柑橘果皮中生香酵母的筛选及挥发性香气 成分分析

目的 从微生物众多的柑橘中筛选得到生香酵母。方法 从四川地区的柑橘果皮中筛选出4株产生浓郁香味的生香酵母, 通过形态学、生理生化特征和ITS序列特征进行分析鉴定, 并利用顶空固相微萃取-气质联用技术检测其发酵产生的挥发性香气, 依据风味贡献理论比较不同菌株发酵的主体香气成分。结果 4株菌株(Y3、Y7、Y11、Y13)分别鉴定为桔假丝酵母(Candida quercitrusa)、蜜二糖假丝酵母(Candida melibiosica)、毕赤酵母(Pichia sp.1 TMS-2011)、异常威克汉姆酵母(Wickerhamomyces anomalus), Y3的主体香味成分为2-壬醇、苯乙醇, Y7、Y11、Y13最主要的香气成分均为苯乙醇, 且苯乙醇相对含量均在30%以上。结论 分离得到的生香酵母具有发酵增香功能, 在柑橘果醋工业化生产中潜力巨大。

Screening of yeast in citrus peels and their volatile aromatic components analysis

Objective To screen an aroma-producing yeast in many microorganisms in citrus. Methods Four strains of aroma-producing yeasts were selected from the citrus peels produced in Sichuan province, the strains were identified based on morphological, physiological, biochemical characteristics and ITS sequence analysis.The types and content of volatile aromatic components were analyzed by SPME-GC-MS(Headspace solid phase microextraction combined with Gas chromatography-Mass spectrometry). The aroma values were calculated according to aroma contribution theory. Results The strains(Y3, Y7, Y11 and Y13) were identified as Candida quercitrusa, Candida melibiosica, Pichia sp. 1 TMS-2011 and Wicker hamomyces anomalus. The results indicated that the main components of Y3 were 2-nonyl alcohol and benzene ethanol and the main components of Y7, Y11, and Y13 were benzene ethanol. Conclusion Aroma-producing yeast isolated with fermentation fragrance has great potential to produce citrus vinegar in industrial production.