Messenger of Allah ﷺ prohibited us that we should mix dry dates with unripe dates or (mix) grapes with dry dates (and prepare Nabidh). He also said: He who amongst you drinks-the rest of the hadith is the same.
نَهَانَا رَسُولُ اللَّهِ ﷺ أَنْ نَخْلِطَ بُسْرًا بِتَمْرٍ أَوْ زَبِيبًا بِتَمْرٍ أَوْ زَبِيبًا بِبُسْرٍ وَقَالَ مَنْ شَرِبَهُ مِنْكُمْ فَذَكَرَ بِمِثْلِ حَدِيثِ وَكِيعٍ