Biofilm

Biofilm is a community of microorganisms attached to a surface and embedded in a self-produced protective matrix. In food premises, biofilms can develop on equipment, drains, pipes, ice machines, beverage nozzles, gaskets and other damp or difficult-to-clean areas. They can make microorganisms harder to remove and increase the risk of persistent contamination.

How biofilms form

Microorganisms attach to a surface, multiply and produce a matrix made from substances such as polysaccharides, proteins and extracellular DNA. The matrix helps the community adhere to the surface and can reduce the effectiveness of routine cleaning if it is allowed to build up.

Where kitchens may find biofilms

• Drains and floor channels with persistent moisture and food residue.
• Ice machines, beverage dispensers and soda gun nozzles.
• Gaskets, seals, joints and internal surfaces of food-processing equipment.
• Hard-to-reach areas of slicers, mixers and other equipment that are not fully disassembled for cleaning.

How to control biofilms

Follow a documented cleaning and sanitation procedure that removes food soil and biofilm material using the correct detergent, mechanical action, disassembly and contact time. Rinse where required, then apply an approved sanitizer at the specified concentration and contact time. Inspect equipment and verify cleaning effectiveness using the methods in the food-safety plan. Sanitizer alone may not penetrate or remove an established biofilm.

Chef’s tip: Pay particular attention to drains, seals, gaskets and equipment that stay wet. A surface that looks clean may still require disassembly and inspection under the operation’s sanitation procedure.

Key distinction: Biofilm is an attached microbial community protected by a matrix; it is not simply a visible layer of slime or ordinary food residue.