PAPER Ital. J. Food Sci., vol. 27 - 2015 1 - Keywords: Microwave, air drying, antioxidant activity, total phenolic content, response surface methodology - OPTIMIZATION OF MICROWAVE AND AIR DRYING CONDITIONS OF QUINCE (CYDONIA OBLONGA, MILLER) USING RESPONSE SURFACE METHODOLOGY CEM BALTACIOG ˘ LU*, NURHAN USLU and MEHMET MUSA ÖZCAN Food Engineering Department, Faculty of Agriculture, Selcuk University, Konya, Turkey *Corresponding author: cembaltacioglu@gmail.com ABSTRACT Effects of slice thickness of quince (Cydonia oblonga Miller) , microwave incident power and air drying temperature on antioxidant activity and total phenolic content of quince were investigat- ed during drying in microwave and air drying. Optimum conditions were found to be: i) for mi- crowave drying, 285 W and 4.14 mm thick (maximum antioxidant activity) and 285 W and 6.85 mm thick (maximum total phenolic content), and ii) for air drying, 75 ºC and 1.2 mm thick (both maximum antioxidant activity and total phenolic content). Drying conditions were optimized by using the response surface methodology. 13 experiments were carried out considering incident microwave powers from 285 to 795 W, air temperature from 46 to 74 ºC and slice thickness from 1.2 to 6.8 mm.