Effect of thermal treatments on functional properties of cress seed (Lepidium sativum) and xanthan gums: A comparative study

Foods are generally subjected to thermal treatments during processing operations, which affect on the functional properties of hydrocolloid solutions. In this paper, the effect of different thermal conditions (60 degrees C-30 min, 80 degrees C-23 min, 100 degrees C-18 min and 121 degrees C-15 min) on functional properties (rheological, emulsifying and foaming properties) of cress seed gum and xanthan gum were investigated. The results demonstrated that cress seed gum solutions had desirable rheological, emulsifying and foaming properties. When the hydrocolloid samples were heated, an irreversible increase in viscosity of cress seed gum solutions was observed and as a result, the emulsification and foaming properties improved. Whereas, xanthan gum would not have the ability to stand against heat treatment and its viscosity decreased. Nevertheless, the viscosity values of xanthan gum solutions were always higher than cress seed gum in all conditions. (C) 2011 Elsevier Ltd. All rights reserved.