DETERMINING THE DIFUSION CO-EFFICIENT OF RIPE AND SEMI-RIPE UMBU FRUITS (Spondias tuberosa, Arruda Câmara) DURING THE THIN DRYING LAYER

The present work has got as its aim to determine the co-efficient of umbu fruits diffusion whilst semi-ripe and ripe obtained from the thin drying curves made at temperature levels of 70, 80 and 90oC. The drying processes have been made in a experimental dryer with an initial moisture level of 81,52, and 83,18% wet basis, for semi-ripe and ripe umbu, respectively up to the final water rates of 40, 35, and 30%b.u.. The drying air speed was 1,27m.s -1 . In order to obtain the diffusion co-efficient, Fick’s equation was used for one sphere, one two and three terms of the series being used with a help of the non-linear regression program (Statistica version 5.0). Due to the obtained results, we could come into a conclusion that the diffusion co-efficient of Fick’s equation for ripe and semi-ripe umbu fruits increases along with the drying temperature, and whenever dada is placed according to temperature, they can be expressed by an Arrhenius-like equation.