Is it permissible to trade raw produce for its cooked form of the same genus?
Chapter on Riba (Usury) and Exchange (Sarf)
Al-Mughni
Book of Sales
Primary text
The exchange of raw produce for its cooked form of the same genus is not permissible because the cooked item is inherently subject to a deficiency in a subsequent state (after the initial exchange), making the exchange invalid, analogous to trading fresh dates for dried dates (tamar).