Vacuum drying of carrot (Daucus carota) and pumpkin (Cucurbita maxima) : a study of the characteristics of the process / Secagem a vacuo de cenoura (Daucus carota) e abobora (Cucurbita maxima) : estudo das caracteristicas do processo

AUTOR(ES)
DATA DE PUBLICAÇÃO

2003

RESUMO

In this work it was studied experimentally the kinetics of carrot and pumpkin under vacuum drying in nature and pre-treatment by freezing and bleaching. The experimental runs were driven in a dryer under vacuum, at pressures of 5, 15 and 25 kPa and temperatures of 50,60 and 70oe. The influences on the drying kinetics of the pressures and temperature were studied, as well as effect of adopting pre-treatment. It was observed that the best values were obtained at the temperature of 70oe and pressure of 5 kPa for the samples pretreatment by freezing. As concerns to the raw material employed pumpkin presented higher drying speeds than the one shown by carrot, independently of the treatment received and of the operational condition of drying. The experimental curves of drying were adjusted to the difusional model of Fick for an infinite slab with or without shrinkage. The values of effective diffusivity obtained by considering the samples shrinkage were smaller than those calculated without considering this phenomenon

ASSUNTO(S)

abobora vacuo drying vacuum secagem pumpkin cenoura carrot

ACESSO AO ARTIGO

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