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Resumen:
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The effect of the sucrose solution concentration on the process kinetics and yield during osmotic dehydration of mango (Kent var.) cylinders has been studied. Processes were carried out at 30 ºC, using 35, 45, 55 and 65 ºBrix sucrose, at atmospheric pressure (osmotic dehydration) and by applying a vacuum pulse (50 mbar for 10 min) at the beginning of the process (pulsed vacuum osmotic dehydration, PVOD). Kinetics of sugar gain, and water loss, as well as changes in sample mass and volume was analysed. Effective diffusion coefficients in the fruit liquid phase were also estimated. Microstructure of the mango samples after 15 min of PVOD treatments were examined by scanning electron microscopy. Effective diffusion coefficient in the fruit liquid phase increased when sucrose concentration decreased and was always higher in pulsed vacuum osmotic processes. These give rise to tissue impregnation with sucrose solution to an exceptional extent for the treatment with 45 ºBrix, which induces a very high sugar gain-water loss ratio.
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