Department of Food Engineering, Faculty of Engineering, Hitit University, Corum, Turkey.
Department of Food Engineering, Faculty of Engineering, Hacettepe University, Beytepe, Ankara, Turkey.
J Appl Microbiol. 2021 Aug;131(2):801-818. doi: 10.1111/jam.14979. Epub 2021 Jan 8.
To determine the technological and enzymatic characteristics of 54 yeast strains belonging to 16 species previously isolated from natural fermentation media of Gemlik olives. The distinguishing feature of these strains, according to their selective technological and enzymatic properties using principal component analysis (PCA), was also intended.
The technological properties of yeast strains, growth characteristics at different temperatures, pH and salt concentrations were examined. Besides, yeast strains' abilities to use oleuropein as a sole carbon source, to assimilate citric acid and to produce H S were examined and their catalase, pectolytic, proteolytic and killer activities were also tested. All strains could grow between 15 and 28°C which are favourable temperatures for natural olive fermentation and they were able to tolerate high salt concentration and low pH in the brine of natural fermentation media. As a result of enzymatic characterization with API-ZYM test system, all strains have esterase activity, which is an important feature for developing table olive aroma. In this research, β-glucosidase activity, which contributes to removing bitterness out of olives, was one of the main distinguishing features of yeast strains. Several strains of Candida hellenica, Pichia anomala and Candida pelliculosa species had β-glucosidase activity. PCA tested yeasts and several strains belonging to C. hellenica (AF84-1), P. anomala (BF1-1, BF46-2) and C. pelliculosa (BF46-3, BF143-2) species have promising technological and enzymatic properties for natural table olive production.
Five promising strains belonging to C. hellenica, P. anomala and C. pelliculosa species may be suitable adjunct starter cultures with lactic acid bacteria in natural fermentation media of table olive.
This study has been the first contribution to the enzymatic and technological characterization of yeasts isolated from Gemlik olives in Turkey. Some strains could be proposed as a promising adjunct culture in the production of table olives.
确定从盖姆利克橄榄天然发酵介质中分离出的 16 个种的 54 株酵母菌株的技术和酶学特性。根据主成分分析（PCA）的选择性技术和酶学特性，也确定了这些菌株的区别特征。
研究了酵母菌株的技术特性、不同温度、pH 值和盐浓度下的生长特性。此外，还检查了酵母菌株利用橄榄苦苷作为唯一碳源、同化柠檬酸和产生 H 2 S 的能力，并测试了它们的过氧化氢酶、果胶酶、蛋白酶和杀真菌活性。所有菌株都可以在 15 到 28°C 之间生长，这是橄榄天然发酵的适宜温度，并且能够耐受天然发酵介质盐水的高盐浓度和低 pH 值。通过 API-ZYM 测试系统进行的酶特性分析表明，所有菌株都具有酯酶活性，这是开发橄榄香气的重要特征。在本研究中，β-葡萄糖苷酶活性是酵母菌株的主要区别特征之一，有助于去除橄榄的苦味。几种希氏酵母、异常毕赤酵母和皱褶假丝酵母的菌株具有β-葡萄糖苷酶活性。PCA 测试的酵母和几种属于希氏酵母（AF84-1）、异常毕赤酵母（BF1-1、BF46-2）和皱褶假丝酵母（BF46-3、BF143-2）的菌株具有适合在橄榄天然发酵介质中生产天然橄榄的有前途的技术和酶学特性。
属于希氏酵母、异常毕赤酵母和皱褶假丝酵母的 5 株有前途的菌株可能适合与乳酸菌一起作为天然橄榄发酵中的辅助起始培养物。
本研究首次对从土耳其盖姆利克橄榄中分离的酵母进行了酶学和技术特性分析。一些菌株可以作为生产橄榄的有前途的辅助培养物。
