[关键词]
[摘要]
猕猴桃果酒香气与发酵用酵母菌株关系十分密切,本研究从猕猴桃果实的果皮上分离酵母菌株,经过纯化、筛选、鉴定得到适于猕猴桃果酒酿制的酵母菌株,并采用GC-MS分析其对猕猴桃果酒香气组成和含量的影响。结果表明:筛选得到的2株酵母菌1-21和1-31经26SrDNA鉴定分别为酿酒酵母和东方伊萨酵母,与商业酿酒酵母相比,1-21具有发酵力强、耐酸性强和果酒中抗坏血酸含量高等特性,1-31具有耐高浓度SO2特性和果酒香气独特的特性。通过比较,不同酵母菌株所酿制猕猴桃果酒的香气成分在组成和含量上存在特异性差异,49种检出组份中有13种是相同的香气成分,8种为1-21菌株所酿猕猴桃果酒所独有,7种为1-31菌株所酿猕猴桃果酒所独有。此外,筛选菌株酿制的猕猴桃果酒香气组份含量明显高于商业菌株,因此认为筛选菌株能更好的表达猕猴桃果酒的特征香气。
[Key word]
[Abstract]
The aroma of kiwifruit wine is closely dependent on the yeast strains used for fermentation. In this study, yeast strains were isolated from kiwifruit peel, and strains suitable for kiwifruit wine fermentation were obtained after purification, screening, and identification. The effects of the screened strains on the aromatic composition and content of kiwifruit wines were determined by gas chromatography coupled with mass spectrometry (GC-MS). The results showed that two screened yeast strains (1-21 and 1-31) were identified as Saccharomyces cerevisiae (baker’s yeast) and Issatchenkia orientalis, respectively, by using 26S rDNA sequencing. Compared with the commercially available yeast strain, the screened yeast strain 1-21 showed a stronger fermentation capacity, stronger acid resistance, and produced higher ascorbic acid content in wine. In contrast, strain 1-31 was more resistant to high sulfur dioxide concentration and produced a unique aroma in wine. By comparison, characteristic differences in the aromatic composition and content were found in the kiwifruit wines fermented using different yeast strains. Among the 49 identified aromatic compounds, 13 were common aromatic components, eight were only found in the kiwifruit wine fermented using strain 1-21, and seven were only found in the kiwifruit wine fermented using strain 1-31. In addition, the aromatic compound content in kiwifruit wines fermented using the screened strains was significantly higher than that in kiwifruit wine fermented using a commercially available yeast strain. Therefore, the screened yeast strains 1-21 and 1-31 were considered more suitable for producing the characteristic aroma of kiwifruit wine.
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[基金项目]
陕西省科学技术研究发展计划项目(2012k01-26);西北农林科技大学博士科研启动基金(2010BSJJ052)