made a mistake on above & saved it. Tried to reenter using same name and correct a value but it wouldn't take.

Can this be corrected or if not then deleted?

Food > my foods
you should see the edit button on the right so you can make the changes needed (ETA - once you select the relevant food... when you're looking at the list of foods under "my foods" you won't see the edit OR delete button until after you select one of the foods from the list)
IF it's an item you created but kept private (for your own use) you may even see a "delete" button, but if you shared it with the database you can't delete it.