How microwave technology is perceived? A food safety cross-cultural study between Brazil and Portugal

This study aimed to verify the knowledge related to domestic microwave ovens by Brazilians (n = 494) and Portuguese (n = 460). A questionnaire with 24 questions about use, knowledge, safety practices, and attitudes considering microwave ovens and microwave-treated foods was used. Brazilian and Portuguese use microwave ovens mainly for reheating, defrosting, cooking, and using utensils labeled safe for microwaves. Furthermore, the migration of compounds from the container to the food and textural changes were the main concerns reported. Brazilians use more microwave ovens to reheat and cook frozen commercial foods. However, 3.6% of Brazilians still use metal containers, 19.7% do not read the instructions for reheating, and 12.2% do not read the cooking instructions. Portuguese consumers had a higher understanding of the potency applied in the microwave oven, a parameter closely linked to heating uniformity and the formation of cold spots, which can pose microbiological risks. Furthermore, they allow food to stand still before consuming it, promoting a more uniform heat distribution, and minimizing the formation of cold spots. Perceived safety indices when consuming microwave-treated foods were calculated at 5.7 for Brazilians and 6.4 for Portuguese on a 9-point scale, demonstrating that they were indifferent or considered microwaved-treated products as slightly safe, respectively. People with different levels of education showed different knowledge about the technology, indicating the greater need for information dissemination to reach the population with the lowest level of education.