Characterization of Indigenous Lactic Acid Bacteria in Cow Milk of the Maltese Islands: A Geographical and Seasonal Assessment

• Main Authors: Elisa Garroni, Agapi I. Doulgeraki, Foteini Pavli, David Spiteri, Vasilis P. Valdramidis
• Format: Article
• Language: English
• Published: MDPI AG 2020-05-01
• Series: Microorganisms
• Subjects: milk; lactic acid bacteria; microbial diversity; geographical distribution; seasonality
• Online Access: https://www.mdpi.com/2076-2607/8/6/812

A geographical and seasonal assessment of indigenous lactic acid bacteria (LAB) in Maltese cow milk was conducted in this study. To investigate this, milk was collected from different regions of Malta during winter and summer seasons. Total viable counts (TVC) and LAB population were enumerated. Afterwards, LAB were isolated and identified by molecular methods. According to the results, similar TVC were enumerated on winter and summer samples, while highest LAB population was detected on summer samples. LAB isolates were grouped in seven different clusters which were assigned to <i>Lactobacillus casei</i>, <i>Pediococcus</i> <i>pentosaceus</i>, <i>Lactobacillus</i> <i>plantarum</i>, <i>Weissella</i> <i>paramesenteroides</i>, <i>Lactobacillus</i> <i>rhamnosus</i>, <i>Lactococcus</i> <i>lactis</i><i>,</i> and <i>Lactococcus</i> <i>garvieae</i>. In addition, <i>Enterococcus</i> and <i>Streptococcus</i> species were also isolated. Season seemed to affect the genus / species of LAB since <i>Lactobacill</i><i>us</i> were mainly isolated from winter samples, while <i>Lactococcus</i> and <i>Enterococcus</i> species were the main genera identified in summer samples. Regarding the geographical distribution, the majority of the <i>Lactobacillus</i> spp. were isolated from the South-eastern region in both seasons. In conclusion, through this study the diversity of indigenous LAB in the Maltese cow milk was monitored for the first time and highlighted that the microbial communities are affected by seasonality and geographical distribution of the farms.