Fish cooked in Vinegar. Many have the custom not to use vinegar in any of the cooking. And some have the custom not to use lemon juice at all and use orange juice instead.
Nuts cause it causes phlegm and gematria chait
According to Mishnah Berurah the Vilna Gaon said not to eat Grapes.
Many Ashkanazi have the custom to not eat anything savory, sour, or spicy and only eat sweet foods.
