Certain cleaning strategies, validation prevent allergen cross-contamination during processing.

Consumers with food allergies rely on product labels to disclose the presence of allergenic ingredients in products. However, undeclared allergens can be inadvertently introduced into a product by cross-contact during its manufacture.

Shared processing equipment that is poorly cleaned may be a cause of such cross-contact and contamination. A project at the National Center for Food Safety and Technology has examined cleaning protocols for removing allergenic foods from food-contact surfaces, as well as techniques for validating the efficacy of cleaning. Investigators indicate that processors should evaluate the efficacy of cleaning protocols for each type of food soil, food-contact surface, piece of equipment and processing line.

The main objective of researchers was to measure the efficacy of different cleaning protocols for removing hot milk, cold milk and peanut butter soils from plates made of different food-contact materials. Plates were contaminated with a known amount of either peanut butter or milk, and then were washed with various types of cleaning agents or solutions--water, chlorinated alkali cleaner (CAD) and acid detergent (AD)--at different temperatures for 30 minutes.

After the plates were cleaned, investigators examined them for the presence of milk or peanut residues. The plates were swabbed to measure milk and peanut residue levels using ELISA kits. Visual inspection of the plates was an effective way to detect the presence of milk and peanut residues after all washing procedures were completed.

The efficacy of the cleaning protocols differed depending on the type of soil, the food-contact surface and the concentration of the detergent in the cleaning solution. Cleaning the plates with room temperature water allowed detectable residues of milk or peanut to remain. Hot water was able to remove cold milk soils, but not hot milk or peanut butter soils on some types of surfaces. Hot CAD and AD solutions prepared using the manufacturers' suggested concentrations were successful at removing the food soils from all the materials studied.

Further information. Lauren Jackson, National Center for Food Safety and Technology, FDA, 6502 S. Archer Rd, Summit-Argo, IL 60501; phone: [phone]; email: [e-mail].