Department of Food Engineering, Faculty of Engineering, Van Yuzuncu Yil University, 65080, Van, Turkey.
Antonie Van Leeuwenhoek. 2024 May 30;117(1):85. doi: 10.1007/s10482-024-01982-w.
Kars Kashar cheese is an artisanal pasta-filata type cheese and geographically marked in Eastern Anatolia of Turkey. The aims of this research were to determine for the first time thermophilic lactic acid bacteria (LAB) of Kars Kashar cheese and characterize the technological properties of obtained isolates. In our research, a number of 15 samples of whey were collected from the different villages in Kars. These samples were incubated at 45 °C and used as the source material for isolating thermophilic LAB. A total of 250 colonies were isolated from thermophilic whey, and 217 of them were determined to be presumptive LAB based on their Gram staining and catalase test. A total of 170 isolates were characterized by their phenotypic properties and identified using the MALDI-TOF mass spectrometry method. Phenotypic identification of isolates displayed that Enterococcus and Lactobacillus were the predominant microbiota. According to MALDI-TOF MS identification, 89 isolates were identified as Enterococcus (52.35%), 57 isolates as Lactobacillus (33.53%), 23 isolates as Streptococcus (13.53%), and one isolate as Lactococcus (0.59%). All thermophilic LAB isolates were successfully identified to the species level and it has been observed that MALDI-TOF MS can be successfully used for the identification of selected LAB. The acidification and proteolytic activities of the isolated thermophilic LAB were examined, and the isolates designated for use as starter cultures were also genotypically defined.
卡尔斯卡沙尔干酪是一种采用意大利乳清干酪工艺制作的、具有地域标志的奶酪,产于土耳其东安纳托利亚地区。本研究的目的是首次对卡尔斯卡沙尔干酪中的嗜热乳酸菌(LAB)进行鉴定,并对获得的分离株的技术特性进行分析。在研究中,从卡尔斯的不同村庄收集了 15 份乳清样本。这些样本在 45°C 下孵育,作为分离嗜热 LAB 的原始材料。从嗜热乳清中总共分离出 250 个菌落,其中 217 个根据革兰氏染色和过氧化氢酶试验被确定为疑似 LAB。总共对 170 个分离株进行了表型特性的鉴定,并通过 MALDI-TOF 质谱法进行了鉴定。分离株的表型鉴定显示,肠球菌和乳杆菌是主要的微生物群。根据 MALDI-TOF MS 鉴定,89 个分离株被鉴定为肠球菌(52.35%),57 个分离株被鉴定为乳杆菌(33.53%),23 个分离株被鉴定为链球菌(13.53%),1 个分离株被鉴定为乳球菌(0.59%)。所有嗜热 LAB 分离株都成功地鉴定到种水平,并且已经观察到 MALDI-TOF MS 可以成功地用于所选 LAB 的鉴定。还对分离出的嗜热 LAB 的酸化和蛋白水解活性进行了检测,并对用于发酵剂培养的分离株进行了基因型定义。