According to the United States Department of Agriculture (USDA), mayonnaise should be refrigerated after opening to maintain its safety and quality. The USDA recommends that perishable foods, including mayonnaise, should not be left out at room temperature for more than two hours. This guideline helps prevent the growth of harmful bacteria that can cause foodborne illnesses.
The Role of Temperature in Mayonnaise Preservation
Temperature plays a critical role in the preservation of mayonnaise. At room temperature, bacteria can multiply rapidly, increasing the risk of spoilage and foodborne illness. Refrigeration slows down bacterial growth, thereby extending the shelf life of mayonnaise. Ideally, mayonnaise should be stored at temperatures below 40°F (4°C) to ensure its safety.