Comportamento higroscópico do suco de laranja liofilizado / Higroscopic behavior of freeze-dried orange juice

AUTOR(ES)
DATA DE PUBLICAÇÃO

1990

RESUMO

The higroscopic behavior of freeze-dried orange juice, with added maltodextrins and lactose and mechanical mixtures with this additives was studied through the kinetics and isoterms of water sorption in different temperatures. It was evaluated the spectral characteristics, in the visible and ultraviolet range, and the vitamin C content from samples of freeze-dried orange juice exposed at different relative humidities and temperatures. It was studied the influence of pH and buffer composition, on the limonene retention of freeze-dried emulsions. The spectral characteristics and vitamin C content showed no alterations after liofilization the maltodextrin (9-12 % dextrose equivalent monomolecular value increased. Freezedried lactose was amorphous. The equilibrium humidity content of the samples with additives were reduced when compared with mechanical mixtures. The additives also reduced the rate of water sorption. The limonene retention during freeze-drying was influenced by the initial concentration of the emulsion. The greater concentration studied showed the lower retention value.

ASSUNTO(S)

spectral characterization bebidas suco de laranja liofilizado retenção de cor temperatura de colapso estrutural retenção de vitamina c vitamin c retention freeze-dried orange juice water sorption isotherms color retention isotermas de sorção de umidade caraterização espectral strucutral collapse temperature

ACESSO AO ARTIGO

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