Investigation of Rheological Behavior of Malva Flower Mucilage Under Different Temperature, Concentration and Shear Rate Conditions

Hydrocolloids, playing different roles including thickening, stabilizing, gelling and improving texture of foods are among additives widely used for improvement of quality in food industry. Recently, demand for hydrocolloids with special functional properties has grown, therefore, finding new sources of gums with proper attributes is of enormous importance. Therefore, this study aimed at investigating the effect of variables including temperature (30-80°C), concentration (5-9%) and shear rate (0.1-1000 s-1) on apparent viscosity and flow behavior of malva flower mucilage solution. The results showed that malva flower mucilage was rheologically pseudoplastic with this behavior being enhanced at higher concentrations (<n). The effect of temperature and concentration on flow index and consistency coefficient was also significant (p≤0.05). At low concentrations, power law model and at high concentrations, casson and bingham models best fitted with mucilage solution. Also mucilage solution at 5% and 9% concentrations showed the lowest and the highest temperature dependency, respectively.