Many people are concerned about the food you can’t see – the food left on restaurant tables, school cafeteria tables and in the home kitchen. It’s a valid concern. Some cleaning methods don’t completely remove food allergens. A person with a food allergy may be at risk of having a serious allergic reaction (anaphylaxis) from cross-contact if they eat their food off that surface.

The Food and Drug Administration (FDA) has done a study called “Allergen Removal and Transfer Using Wiping and Cleaning Methods in Retail Food Establishments.” It looks at the best ways to clean to prevent cross-contact from food.

The study focuses on restaurants and retail food vendors. But this study can be helpful for schools too, especially as they look at new ways to manage food allergies due to COVID-19.

The study tested how well different types of cleaning wipes and towels removed allergens from common surfaces used in food service. They put foods with peanut, milk and egg on these surfaces and try different cleaning methods.

They tested these types of surfaces:

• Stainless steel
• Textured plastic
• Maple wood

The study found:

• Scraping food from surfaces before cleaning helped remove food allergens
• Wet wipes/cloths and alcohol/disinfectant (quat) wipes worked better at removing allergens than dry cloths
• If using alcohol/disinfectant wipes, a surface usually needs to be cleaned with more than one wipe
• Wiping for 5 to 10 seconds removed most of the food allergens, except for peanut butter on textured plastic surfaces
• Full cleaning (the wash-rinse-sanitize-air dry method) was good at removing allergens and reducing the transfer of allergens to other surfaces
• Soaking cloths in a sanitizing solution reduced allergen transfer between surfaces
• It was hard to remove food allergens from textured plastic

The study had some limitations, including:

• It did not measure the amount of allergens remaining on the surfaces
• It used single ingredients instead of food mixtures
• The wiping and cleaning was conducted on freshly applied food and the results may have differed if the food had dried on the surfaces

See the full study for more information.