本试验以红枣为原料,经提取、过滤和乳酸菌、酵母菌单一及偶联发酵制得相应的红枣发酵样品,对其总糖、总酸、总酚和黄酮含量进行差异分析,采用液相色谱-质谱联用(Liquid chromatograph-mass spectrometer,LC-MS)技术对其游离型酚酸进行差异分析,采用气相色谱-离子迁移谱联用(Gas Chromatography-Ion Migration Spectrum,GC-IMS)技术对其挥发性有机物进行差异分析。结果表明,混菌偶联的发酵方式糖类物质降解效率更高,产酸效率更高,产酚效率更高以及黄酮留存率更高；反式阿魏酸、4-羟基苯甲酸等物质发酵后的样品较发酵前呈上升趋势,反式肉桂酸、香草醛等物质发酵后的样品较发酵前呈下降趋势,没食子酸和原儿茶酸较发酵前样品,在酵母发酵中呈上升趋势,在乳酸发酵和混菌发酵中呈下降趋势；样品气相离子迁移谱分析共鉴别得到挥发性成分53种,主要挥发性成分包括醇类化合物11种,酯类化合物9种,酮类化合物8种,醛类化合物8种,酸类化合物2种,吡嗪吡嗪类化合物2种,未知成分8种；原枣汁中糠醛、3-甲基丁醛等物质的含量较高,乳酸菌发酵样品中2-甲酰基-5-甲基噻吩、2-甲基-1-戊醇等物质的含量较高,酵母菌发酵样品中辛酸乙酯、乙酸乙酯等物质的含量较高,混合发酵样品中甲醇等物质的含量较高；样本间差异明显,其中乳酸菌发酵样品与混菌发酵样品的风味较为相似,原枣汁、酵母菌发酵样品与其他样品间差异较大。本试验有助于推动混菌发酵在红枣酵素发酵生产行业的应用,并提供相应的理论基础和科学实践依据。

This test takes jujube as raw material, the corresponding jujube fermentation sample is made by extraction, filtration and single and coupled fermentation of lactic acid bacteria and yeast, the difference analysis is made on the contents of total sugar, total acid, total phenol and flavone, Liquid chromatograph-mass spectrometer, LC-MS technology was used to analyze the difference of free phenolic acids, and Gas Chromatography-Ion Migration Spectrum (GC-IMS) technology was used to analyze the difference of volatile organic compounds. The results showed that the hybrid fermentation method had higher degradation efficiency of carbohydrates, higher acid production efficiency, higher phenol production efficiency and higher retention rate of flavonoids. Compared with the samples before fermentation, the samples after fermentation of trans ferulic acid and 4-hydroxybenzoic acid showed an increasing trend, the samples after fermentation of trans cinnamic acid and vanillin showed a decreasing trend, the samples after fermentation of gallic acid and protocatechuic acid showed an increasing trend in yeast fermentation, but showed a decreasing trend in lactic acid fermentation and mixed bacteria fermentation. A total of 53 volatile components were identified by gas phase ion migration spectrometry. The main volatile components included 11 alcohols, 9 esters, 8 ketones, 8 aldehydes, 2 acids, 2 pyrazines, and 8 unknown components. The contents of furfural and 3-methylbutyral in jujube juice were higher, the contents of 2-formyl-5-methylthiophene and 2-methyl-1-amyl alcohol in lactic acid bacteria fermentation samples were higher, the contents of ethyl octanoate and ethyl acetate in yeast fermentation samples were higher, and the contents of methanol in mixed fermentation samples were higher. There were obvious differences among the samples, among which the flavor of the lactic acid bacteria fermented sample and the mixed bacteria fermented sample was similar, while the original jujube juice, yeast fermented sample and other samples were significantly different. This experiment is helpful to promote the application of mixed fermentation in jujube fermentation production industry, and provides the corresponding theoretical basis and scientific practice basis.

山西省科技成果转化引导专项(202104021301051)