Beets are another vegetable that should not be reheated. Like spinach and celery, They may be large in nitrates, which convert into unsafe nitrites when reheated. Reheating leftover cooked beets could certainly be a risky endeavor that you might want to skip. Leftover Gravy and Pan Drippings (picture credits: flickr) https://nikosd962jkm1.wikiconverse.com/user