摘要
产酯酵母是白酒酿造的重要功能微生物,发掘其产香特性并优化产酯条件对白酒酿造技术的提升具有重要意义。以大曲中分离得到的1株异常威客汉姆酵母为出发菌株(命名为Wickerhamomyces anomalus Y-1),对其生长耐受性进行研究,用均匀设计法进行优化试验,结合回归分析考察了培养温度、时间、转速、接种量等因素对其产酯的影响,并采用固相微萃取-气相色谱-质谱联用(SPME-GC-MS)检测风味物质含量。结果表明:该菌株能在pH 3、34℃的环境下生长,且具有一定产酯能力,乙醇体积分数在大于4%时生长开始受到限制,产酯能力也随之下降;在培养温度25.2℃,时间12.2 h,摇床转速180 r/min,接种量9.8%(V/V)的条件下,发酵液中酯类相对含量为680.594μg/L,己酸乙酯相对含量达到380.360μg/L;将SPME-GC-MS测定结果与NIST质谱数据库进行比对,共鉴定出己酸乙酯、辛酸乙酯、β-苯乙醇等40多种对白酒品质有贡献的物质。Wickerhamomyces anomalus Y-1菌株良好的生长耐受性及较强的产酯、产醇能力为下一步应用于浓香型白酒的品质改善奠定了基础。
The main aroma component of Luzhou-flavor liquor is ethyl caproate that has the characteristics of rich aroma, coordinated aroma and so on. However, due to environment, climate, raw materials and other reasons, some Luzhou-flavor liquors have insufficient aroma and poor quality. Some studies have applied ester-producing yeast to the brewing of Luzhou-flavor liquors to improve liquor quality and therefore performed well. Ester-producing yeast is an important functional microorganism in liquor brewing. It is of great significance to explore its aroma characteristics and optimize the ester-producing conditions for the improvement of liquor brewing technology. In this paper, a strain of Wickerhamomyces anomalus Y-1 isolated from Daqu was used as the starting strain. It was found that the yeast could produce ethyl caproate and its growth tolerance was studied. Uniform design method was used to optimize the culture conditions, and SPME-GC-MS was used to detect the content of flavor substances in the fermentation broth. Combined with regression analysis, the effects of culture temperature, time and inoculation amount on the ester production were investigated.The results showed that the strain could grow normally at pH 3 and 34 ℃, and the ability of ester production remained stable. When the ethanol concentration was higher than 4%, the growth of the strain began to be restricted, and the ability of ester production decreased. Under the conditions of cultivation temperature of 25.2 ℃, cultivation time of 12.2 h, rotation speed of 180 r/min and inoculation amount of 9.8%(V/V), the total ester content in the fermentation broth was 680.594 μg/L, and the ethyl caproate content reached 380.360 μg/L. The SPME-GC-MS results were compared with the NIST mass spectrometry database, and a total of 40 substances that contributed to liquor quality were identified, including ethyl caproate, ethyl caprylate, ethyl heptanoate, ethyl valerate, β-phenylethanol, and isoamyl alcohol. It is of great significance for increasing esters and flavoring of Luzhou-flavor liquor. Wickerhamomyces anomalus Y-1 strain showed good growth tolerance and strong ability to produce esters and alcohols. The optimization of culture conditions laid the foundation for the next application in the quality improvement of Luzhou-flavor liquor.
作者
石馨
惠明
田青
黄继红
SHI Xin;HUI Ming;TIAN Qing;HUANG Jihong(College of Biological Engineering,School of Bioengineering,Henan University of Technology,Zhengzhou 450001,Henan)
出处
《河南工业大学学报（自然科学版）》
CAS
北大核心
2022年第1期75-82,共8页
Journal of Henan University of Technology：Natural Science Edition
基金
河南省重大科技专项课题(181100211400-8-2)。
关键词
异常威客汉姆酵母
生长耐受性
均匀设计
主成分分析
己酸乙酯
Wickerhamomyces anomalus
growth tolerance
uniform design
principal component analysis
ethyl caproate
