Dilute Solution Properties of Nettle Seed (Urtica pilulifera) Gum as a Function of Temperature

This research focused on determining some molecular properties and intrinsic properties of Nettle seed gum (NSG), as one of the novels and natural sources of hydrocolloids, at different temperatures (10, 25, 40, 55, and 70°C) in the dilute region. The results showed that among the models studied, the Higiro 2 model with the highest R2 and lowest RMSE values was the most proper model for determining the intrinsic viscosity of the NSG. Based on this model, the intrinsic viscosity value of NSG was obtained in the range of 0.15–0.21 dl/g. It was also found that, as the temperature raised, the intrinsic viscosity of NSG declined. The shape factor of NSG at 40°C was spherical; however, increasing the temperature from 40°C to 70°C, it to an ellipsoidal shape. Berry number and master curve slope showed that NSG solution at all temperatures was within the dilute regime and that no molecular entanglements existed.The parameter b values acquired for NSG at the intended temperatures showed that the molecular conformation of NSG was the random coil. The activation energy and chain flexibility parameters calculated for NSG at the tested temperatures were 0.488×107 J/kgmol and 587.2, respectively.