Résumé :
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Ripe banana, cut to 10 mm thick slabs were osmotically treated in sugar solutions of 35, 50 and 65 degrees Brix for 36 h. The initial moisture content fell from a value of 3.13 kg H2O DM to 2.19, 1.63 and 1.16 kg H2O kg(-1) for treatment in the three solutions, respectively. These slabs, with Total Soluble Solids (TSS) contents of 26, 34 and 39 degrees Brix, respectively, as well as freshly cut but untreated slabs (15 degrees Brix) were air dried in a cabinet type tray drier to near equilibrium conditions at fixed temperatures from 40 to 80 degrees C and at a constant air speed of 0.62 m s(-1). Drying was found to occur in the falling rate period only for both banana types and two drying constants K-1 and K-2 were established for a first and second falling rate period of drying. Increasing the drying air temperature significantly enhanced the drying rate and the K-values, except at 80°C when the rates fell, possibly because of case hardening of the slabs.
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