发酵型海带-苹果复合果汁饮料的研制及发酵体系抗氧化活性的研究

本课题以海带汁、苹果汁、白砂糖为主要原料，以植物乳杆菌作为发酵菌种，研制了一款风味优良、天然营养的发酵型海带复合果汁饮料。以感官评分为标准，通过单因素实验和正交试验设计对复合果汁饮料进行了工艺优化。得到该复合果汁饮料的最佳配方参数为:海带汁-苹果汁复配体积比为1:2、白砂糖添加量为3%、植物乳杆菌接种量为8%、发酵时间24 h、发酵温度32 ℃。体外抗氧化活性试验结果表明，本课题研制的发酵型海带复合果汁饮料对DPPH自由基抑制率为73.20%，对ABTS+自由基抑制率为36.05%，总抗氧化能力为0.774。整体来看，海带汁和苹果汁均具有一定的抗氧化能力，发酵使得海带汁的抗氧化能力提高，但会使得苹果汁的抗氧化能力降低。但是单纯的海带汁发酵，其口感风味较差，苹果汁的添加以及发酵产生的乳酸在一定程度上掩盖海带的腥味。另一方面，海带汁的加入能弥补单独苹果汁发酵抗氧化能力的下降，复合发酵对饮料DPPH自由基清除力具有明显提高作用。本研究解决了海带饮料腥味过重的问题，探索了海带苹果复合果汁饮料发酵体系的抗氧化活性，为海带复合果汁饮料的开发提供理论依据和实践指导。

Fermentation Optimization of Kelp-Apple Compound Juice Beverage and the Antioxidant Activity of Its Fermentation System

In this study,kelp juice,apple juice and sugar were used as the main raw materials,and Lactobacillus plantarum was applied as the fermentation strain,to develop a fermented kelp-apple compound juice beverage with excellent flavor and natural nutrition.Based on sensory scores,the process optimization of the compound fruit juice beverage was carried out through single factor experiments and orthogonal experiment design.The best formula and fermentation condition of the beverage were as follows:1:2 volume ratio of kelp juice to apple juice,3%sucrose addition,8%Lactobacillus plantarum inoculation,fermentation time 24 hours and temperature 32℃.The result of antioxidant activity assay showed that the inhibition rate of DPPH free radical,ABTS+free radical and total antioxidant capacity of fermented kelp-apple juice beverage were 73.20%,36.05%and 0.774,respectively.On the whole,both kelp juice and apple juice showed certain antioxidant capacity.Fermentation improved the antioxidant capacity of kelp juice,but reduced the antioxidant capacity of apple juice.However,the fermentation of sole kelp juice had poor taste and flavor.The addition of apple juice and lactic acid produced by fermentation masked the fishy smell of kelp to a certain extent.On the other hand,the addition of kelp juice prevented decline of antioxidant capacity of sole apple juice fermentation.Fermentation of two juices could significantly improve the DPPH free radical scavenging capacity of beverage.This study solved the problem of fishy smell of kelp beverage,explored the antioxidant activity of kelp-apple juice beverage fermentation system,and would provide theoretical basis and practical guidance for the development of kelp-fruit juice beverage.