Terumot, Chapter Ten, Mishnah Ten
This mishnah deals with vegetables that are pickled together.
1) [Vegetables] pickled together are permitted, except [when pickled] with allium (onions, garlic, leeks).
2) Allim of hullin [pickled] with allium of terumah, or other vegetables of hullin with leeks of terumah are forbidden.
3) But allium of hullin with vegetables of terumah are permitted.
Section one: When vegetables of terumah are pickled together with vegetables of hullin the hullin vegetables do not take on the taste of the terumah vegetables and they remain permitted to non-priests. The exception to this rule is allium vegetables, which includes onions, garlic and leeks. These do impart their taste to other vegetables
Section two: Since terumah onions, garlic or leeks will impart their taste to whatever they are pickled with, the other vegetables must be treated like terumah.
Section three: Garlic, onions and leeks impart their flavor to other vegetables, but they do not take on the flavor of other vegetables. Therefore, if they are hullin and the other vegetables are terumah, they remain hullin.