Musannaf Ibn Abi Shayba 13:739

Abu Bakr narrated to us, he said: Waki’ narrated to us, from Malik ibn Anas, from Abdullah ibn Yazid, from Zayd Abu Ayyash, who said: I asked Sa’d about [exchanging] barley for corn, and he disliked it. He said: The Messenger of Allah (may Allah bless him and grant him peace) was asked about [exchanging] fresh dates for dried dates. He said: "Does it decrease when it dries?" They said: "Yes." So he disliked it.