Verification of the safety of pack-cooking methods for managing food allergies during disasters

• For pack-cooking, the stew being cooked can be a heat source. • Heat-resistant, food-grade high-density polyethylene bags are used for pack-cooking. • No substances from the polyethylene bag leach out during pack-cooking. • No allergen contamination occurred inside the polyethylene bag. • Pack-cooking is a promising method for people with allergies during disasters. Disaster evacuee s with food allergies are at high risk of nutritional deficiencies and allergic reactions, making survival difficult. This study aimed to investigate chemical and allergen contamination when allergen-free foods were cooked in transparent polyethylene bags (pack-cooking) in boiled food (for distribution) to provide individualized disaster food support for food allergy sufferers, assuming limited heat sources and drinking water. Residual evaporation migrating from various polyethylene bags was measured through elution tests using food -simulating solvents , following the Japan Positive List (PL) System guidelines. For evacuees with allergies, samples of pack-cooked rice and allergen-free stew wrapped in two layers of polyethylene bags were cooked with a white stew containing allergenic ingredients (wheat, milk, and eggs). Allergenicity was assessed using commercially available enzyme-linked immunosorbent assay (ELISA), western blotting kits, and polymerase chain reaction (PCR) method. Residual evaporation from all six types of polyethylene bags was below the standard values set by the Japan PL. The protein content derived raw material, measured per gram of sampled weight was significantly lower (p ≤ 0.001) in the pack-cooked meal than in the white stew, with a maximum detected level of 2.5 µg/g for wheat protein in the pack-cooked stew. Thus, the protein content of all pack-cook ed meals was below Japan's labeling threshold (10 μg protein per gram of food). A small amount of wheat-, egg- and milk-derived protein was detected in the ELISA test, but no allergens were identified in the western blotting and PCR. These results suggest that allergen-free meals can be safely prepared using polyethylene bags that can be heated in hot water, even in dishes containing allergens. Pack-cooking may serve as a practical method to support the mental and physical well-being of individuals with food allerg ies sufferers during disasters, when conventional meal preparation is often difficult .