RHEOLOGICAL PROPERTIES OF STRAWBERRY PUREE JAM

Abstract

The rheological properties of strawberry puree jam as a sample of some food gels investigated using Brookfield rotational viscometer at different temperatures (30, 40, 50, 60 and 70°C) and different solid concentration of 40, 45, 50, 55 and 63 %. The investigated samples exhibited non-Newtonian pseudoplastic behaviour and fitted well to the power law model. The effect of concentration on the apparent viscosity was studied and fitted well to power law equation. The results observed that the apparent viscosity is exponentially proportional with the concentration of strawberry puree jam at all temperatures studied. The effect of temperature on the apparent viscosity of strawberry puree jam was fitted well to Arrhenius law; activation energy was 25.26 – 97.78 kJ/mol.