸羊乳的功能价值，将自浆水中筛选的植物乳杆菌JS5和JS19用于羊乳发酵，研究其对酸羊乳理化性质、质构特性及功能特性的影响。结果表明：2 种植物乳杆菌与商业发酵剂复合发酵后，均能在贮藏期内有效提高酸羊乳持水性和表观黏度，降低其硬度与胶着性，促进乙醛和双乙酰的释放；添加植物乳杆菌JS5的酸羊乳胆固醇降解率显著高于对照组（P＜0.05），最高可达36.62%；添加植物乳杆菌JS19的酸羊乳体外抗氧化能力更强，贮藏1 d时1,1-二苯基-2-三硝基苯肼自由基清除率高达70.58%，铁离子还原/抗氧化能力达32.03 μmol/L。2 种菌株均为适用于羊乳发酵生产的优良菌株。

关键词: 植物乳杆菌；酸羊乳；品质；风味；功能特性