how long after the use by date is safe to eat mayonnaise?

It depends on the type of mayonnaise and how it is stored. Store-bought mayonnaise that has been unopened and refrigerated lasts up to 2-3 months beyond the "best before" date. Once opened, it typically lasts for 1-2 months in the refrigerator.

Homemade mayonnaise should be consumed within 1-2 weeks for safety reasons, as it is not preserved with the same chemicals as store-bought products. Remember, always check for any signs of spoilage, such as changes in texture, color, or smell, before consuming any mayonnaise past its expiration date.