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Orientador(es)
Resumo(s)
The effects of water blanching, freezing, and frozen storage during 400 days at three different temperatures ( 7, 15 and 30 C), on watercress (Nasturtium officinale R. Br.) colour Hunter Lab parameters,chlorophyll degradation, vitamin C content loss and peroxidase (POD) activity were evaluated. The blanching induced significant changes on colour values and chlorophylls and vitamin C contents. POD
activity was reduced 85% from its initial value. Freezing did not affect chlorophylls and vitamin C levels, however, promoted significant differences in colour values and POD residual activity. During frozen storage,
ascorbic acid (AA) and POD activity Degradations followed first-order kinetics, and colour parameters (LH aH bH, aH/bH, LH aH/bH, LH/aH bH and hue (h0
H)) were successfully described by zero-order kinetics. The storage temperature effect was successfully described by the Arrhenius law. Chlorophylls and dehydroascorbic
acid (DHAA) contents were kept constant during frozen storage.
Descrição
Palavras-chave
Frozen watercress Quality parameters Peroxidase activity Kinetics
Contexto Educativo
Citação
"Journal of Food Engineering". ISSN 0260-8774. 93: 1 (2009) 32–39
Editora
Elsevier