Abstract: Mixed fermentation of enzyme-producing yeast and Saccharomyces cerevisiae is an effective way to improve the quality and aroma of wine. In this study, yeasts in soil samples from four vineyards in the Changli region were screened and isolated. The diversity of enzyme-producing yeasts in the Changli area were analyzed using lysine medium, WL medium, and screening mediums. The results demonstrated that there were abundant enzyme-producing yeasts in the Changli area. Approximately 50% of the enzyme-producing yeasts produced two or more enzymes simultaneously. The analysis of environmental tolerance to wine brewing showed that three strains (GY1 S.cerevisiae, M9 Torulaspora delbrueckii, and J24 Pichia membranaefaciens) had high sugar tolerance and were suitable for brewing high sugar and low alcohol fruit wines. Strain GY13(Zygosaccharomyces bailii) and strain M9 had high alcohol tolerance, and their activity was high when the alcohol content was 15.000%. Strains J24 and GY1 had high acid tolerance and activity at pH 2.5. Seven strains had high activity at 15 ℃. Comprehensive analysis demonstrated that strain M9 produced β-glucosidase, pectinase and cellulase simultaneously. It had poor acid tolerance but high sugar and alcohol tolerance, as well as low-temperature tolerance. Based on the above results and literature reports, the M9 strain is likely to have a significant application potential for the production of high sugar and low alcohol fruit wines. The above-mentioned enzyme-producing yeasts had different tolerances and may have specific brewing significance for different types of brewing technologies. However, additional brewing studies need to be performed to validate our findings.
 SUN S, GONG H, JIANG X, et al. Selected non-Saccharomyces wine yeasts in controlled multistarter fermentations with Saccharomyces cerevisiae on alcoholic fermentation behaviour and wine aroma of cherry wines[J]. Food Microbiology, 2014(44): 15-23.  LIU PT, LU L, DUAN CQ, et al. The contribution of indigenous non-Saccharomyces wine yeast to improved aromatic quality of Cabernet Sauvignon wines by spontaneous fermentation[J]. LWT-Food Science Technology, 2016, 71(71):356-363.  RENAULT P, COULON J, DE REVEL G, et al. Increase of fruity aroma during mixed T. delbrueckii/S.cerevisiae wine fermentation is linked to specific esters enhancement[J]. International Journal of Food Microbiology, 2015(207): 40-48.  DEBRA R, FLORIAN F B. Exploring the phenotypic space of non-Saccharomyces wine yeast biodiversity[J]. Food Microbiology, 2016(55): 32-46.  GOBBI M, DE VERO L, SOLIERI L, et al. Fermentative aptitude of non-Saccharomyces wine yeast for reduction in the ethanol content in wine[J]. European Food Research and Technology, 2014, 239(1): 41-48.  JOLLY N P, VARELA C, PRETORIUS I S. Not your ordinary yeast: non-Saccharomyces, yeasts in wine production uncovered[J]. FEMS Yeast Research, 2014, 14(2):215-237.  CONTRERAS A, HIDALGO C, HENSCHKE P A, et al. Evaluation of non-Saccharomyces yeasts for the reduction of alcohol content in wine[J]. Applied and Environmental Microbiology, 2014, 80(5): 1 670-1 678.  SOUMYA G, BAHAREH B, HORATIO H M, et al. Assessment of wine microbial diversity using ARISA and cultivation-based methods[J]. Annals of Microbiology,2015, 65(4):1 833-1 840.  ASSIS M O, SANTOS A P C, ROSA C A, et al.Impact of a non-Saccharomyces yeast isolated in the equatorial region in the acceptance of wine aroma[J]. Food and Nutrition Sciences, 2014, 5(9): 759-769.  ESCRIBANO R, GONZÁLEZ-ARENZANA L, GARIJO P, et al. Screening of enzymatic activities within different enological non-Saccharomyces yeasts[J]. Journal of Food Science & Technology, 2017, 54(6): 1 555-1 564.  史学伟, 新疆石河子地区非酿酒酵母菌多样性及其对葡萄酒呈香效应研究[D]. 武汉:华中农业大学, 2015.  FIA G, CANUTI V, ROSI I. Evaluation of potential side activities of commercial enzyme preparations used in winemaking[J]. International Journal of Food Science and Technology, 2014,49(8): 1 902-1 911.  HU Kai, QIN Yi, TAO Yongsheng, et al. Potential of glycosidase from non-Saccharomyces isolates for enhancement of wine aroma[J]. Journal of Food Science, 2016, 81(4): M935-M943.  PALOMO E S, HIDALGO M C, GONZÁLEZ M, et al. Aroma enhancement in wines from different grape varieties using exogenous glycosidases[J].Food Chemistry, 2005, 92(4): 627-635.  杨美景, 河北省昌黎酿酒葡萄产区相关酵母菌分布规律研究[D]. 石家庄: 河北科技大学, 2011.  郝兆, 梁泽鹏, 熊宁,等. 西藏拉鲁湿地土壤酵母菌多样性及产胞外酶活性菌株分布特性研究[J]. 广东农业科学, 2017, 44(4): 99-107.  卢九伟.自选酵母与葡萄酒风味的研究[D]. 石家庄: 河北科技大学硕士学位论文, 2012.  王志恒,冯翠娥,王冲,等. 宁夏玉泉营地区酿酒葡萄酵母菌的分离筛选及分子鉴定[J]. 中国酿造, 2018,37(1):112-115.  李婷,陈景桦,马得草,等. 优选非酿酒酵母与酿酒酵母在模拟葡萄汁发酵中生长动力学及酯酶活性分析[J]. 食品科学, 2017, 38(22): 60-66.  BAFFI M A, TOBAL T, LAGO J H, et al. Wine aroma improvement using a β-lucosidase preparation from Aureobasidium pullulans [J]. Applied Biochemistry & Biotechnology, 2013,69(2): 493-501.  SUN Yue, GUO Jingjing, LIU Fubing, et al. Identification of indigenous yeast flora isolated from the five wine grape varieties harvested in Xiangning, China[J]. Antonie Van Leeuwenhoek, 2014,105(3): 533-540.  MEDINA K, BOIDO E, FARIÜA L,et al. Increase flavour diversity of Chardonnay wines by spontaneous fermentation and co-fermentation with Hanseniaspora vineae[J]. Food Chem, 2013, 141(3): 2 513-2 521.  MATURANO Y P, ASSAF L A, TORO M E, et al. Multi-enzyme production by pure and mixed cultures of Saccharomyces and non-Saccharomyces yeasts during wine fermentation.[J]. International Journal of Food Microbiology, 2012, 155(1): 43-50.  LENCIONI L, TACCARI M, CIANI M, et al. Zygotorulaspora florentina and Starmerella bacillaris in multistarter fermentation with Saccharomyces cerevisiae to reduce volatile acidity of high sugar musts[J]. Australian Journal of Grape and Wine Research, 2018,24(3):368-372.  ASSIS M O,SANTOS A P C,ROSA C A, et al.VImpact of a non-Saccharomyces yeast isolated in the equatorial region in the acceptance of wine aroma[J]. Food and Nutrition Sciences, 2014, 5(9): 759-769.  李爱华, 孙玮璇, 李萍, 等.葡萄汁有孢汉逊酵母β-葡萄糖苷酶的提取与纯化[J].中国食品学报, 2019, 19(6): 150-156.  RANTSIOU K, DOLCI P, GIACOSA S, et al. Candida zemplinina can reduce acetic acid produced by Saccharomyces cerevisiae in sweet wine fermentations[J]. Applied and Environmental Microbiology, 2012, 78(6): 1 987-1 994.  RENAULT P, MIOTSERTIER C, MARULLO P, et al. Genetic characterization and phenotypic variability in Torulaspora delbrueckii species: Potential applications in the wine industry.[J]. International Journal of Food Microbiology, 2009, 134(3): 201-210.  BELY M, STOECKLE P, MASNEUF-POMARÈDE I, et al. Impact of mixed Torulaspora delbrueckii-Saccharomyces cerevisiae culture on high-sugar fermentation[J]. International Journal of Food Microbiology, 2008, 122(3): 312-320.  COMBINA M, ELIA A, MERCADO L, et al. Dynamics of indigenous yeast populations during spontaneous fermentation of wines from Mendoza, Argentina[J]. International Journal of Food Microbiology, 2005, 99(3): 237-243.