The Cheese Production Facility Microbiome Exhibits Temporal and Spatial Variability.

Area of Science:

• Food Microbiology
• Environmental Microbiology
• Industrial Microbiology

Background:

• Product quality in cheese manufacturing is paramount, yet microbial variability in production environments remains poorly understood.
• Temporal and facility-specific changes can significantly alter microbial subpopulations, potentially affecting final cheese characteristics.

Purpose of the Study:

• To quantify day-to-day and facility-to-facility variations in the cheese production microbiome.
• To identify key microbial groups and environmental factors contributing to these variations.
• To assess the impact of these variations on cheese quality.

Main Methods:

• Sampling of in-process milk, cheese, and food-contact surfaces across three facilities over three production days.
• Microbial community characterization using 16S rRNA metabarcoding and selective plating.
• Analysis of microbial diversity and variance attributed to facility and daily changes.

Main Results:

• Significant facility-facility and day-to-day microbial differences were observed across all sample types.
• Food contact surfaces showed the greatest facility-driven variance (25-41%), while milk and cheese exhibited greater day-to-day variance (20% and 29%, respectively).
• Lactococcus starter culture rotation was a primary driver of facility differences in cheese, while Streptococcus and Acinetobacter were notable in milk and on surfaces.

Conclusions:

• The cheese facility microbiome is complex, exhibiting substantial daily and facility-specific microbial variations.
• These variations, influenced by starter cultures and environmental surfaces, can impact cheese quality and necessitate repeated sampling for accurate assessment.
• Understanding these dynamics is crucial for ensuring consistent product quality in cheese manufacturing.