From Sahih Bukhari (Hadith 5622):
Narrated Anas:I was waiting on my uncles, serving them with an alcoholic drink prepared from dates, and I was the youngest of them. (Suddenly) it was said that alcoholic drinks had been prohibited. So they said (to me), 'Throw it away." And I threw it away The sub-narrator said: I asked Anas what their drink was (made from), He replied, "(From) ripe dates and unripe dates
Reference: Bukhari 5622