Soundness of mind

Does mayonnaise need to be refrigerated?

Yes, mayonnaise should be kept in the refrigerator at all times. Refrigeration will help prevent spoilage and ensure the mayonnaise stays fresh and safe to eat. It should be stored in an airtight container and used within a few weeks of opening.

How long can you leave mayonnaise out unrefrigerated?

According to the U.S. Department of Agriculture, mayonnaise should not be left out of the refrigerator for more than two hours. After this time, bacteria can start to grow on the mayonnaise, making it unsafe to eat. If the temperature is above 90°F, the mayonnaise should not be left out for more than one hour. It is recommended that mayonnaise be refrigerated at 40°F or lower.

Why does unopened mayo not need to be refrigerated?

Unopened mayonnaise does not need to be refrigerated because the vinegar and lemon juice used as preservatives inhibit the growth of bacteria and other microorganisms that require warm temperatures to survive. Additionally, the high fat content of mayonnaise blocks the growth of bacteria and other microorganisms, allowing it to stay safe at room temperature. For best results, store unopened mayonnaise in a cool, dry place and be sure to refrigerate it once it is opened.