Producing high-quality cheese requires skill and tradition - it demands strict control of microbial activity throughout the entire process. From the farm to the cheese plant, unwanted bacteria can lead to off flavours, cracks, gas formation, and other costly defects.
Managing Risk on the Farm
The farm environment is full of microorganisms - some beneficial, others harmful. Contaminants can come from soil, water, feed, bedding, or equipment. Animal manure can also carry pathogens like E.coli, Listeria, and Salmonella. To minimise risk, farmers must ensure that udders are cleaned and sanitised properly before milking, and that milking systems are maintained and washed under the right conditions.
If cleaning temperatures, times, or chemical concentrations fall short, biofilms can form on equipment. These thin layers of bacteria and milk residues are difficult to remove and can continuously contaminate fresh milk. Proper sanitation and rapid cooling of milk immediately after collection are key to maintaining low bacterial counts and ensuring product safety.
Contamination Control in the Plant
Within the cheese plant, pasteurisation is a critical step for ensuring safety. If pasteurisers are not properly cleaned or are operated for long periods without washing, biofilms can develop and harbour heat-tolerant bacteria. These bacteria can survive processing and cause gas production, slits, or cracks in cheese.
Storage and ripening conditions also play a major role in final product quality. While raising ripening temperatures may speed up the aging process, it often results in unbalanced flavours and structural defects. Controlled, consistent conditions are essential for uniform texture and flavour development.
Modern Tools and Research
Emerging research shows that certain non-starter bacteria can produce gases and biogenic amines - compounds that not only cause physical defects but also unpleasant odours and tastes. Advanced genomic tools are now helping cheesemakers identify and trace microbial sources more precisely, enabling faster corrective action.
Building a Culture of Prevention
A proactive approach that combines sanitation, equipment maintenance, and scientific monitoring helps cheesemakers prevent defects before they occur. Continuous training, process audits, and new diagnostic technologies all play a role in strengthening quality control.
By understanding and managing the microbiology behind cheese production, processors can protect product integrity, reduce waste, and delivery the safe, flavourful cheeses consumers expect.