The Book of Drinks (Kitab Al-Ashriba)

Muslim :: Book 23 : Hadith 4904

Abu Qatada, on the authority of his father, reported Allah's Messenger (may peace be upon him) having said this: Do not prepare Nabidh by mixing nearly ripe dates and fresh dates together, and do not prepare Nabidh by mixing grapes and dates together, but prepare Nabidh from each (one of them) separately.

Source materials are from the University of Southern California MSA site
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