Any [food] may be used to make an eruv or a shituf, except water and salt. Any [food] may be purchased with tithe funds, except water and salt. One who vowed to abstain from nourishment is permitted water and salt. One may make an eruv for a nazir with wine, or for an Israelite with terumah. Sumchos says: with non-terumah. For a Kohen in a beis-hapras: R’ Yehuda says: Even in a graveyard, because he may go, make a partition, and eat.