Microwave assisted drying of short-cut (ditalini) macaroni

ABSTRACT MICROWAVE ASSISTED DRYING OF SHORT-CUT (DITALINI) MACARONI ALTAN, Aylin M.Sc. in Food Engineering Supervisor: Assoc. Prof. Dr. Medeni MASKAN June 2003, 84 Pages Macaroni samples were dried by conventional hot air, microwave and hot air followed by microwave drying methods. The drying of macaroni samples took place in the falling rate period. Higher drying rates were observed with the higher microwave power levels. A model was employed to fit the experimental drying data and gave a good fit for all experimental runs except hot air-microwave (210 W) finish drying data. Drying only with microwave energy (70 W and 210 W) or hot air- microwave energy (70 W and 210 W) resulted in substantial shortening of the drying time (61.8%, 87.3%, 61% and 78%, respectively). The total drying time, the color, rehydration capacity and macaroni cooking quality, related to cooked weight, cooking loss and firmness were evaluated. The textural properties of uncooked and cooked macaroni samples were measured by using a TA-XT2i Texture Analyzer. Protein denaruration increased significantly as microwave power increased. Macaroni samples dried with combined hot air-microwave (210 W) was equal or better than hot air. Also, hot air-microwave combination drying exhibited superior cooking properties. Cooked weight and firmness increased while cooking loss decreased generally as microwave applied after hot air drying, i.e., hot air-microwave combination shortened the drying time and improved the physical, textural and cooking quality of macaroni samples. Key words: drying, macaroni, microwave, color, rehydration, cooking quality, texture. m