文献类型：期刊文献

中文题名：乳酸菌发酵核桃酸乳不良气味的形成与分析

英文题名：Formation and Analysis of the Off-Flavor of Walnut Yoghurt Fermented by Lactic Acid Bacteria

作者：齐琳[1];王帅[2];苏晨[1];忠梦[1];王冰悦[1];吉洋洋[3];何爱民[3];宋昊[4];荣瑞芬[1]

第一作者：齐琳

机构：[1]北京联合大学生物化学工程学院,生物活性物质与功能食品北京市重点实验室,北京100023;[2]北京市理化分析测试中心,北京100089;[3]河北省(邢台)核桃产业技术研究院,河北临城054300;[4]北京一轻研究院有限公司,北京101111

第一机构：北京联合大学应用文理学院|北京联合大学生物化学工程学院

年份：2022

卷号：43

期号：14

起止页码：234-241

中文期刊名：食品科学

外文期刊名：Food Science

收录：CSTPCD;;EI(收录号：20223412600670);Scopus;北大核心:【北大核心2020】；CSCD:【CSCD2021_2022】；

基金：河北省科技计划项目(18963002D-6);河北省(邢台)核桃产业技术研究院建设项目;2018北京高等学校高水平人才交叉培养“实培计划”项目;核桃产业国家创新联盟(NAWI)资助项目。

语种：中文

中文关键词：乳酸菌;核桃酸乳;挥发性化合物;不良气味;分析

外文关键词：lactic acid bacteria;walnut yogurt;volatile compounds;off-flavor;analysis

摘要：目的:为探究核桃发酵酸乳不良气味物的形成机制及其组成,改善其风味品质。方法:采用对比实验和感官评价分析不同发酵剂、不同原料组分对发酵乳不良气味产生的影响,研究核桃乳发酵过程中原料组分、羰基价与挥发性化合物的变化规律与相关性;采用顶空-固相微萃取-气相色谱-质谱联用技术分析核桃酸乳挥发性化合物组成,采用相对气味活度值和主成分分析法对关键性风味物和不良气味物进行分析。结果:原料中脂肪组分与不良气味产生显著相关,发酵过程中酸乳羰基价与不良气味形成显著相关;核桃酸乳主要的挥发性风味物包括:己酸等3种酸类化合物,乙偶姻等3种酮类物,正己醇等7种醇类化合物,(E)-2-庚烯醛等4种醛类化合物以及丁酸丁酯和其他类化合物;相对气味活度值大于1的挥发物为(E)-2-庚烯醛、乙偶姻、己酸、正己醇、正辛醇、1-庚醇、苯甲醛、2-壬酮、2-庚酮、苯乙烯和苯乙醇;关键风味物为乙偶姻、己酸、(E)-2-庚烯醛、正己醇。结论:己酸、(E)-2-庚烯醛、正己醇、苯甲醛为核桃酸乳不良气味的主要风味物,其形成的主要路径为核桃乳发酵过程脂肪水解产生较多的亚油酸、亚麻酸,在脂肪氧合酶作用下氧化,裂解产生C_(6)~C_(9)的醇、醛、酸类物。
Objective:This study aimed to explore the formation mechanism and composition of unpleasant odorants in fermented walnut yogurt in order to improve its flavor quality.Methods:Comparative experiments and sensory evaluation were used to analyze the effects of different starter cultures and raw materials on the formation of the off-flavor of fermented milk,and the changes in the characteristic odor value of fermented walnut milk as well as acidity,organic acid,protein and fat contents,carbonyl value and the profile of volatile compounds were investigated during walnut milk fermentation,together with the correlation between them.The composition of volatile compounds in walnut yogurt was analyzed by headspace solid phase microextraction combined with gas chromatography-mass spectrometry(HS-SPME-GC-MS),and the key flavor compounds and unpleasant odorants were analyzed by calculating their relative odor activity values(ROAV)as well as using principal component analysis(PCA).Results:The fat content and the carbonyl value were both significantly related to the formation of off-odorants.The major volatile flavor compounds of walnut yogurt included three acids such as caproic acid,three ketones such as acetoin,seven alcohols such as n-hexanol,four aldehydes such as(E)-2-heptenal,butyl butyrate and other compounds.The major volatile compounds with ROAV greater than 1 included(E)-2-heptenal,acetoin,caproic acid,n-hexanol,n-octanol,1-heptanol,benzaldehyde,2-nonanone,2-heptanone,styrene and phenethyl alcohol,and the key flavor compounds were acetoin,caproic acid,(E)-2-heptenal,and n-hexanol.Conclusion:Caproic acid,(E)-2-heptenal,n-hexanol,and benzaldehyde are the major unpleasant odorants of walnut yogurt,and they are mainly formed through lipoxygenase-catalyzed oxidative decomposition of large amounts of linoleic acid and linolenic acid derived from fat hydrolysis during the fermentation process,yielding C_(6)-C_(9) alcohols,aldehydes,and acids.