Musannaf Ibn Abi Shaybah 25438 — The permission for nabidh, and those

It is narrated from Hammam, who said: Raisin nabidh of Ta'if was brought to Sayyiduna Umar (may Allah be pleased with him). The narrator says: When he tasted it, he frowned, and he said: Indeed, the raisin nabidh of Ta'if is strong. Then he called for water, poured it in, and drank it. And he said: When nabidh seems strong to any of you, pour water into it and drink it.