椰子油基酸奶的品质及体外消化特性研究Quality and in vitro digestive properties of coconut oil-based yogurt

为开发新型酸奶，给消费者提供更多的选择，以脱脂奶粉、水、椰子油为原料，经高速剪切、高压均质制备富含椰子油的复原乳，再经灭菌、冷却、接种、发酵后制得椰子油基酸奶。探究了椰子油添加量（0%、2%、4%、6%、8%、10%和12%）对复原乳粒径的影响，对酸奶酸度、色度、持水性、感官特性、质构特性的影响，并研究了感官得分最高的椰子油基酸奶的消化特性。结果表明：椰子油添加量在2%～8%时，复原乳的平均粒径和粒径分布均无显著性差异；椰子油添加量为6%时，酸奶感官评分最高，为89.1分，此时酸奶的持水力为87.1%、pH为4.25、色度L*为89.42；体外肠消化模拟实验证明，椰子油基酸奶（椰子油添加量为6%）的甘油三酯水解率及脂肪酸释放率分别比相同含油量的传统酸奶高25.99%及13.85%。综上，添加椰子油有利于酸奶的消化吸收，且椰子油添加量为6%时制得的酸奶整体品质最好。In order to develop a new type of yogurt and provide consumers with more choices, reconstituted milk rich in coconut oil was prepared by high-speed shearing and high-pressure homogenization with skim milk powder, water and coconut oil as raw materials, and then coconut oil-based yogurt was obtained after the sterilization, cooling, inoculation and fermentation of the reconstituted milk. The effect of coconut oil amount (0%, 2%, 4%, 6%, 8%, 10% and 12%) on the particle size of reconstituted milk was explored. Furthermore, the effects of coconut oil amount on the acidity, color, water holding capacity, sensory properties and texture properties of yogurt were investigated. The digestive properties of the coconut oil-based yogurt with the highest sensory scores were also explored. The results showed that when the amount of coconut oil was added at 2%-8%, there was no significant difference in the average particle size and particle size distribution of reconstituted milk. Moreover, the sensory score of the yogurt showed the best performance (with score of 89.1) when the oil amount was 6%. The water holding capacity of the yogurt with best performance was 87.1%, the pH was 4.25, and the brightness L* was 89.42. In vitro intestinal digestion showed that the triglyceride hydrolysis rate and fatty acid release rate of coconut oil-based yogurt (coconut oil amount 6%) were 25.99% and 13.85% higher than those of traditional yogurt with the same oil content, respectively. Overall, the addition of coconut oil facilitates the digestion and absorption of the yogurt and the overall quality of the yogurt is the best when the coconut oil amount is 6%.