EFFECT OF HEAT TREATMENT ON THE RHEOLOGICAL PROPERTIES AND COLOR OF PUMPKINS (Cucurbita moschate)

摘要

B.CEPPA, Curitiba, v. 33, n. 1, p. 87-97, jan./jun. 2015EFFECT OF HEAT TREATMENT ON THE RHEOLOGICALPROPERTIES AND COLOR OF PUMPKINS (Cucurbitamoschate)Keila de Souza Silva*Carolina Castilho Garcia**Javier Telis Romero***Maria Aparecida Mauro****The aim is to investigate the eff ects of stepwise blanching and itscombination with drying on rheological properties and change ofcolor in pumpkins (Cucurbita moschata). 1 cm thick samples wereimmersed in water at 55 °C for diff erent times, followed by diff erentholding times prior to inactivation of the enzyme (97 °C/5minutes).Controled samples were obtained after blanching at 97 °C for 5minutes. The texture and color of the samples were measured and therheological parameters calculated according to the Maxwell model.The results showed that stepwise blanching for 40 minutes with 30minutes of holding time provided samples with equilibrium modulusof elasticity greater than the control samples. These parameterswere used as blanching pre-treatment to convective drying with airat 60 °C and a velocity of 1.5 m/s for diff erent drying times. Stepwiseblanched samples showed fi rmer tissues than control samples afterdrying. There were no signifi cant diff erences in the lightness andredness of stepwise blanched samples and control samples duringdrying.