Microbial dynamics in Vorarlberger Alpk?se

Vorarlberger Alpk?se (VA) is a Protected Designation of Origin (PDO) Austrian heritage cheese produced from raw milk during the summer grazing period in the Alps. This study investigates raw milk and cheese microbiota from two alpine farms. Raw milk, curd, and cheese samples were collected and analysed using 16S rRNA gene amplicon sequencing to determine the microbial community composition. The microbial community in raw milk showed significant variation during the alpine sojourn, with psychrotrophic microorganisms predominating due to continuous cooling, while Lactobacillus levels decreased over time. The cheese microbiota was initially diverse, with Pseudomonas, Acinetobacter, Escherichia-Shigella, Hafnia-Obesumbacterium and Lactobacillus being the most abundant genera in the curd. During ripening, Lactobacillus became the predominant genus, while the overall diversity decreased. Differences in microbial communities were observed between the two farms, likely due to variations in production conditions and domestic flora. These findings highlight the impact of alpine farming practices on the raw milk and cheese microbiota, influencing the unique characteristics of VA