Ozone in Dairy and Cheese Facilities: Mould and Biofilm Control
Introduction
Two threats consistently sit at the top of the quality agenda in dairy and cheese production: unwanted mould growth in ripening and storage areas, and biofilm build-up on pipes, tanks, and gasket surfaces along the processing line. Both directly affect product safety, shelf life, and brand reputation.
This post looks at why mould and biofilm are so persistent in dairy facilities, and how ozone technology addresses both problems with a single system.
Why Is Mould So Common in the Dairy Industry?
Cheese ripening rooms — with high humidity (80-95%), a mild temperature range, and surfaces rich in organic matter — offer a near-ideal environment for mould growth. Species such as Penicillium, Mucor, and Cladosporium readily colonise rinds, shelving, and walls, particularly in hard and semi-hard cheeses.
The issue is not just unwanted mould — some species can produce mycotoxins, creating a direct food safety risk. Uncontrolled mould contamination also drives product returns and batch losses, resulting in significant costs.
Biofilm: An Invisible but Persistent Threat
Biofilm is a protective layer formed when microorganisms attach to a surface within a self-produced polysaccharide matrix. In dairy processing lines, stainless steel pipe joints, gasket gaps, and heat exchanger surfaces are typical high-risk points for biofilm formation.
This matrix provides significant resistance against standard CIP (Clean-in-Place) chemicals — bacteria within biofilm can become 10 to 1000 times more resistant than their free-floating (planktonic) counterparts. Once established, biofilm may not be fully removed even with regular cleaning protocols, turning into a chronic source of contamination.
Limitations of Conventional Methods
Chlorine-based disinfectants and caustic/acid CIP cycles are standard practice in the dairy industry, but chlorine residue can cause unwanted taste and odour issues in products and equipment, and can also form by-products such as trihalomethanes. Fumigation methods, meanwhile, bring operational challenges in ripening rooms in terms of worker safety and required waiting periods.
Furthermore, while chemical disinfectants can affect the outer surface of the biofilm matrix, they generally fail to penetrate deep into the matrix where microorganisms reside.
How Does Ozone Control Mould and Biofilm?
When applied to the air of ripening and storage rooms, ozone gas inactivates airborne mould spores and early surface colonisation through strong oxidation, significantly reducing the mould load in the room when applied continuously or periodically at low concentrations — and remains effective on shelving, wall, and floor surfaces as well.
Ozonated water, when used in CIP lines or surface cleaning, oxidises the polysaccharide structure of the biofilm matrix, weakening it and making it easier to reach the microorganisms inside. This breaks down the biofilm structurally, not just on the surface — an effect chemical disinfectants generally fail to achieve.
Application Points
Typical ozone application points in dairy and cheese facilities include: air disinfection in cheese ripening and storage rooms, ozone injection integrated into CIP water, periodic ozonated water rinsing of tanks and pipelines, and air quality improvement in packaging areas. For each application point, the correct dose, contact time, and equipment material compatibility (stainless steel is ozone-compatible, some elastomers are not) must be assessed individually.
The Advantage of Chemical-Free Processing
Because ozone reverts to oxygen after use, it leaves no chemical residue on the product or equipment. This is a significant advantage both for food safety audits and for dairy and cheese producers targeting a "natural" or "minimally processed" product positioning.
The OCS Ozone Approach
At OCS Ozone, we offer dairy and cheese producers end-to-end ozone solutions, from ripening room air disinfection to CIP line integration. We combine the field experience gained from maintenance-revision projects at facilities such as Sütaş with dose optimisation and equipment compatibility assessment for every new project.
If you would like information about ozone-based solutions for mould or biofilm control at your facility, get in touch.