Cleaning food plants: safety and compliance without chemical residues

Summary

This article addresses the crucial issue of cleaning and sanitising in the food industry, a sector regulated by strict hygiene standards such as HACCP. It analyses the criticalities of traditional cleaning methods, which often involve risks of chemical contamination (e.g. caustic soda residues) and biological contamination (e.g. Listeria proliferation due to stagnant water). The article introduces dry ice cryopurification as an alternative and often complementary technological solution, illustrating how it ensures residue-free and water-free cleaning of food systems. The unique benefits of this technology, including the ability to sanitise surfaces, reduce total bacterial load (CBT) and eliminate the rinsing step, are illustrated, with a direct comparison to conventional methods. Finally, practical applications on machinery such as conveyor belts, ovens and packaging lines are described, positioning cryopolishing as the strategic choice for ensuring safety, efficiency and regulatory compliance.

In the food industry, hygiene is the often invisible but crucial link that binds the entire production chain to the safety of the end consumer. It is neither an option nor a negligible detail: it is the foundation on which product quality, brand reputation and compliance with increasingly stringent regulations are built. Every surface, machine and component that comes into contact with food must not only be visibly clean, but also microbiologically safe. The challenge for every company in the industry is therefore to find a method of cleaning food plants that is both effective against the most stubborn dirt, efficient without compromising productivity and, above all, free of collateral risks.

Conventional solutions, based on the use of aggressive chemicals and large quantities of water, while having been the standard for decades, have inherent criticalities that modern technology can and must overcome. DKR cryogenic cleaning emerges as the answer to this need, offering a level of safety, speed and performance unattainable with conventional methods.

Cleanliness requirements in the food industry: the invisible enemy

Working in the food industry means navigating a sea of regulations and protocols, including HACCP (Hazard Analysis and Critical Control Points). This system is not just a manual, but a scientific and systematic approach that requires meticulous analysis of every step in the process to identify, assess and manage potential hazards. When it comes to cleaning, there are two main hazards, both insidious because they are invisible to the naked eye.

• Biological contamination: Organic residues on belts, mixers, hoppers or packaging lines are an invitation to bacteria (such as Listeria, Salmonella, E. coli), yeasts and moulds. The formation of biofilm, a protective matrix created by the microorganisms, makes them even more resistant to traditional sanitisers. The massive use of water in washing, if not followed by perfect and often long drying, can paradoxically aggravate the problem, favouring the proliferation of pathogens such as Listeria monocytogenes, which thrives in damp environments and in the presence of water stagnation.
• Chemical contamination: To combat stubborn dirt, industry makes extensive use of powerful detergents: alkaline such as caustic soda to remove fats and proteins, acid to remove mineral residues and limescale, or chlorine and ammonium quaternary sanitisers. Although effective, these products introduce a new risk. If the rinsing phase is not carried out with meticulous precision, chemical residues may remain on surfaces and migrate into the final product during further processing. This can not only alter the organoleptic properties (taste, smell) of the food, but also represents a serious health hazard for the consumer, especially in the case of allergies or intolerances. It therefore becomes clear that true excellence can only be achieved with residue-free cleaning of food facilities, a method that eliminates the hazard at its root without introducing new ones.

DKR Cryopolysing: the safe choice for Food Safety

Cryogenic cleaning with dry ice is a technology that revolutionises the very concept of industrial cleaning, with sanitising effects. The process uses food grade carbon dioxide (CO2) pellets, the same gas used to carbonate drinks, brought to a solid state (-78.5°C). Thrown onto the surface to be cleaned at high speed by compressed air, they fragilise the contaminants thanks to a triple effect: kinetic impact, thermal shock and sublimation, i.e. the transition from solid to gaseous state. For the food industry, its advantages are unique and decisive:

• Totally dry process, zero water: cryo-cleaning is, by its very nature, an anhydrous process. The CO2 pellets do not dissolve, but sublimate, passing directly from a solid to a gaseous state without leaving any trace of moisture. This advantage is monumental: it eliminates at root the risk of creating an environment favourable to the proliferation of bacteria such as Listeria and prevents the formation of lumps or moulds in machines that process powders such as flour and cocoa.
• Total absence of chemical residues: the cleaning agent is pure carbon dioxide. After it has performed its action, it dissolves in the atmosphere, leaving the surface perfectly clean, dry and free of any chemical agents. This ensures that food plants are cleaned without caustic soda or other aggressive compounds, eliminating the danger of chemical contamination and making any post-wash pH testing unnecessary.
• Intrinsic sanitising action: The thermal shock generated by the impact at -78.5°C not only makes dirt brittle and crumbly, but has a powerful bacteriostatic effect. The drastic and instantaneous drop in temperature reduces the Total Bacteria Charge (CBT) present on surfaces, sanitising the treated area and contributing significantly to maintaining the hygiene standards required by the strictest protocols.

A paradigm shift: operational confrontation

To understand the revolutionary impact of cryo-cleaning, it is useful to compare the workflow of a traditional cleaning operation with that of the DKR method.

Practical applications: versatility in the service of production

The versatility of cryo-cleaning makes it ideal for a wide range of applications. For companies looking for a partner specialising in food plant cleaning in Milan and throughout northern Italy, DKR offers targeted solutions and specialised interventions for

• Conveyor belts and chains (Teflon, steel, plastic): they thoroughly clean links, joints and rollers without having to dismantle them, crushing and removing organic residues, grease and biofilm.
• Baking ovens, tunnels and cooling spirals: effectively remove carbonised residues, fouled oils and greases, even on surfaces that are still hot, drastically reducing cooling times and the risk of fire.
• Packaging machinery, labelling and dosing machines: clean precision mechanisms, sensors, photocells and hot glue nozzles without risk of damage, thanks to a non-abrasive and non-conductive method.
• Silos, hoppers, kneaders and mixers they remove residues of flour, sugar, chocolate and other cooked or sticky ingredients, even in hard-to-reach places, preventing cross-contamination between different batches, especiallyor allergens.

Choose the DKR cryo-cleaning means taking a decisive step towards operational excellence. It is a strategic choice that guarantees maximum food safety, optimises production times and ensures full compliance with the strictest regulations, positioning the company at the forefront of its industry and protecting the most important value: consumer trust.