酵母发酵黄鰤鱼鱼卵的工艺探究及其风味成分分析

Process Optimization and Flavor Composition Analysis of Seriola lalandi Roe by Yeast Fermentation

为了探究酵母发酵对黄鰤鱼鱼卵脱腥增香的影响,本文先研究了黄鰤鱼鱼卵营养价值,后采用高糖型高活性干酵母对其进行发酵脱腥处理,以感官评分、pH和总酸含量为指标,确定酵母粉接种量、蔗糖添加量、发酵时间和发酵温度等发酵参数。以新鲜鱼卵和未发酵鱼卵作对照,分析发酵后鱼卵样品感官品质、游离氨基酸和挥发性风味化合物的变化。结果表明,黄鰤鱼鱼卵富含多不饱和脂肪酸及锌和硒元素,营养价值较高。在酵母接种量为1.5%,蔗糖添加量为5%,发酵时间为1.5 h,发酵温度为28℃时,黄鰤鱼鱼卵的鱼腥味最低、发酵香味最浓郁、整体风味协调性最好。黄鰤鱼鱼卵中甜味和鲜味氨基酸的含量显著上升(P<0.05),且TAV值总和大于苦味氨基酸,表明酵母发酵掩盖了鱼卵本身的苦味。三种鱼卵样品中共检出81种挥发性化合物,经酵母发酵后,鱼卵中挥发性化合物种类和含量均增加。新鲜鱼卵和未发酵鱼卵中的主要挥发性化合物是庚醛、壬醛、(E,E)-2,4-庚二烯醛等醛类物质,并且腥味物质(1-辛烯-3-醇、(E,E)-2,4-庚二烯醛等)的相对含量较高。酵母发酵鱼卵的主要挥发性化合物是辛酸乙酯和癸酸乙酯等酯类物质,而腥味物质相对含量显著降低(P<0.05)。根据相对气味活度值(relative odor activity values,ROAV值),酵母发酵鱼卵中的关键性风味物质为(E,Z)-2,6-壬二烯醛、(E,E)-2,4-癸二烯醛、苯乙醇、1-辛烯-3-醇和3-甲硫基丙醇,代表鱼腥味的关键性风味物质1-辛烯-3-醇的ROAV值明显下降,新增苯乙醇和3-甲硫基丙醇两种风味成分,为发酵鱼卵提供了玫瑰香味、甜味和肉香味等。总之,酵母发酵有效改善了黄鰤鱼鱼卵的异味,并产生了怡人的发酵风味。

To explore the effects of yeast fermentation on deodorization and flavor enhancement of Seriola lalandi roe,the nutritional value of Seriola lalandi roe were studied in this paper at first,and then high sugar type instant dry yeast was selected as the fermenting agent,the optimal fermentation process conditions were optimized by single-factor experimental analysis according to the sensory score,pH and total acid content.Fresh fish roe and unfermented fish roe were used as controls to analyze the difference in sensory quality,free amino acids and volatile flavor composition of the fermented fish roe.The results showed that,the Seriola lalandi roe was rich in polyunsaturated fatty acids,zinc and selenium elements,and had high nutritional value.The best deodorization effect by 1.5% yeast inoculum,5% sucrose addition,1.5 h fermentation time and 28℃ fermentation temperature.The contents of sweet amino acids and umami amino acids in fermented roe increased significantly(P<0.05),and the sum of TAV values was greater than that of bitter amino acids,indicating that the bitter taste of the fish roe was masked after yeast fermentation.A total of 81 volatile compounds were detected in the three fish roe samples,and the types and contents of volatile compounds in fish roe increased after yeast fermentation.The main volatile compounds in fresh and unfermented fish roe were aldehydes such as heptanal,nonanal and(E,E)-2,4-heptadiena.1-octen-3-ol and(E,E)-2,4-heptadiena with fishy smell were higher relative contents.Yeast fermented fish roe were rich in esters such as ethyl octanoate and ethyl decanoate,while the relative content of fishy substances was significantly lower(P<0.05).According to the relative odor activity values(ROAV),the flavor active components of yeast fermented fish roe were(E,Z)-2,6-nonadienal,(E,E)-2,4-decadienal,phenylethanol,1-octen-3-ol and 3-methylthiopropanol,and the ROAV of 1-octen-3-ol producing fishy odor decreased significantly.After fermentation,phenylethanol and 3-methylthiopropanol were added as the key flavor compounds,which provided the rose flower,sweet and meat aroma.In summary,yeast fermentation played a role in eliminating fishy smell and produced pleasant aromatic flavor.