How long will unopened mayonnaise keep unrefrigerated?

Mayonnaise is an oil-in-water emulsion, meaning it is made up of oil droplets dispersed in water. The oil in mayonnaise can go rancid over time, especially if it is exposed to heat or light. For this reason, mayonnaise should be refrigerated after opening to prevent it from spoiling.

Unopened mayonnaise will typically last for about 3 months at room temperature. However, it is best to store unopened mayonnaise in the refrigerator to extend its shelf life. Mayonnaise that has been stored in the refrigerator can typically last for up to 6 months.

If you are not sure whether or not mayonnaise is still good, it is best to err on the side of caution and throw it out. Spoiled mayonnaise can cause food poisoning, which can lead to vomiting, diarrhea, and abdominal cramps.