基于生物脱腥的扇贝挥发性风味成分解析

Analysis of Volatile Flavor Components in Scallop Based on Biological Deodorization

目的:解析扇贝微生物发酵对其主要挥发性风味成分的影响,阐明生物脱腥作用机制。方法:结合臭氧减菌预处理,分别采用单菌(乳杆菌RP38)和混菌(乳杆菌RP38+酿酒酵母JJ4)对扇贝进行生物脱腥,顶空固相微萃取与气-质谱联用(HS-SPME-GC-MS)法解析挥发性风味成分,通过多元统计学方法及相对气味活度值(ROAV)法明确生物脱腥扇贝的主体风味活性成分。结果:臭氧处理使菌落总数降低约1个数量级,减少48.4%的挥发性盐基氮(TVB-N),对风味影响不大。扇贝生物脱腥前、后的差异风味由醛类和醇类物质构建,生物发酵主要降解低级饱和醛类和烯炔类,增加不饱和脂肪醛、醇类和酮类物质。主成分分析显示:单菌发酵特征产物为正庚醇、红没药醇和(2E)-2-壬醛等,混菌发酵特征产物为1-戊醇、苯甲醛、反-2-辛烯醛和新铃兰醛等,混菌发酵带来更丰富多样的挥发性风味成分。ROAV分析表明:扇贝主体挥发性风味活性成分是正辛醛、(2E)-2-壬醛、壬醛、1-壬醇、庚醛和癸醛,正庚醇、2-壬酮、(2Z)-2-庚烯醛和反-2-辛烯醛是生物脱腥后风味的重要修饰成分。结论:臭氧处理能较好地保持扇贝鲜度;生物脱腥主要通过降解腥味特征的低级醛类物质,生成清新特征的不饱和醛类和醇类成分;混菌发酵可实现脱腥增效。

Objective:To analyze the effects of biological deodorization by microbial fermentation of scallop on the main volatile flavor components of scallop,and to clarify the mechanism of biological deodorization.Method:Combined with ozone pretreatment,respectively adopt single bacteria(Lactobacillus RP38)and mixed bacteria(Lactobacillus RP38+Saccharomyces cerevisiae JJ4)to biological trends of scallops.The volatile flavor components were analyzed by headspace solid phase microextraction coupled with gas chromatography-mass spectrometry(HS-SPME-GC-MS),and identified by multivariate statistical methods and ROAV(relative odor activity value).Results:Ozone treatment could reduce the total number of bacterial colonies by about 1 order of magnitude and 48.4% TVB-N,which had little effect on flavor.The different flavor of scallop before and after biological deodorization was constructed by aldehydes and alcohols.The low saturated aldehydes and alkynes were mainly degraded by biological fermentation,and unsaturated fatty aldehydes,alcohols and ketones were increased.Principal component analysis showed that the characteristic products of single fermentation were 1-heptanol,α-bisabolol,(2E)-2-nonenal,etc.,while the characteristic products of mixed fermentation were 1-pentanol,benzaldehyde,(2E)-2-octenal and lyral,etc.The mixed fermentation could produce more abundant and diverse volatile flavor components.ROAV analysis showed that the active components of volatile flavor of scallop were octanal,(2E)-2-nonanal,nonanal,1-nonanol,heptanal and capraldehyde.1-Heptanol,2-nonanone,(2Z)-2-heptenal and(2E)-2-octenal were the important flavor modifying components after biological deodorization.Conclusion:The ozone treatment could maintain the freshness of scallop.Ozone treatment could keep scallop fresh.Biological deodorization mainly through degradation of low-grade aldehydes with odor characteristics,and the fresh unsaturated aldehydes and alcohols were produced.The mixed fermentation could achieve the synergistic deodorization effect.