【作者】 王芳平； 吴逗逗； 闻浩翔； 曹雪慧； 朱丹实；

【Author】 Wang Fangping;Wu Doudou;Weng Haoxiang;Cao Xuehui;Zhu Danshi;College of Food Science and Technology,Bohai University;

【机构】 渤海大学食品科学与工程学院；

【摘要】 国光苹果是我国辽西地区的特色品种,口味较好,但果皮较厚,鲜食品质略差,可通过加工方式进一步提高产品附加值。本研究以国光苹果为原材料制备苹果浊汁(cloudy apple juice,CAJ),探究自然发酵(natural fermentation,NF)与接种发酵(inoculation fermentation,INF)对发酵苹果浊汁理化特性及风味的影响。CAJ经巴氏杀菌后,接入1.5 g/L发酵剂(Lactobacillus bulgaricus:Streptococcus thermophilus=1:1)与未杀菌的自然发酵果汁对照研究。两组果汁均添加6%蔗糖,置于35℃恒温箱中发酵15 d。结果表明,在整个发酵过程中,两组大多数理化指标变化趋势相似,但自然发酵组变化速率较接种发酵组快。自然发酵组和接种发酵组果汁的pH分别从3.90左右分别降至3.50和3.29;巴氏杀菌后果汁浊度(NTU)从1442.70降至1145.00,经发酵后接种发酵组浊度下降较快,发酵末期降至778.67,远低于自然发酵组的880.6。发酵末期,电子鼻分析表明,自然发酵组的挥发性气味比接种发酵组强烈,但通过感官评价其滋味接受度较低。总体来看,利用Lactobacillus和Streptococcus thermophilus发酵后的国光果汁浊度较低,挥发性风味略差,但口味比自然发酵好。对本研究可为国光苹果加工及发酵果汁产品的开发提供理论参考。更多还原

【Abstract】 Ralls apple is a typical variety in the western Liaoning region of China.The taste of Ralls apple is better,but the skin is thicker,so the fresh quality is slightly less.It can be processed to increase the added value of the product.In this research,Ralls apple was used as raw material to prepare cloudy apple juice(CAJ),and the effects of the natural fermentation(NF) and the inoculation fermentation(INF) on the physicochemical properties and flavor of fermented cloudy apple juice(FCAJ) were investigated.After pasteurization of CAJ,1.5 g/L starter(Lactobacillus bulgaricus:Streptococcus thermophilus=1:1) was added to compared with unsterilized natural fermented juice.The juice of both groups were added with 6% sucrose and fermented at 35℃ for 15 days.The results showed that,during the whole fermentation process,the change trend of most physical and chemical indexes was similar between the two groups,but the change rate of the NF group was faster than that of the INF group.At the beginning of fermentation(0-3 d),the contents of ascorbic acid and soluble protein of CAJ in the INF group were significantly lower than those in the NF group.The pH of CAJ in the NF group and the INF group decreased from about 3.90 to 3.50 and 3.29,respectively.After pasteurization,the turbidity of CAJ decreased from 1442.7 NTU to 1145.0 NTU,and the INF group’s turbidity decreased rapidly to 778.67 at the end of fermentation,which was much lower than that of the NF group(880.6 NFT).At the end of fermentation,electronic nose analysis showed that the volatile odor of the NF group was stronger than that of the INF group,but its taste acceptance was lower by sensory evaluation.In general,the Ralls apple juice fermented with Lactobacillus Bulgaricus and Streptococcus Thermophilus has lower turbidity and slightly poor volatile flavor,but the taste is better than that of natural fermentation.This study can provide theoretical reference for Ralls apple processing and the development of fermented fruit juice products.更多还原