Genomic diversity and thermal niches of Aspergillus molds disrupting rind formation of surface-ripened cheeses.

Aspergillus westerdijkiae contaminates artisan cheeses across multiple facilities and exhibits diverse genomic types with variable ochratoxin A production.

• Why it matters: Understanding the natural history and environmental constraints of cheese spoilage molds like Aspergillus is crucial for managing contamination and ensuring food safety.
• What they did: The study used comparative genomics, RNA-sequencing, and temperature-growth experiments on isolates from cheese facilities to analyze diversity, gene expression, and growth preferences of Aspergillus species.
• The result: Spoilage Aspergillus species have higher optimal growth temperatures than desirable cheese fungi and are outcompeted at temperatures below 15°C, suggesting temperature control may help limit contamination.