مشخصات پژوهش

Microwave drying is a suitable technology to be prac-ticed in different industries. In addition to the short drying time, the process tends to preserve the nutri-tional values of agri-food products. In the present work, mass transfer characteristics of zucchini and carrot under microwave drying were investigated. The samples with thicknesses of 3, 5, 7 and 9 mm were dehydrated by practicing different microwave power levels (100, 350, 550 and 750 W). The results showed that moisture removal from the slices occurred in a short accelerating period at the process beginning followed by a falling rate period. The moisture diffu-sivity increased with both increasing microwave power and the samples thickness where the average values for zucchini and carrot slices changed from 1.17×10-8 to 9.42×10-8 and from 0.73×10-8 to 5.51×10-8 m2 s-1, respectively. The average activation energy for zucchini and carrot slices varied in the range of 1.22–1.68 and 1.57–1.84 W g-1, respectively and de-creased with increasing samples thickness