Musannaf Ibn Abi Shayba 16:205

Abu Bakr narrated to us, he said: Abd al-Rahim ibn Sulayman narrated to us, from Yazid ibn Abi Ziyad, who said: We entered upon a shepherd who invited us to food, and he brought us nabidh (a drink), so I disliked it. Then Ali—Abu Bakr said: It ought to be Ali ibn al-Husayn ibn Ali—took it and drank it. He said: If you enter upon your Muslim brother, then eat from his food and drink from his drink.