A Japanese study has shown how easy it is to unintentionally contaminate kitchen utensils with wheat allergens while cleaning.
The study authors used a scrubbing sponge and detergent to clean a bowl coated with 10g of liquid batter, then used the same sponge to wash an unused bowl. Over multiple trials, wheat allergens were found to transfer via the sponge to the unused bowl 80 per cent of the time, even when the sponge was rinsed between uses.
Detailed observation of the residue revealed that proteins including gluten were attached to the cell skeleton, and captured between the skeletons of the sponge, and starch granules were attached to the proteins. Even when the sponge was rinsed, complete removal of wheat allergen was difficult.
These studies indicate that scrubbing sponges for cleaning the residual wheat on cooking utensils should be dedicated exclusively to cooking facilities that prepare allergy-friendly-foods to avoid risk of allergen cross-contact.
The Allergen Bureau has resources that can help food producers prevent accidentally spreading allergens to other parts of the kitchen during cleaning. A cleaning program includes documented and validated cleaning procedures that are designed to remove food allergens and minimise cross contact. Visit our Allergen Risk Review Website to learn more.
Study reference: Hashimoto et al. 2022 Journal of the Food Hygienic Society of Japan. 63(2):70-78. DOI: 10.3358/shokueishi.63.70