“…In such unsteady-state situations the food concentration distribution varies with both time and position. Mass transfer under unsteady-state plays a key role in drying, freeze-drying (George & Datta, 2002), lixiviation, infusion, osmotic dehydration (Mauro, de Queiroz Tavares, & Menegalli, 2003;Moreira & Sereno, 2003;Sablani, Rahman, & AlSadeiri, 2002), salting or desalting, and frying processes. The transfer process of compounds from the packages into the food (Nobile, Fava, & Piergiovanni, 2002;Risbo, 2003), and controlled release of active compounds can also be considered as unsteady-state systems.…”