Hadithcore
Mishkat al-Masabih, 3640

Abu Qatada told that the Prophet (ﷺ) forbade mixing dried dates and unripe dates, mixing raisins and dried dates, and mixing dates beginning to take on colour and fresh dates, and told them to make <i>nabidh</i> from each separately. Muslim transmitted it.

وَعَنْ أَبِي قَتَادَةَ: أَنَّ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ نَهَى عَنْ خَلِيطِ التَّمْرِ وَالْبُسْرِ وَعَنْ خَلِيطِ الزَّبِيبِ وَالتَّمْرِ وَعَنْ خَلِيطِ الزَّهْوِ وَالرُّطَبِ. وَقَالَ: «انْتَبِذُوا كُلَّ وَاحِدٍ عَلَى حِدَةٍ» . رَوَاهُ مُسلم

References1 variant
In-Book Reference
Book 17, Hadith 77