Determining and modeling rheological characteristics of quince seed gum

In this research, rheological characteristics of quince seed gum were investigated. To describe shear thinning behavior, Cross model with high determination coefficient (R2) and low root mean square deviation (RMSE) was applied at shear rate of 0.01–1000 (s−1) and concentration range of 0.01–0.7 (%, w/w). Using Arrhenius model, activation energy was estimated to be 6988.74 J mol−1in the gum solution (0.3%) and temperature range of 25–55 °C. Linear viscoelastic range of the gum solution (0.3%, w/w) in the presence and absence of 0.2 M NaCl was measured as 11.4% and 7.7%, respectively. Loss and storage moduli of the gum solution (0.3%, w/w) at frequencies of 0.01–100 (Hz) showed that, at all of these frequencies, storage modulus was more than loss modulus and both of them increased with increase of frequency. Critical polymer concentration (C∗) was determined as 0.077 g 100 ml−1 through slopes of the lines for dilute and semi-dilute regions in concentration range of 0.01–0.7 (%, w/w). Capillary viscometer determined intrinsic viscosity and Huggins constant of quince seed gum as 1530 ml/g and 0.32, respectively.