Hydrocolloid stabilizers have the potential to produce high viscosity products at low concentrations. Due to their unique functionalities these products are widely used in food process industry. In current research the effects of different concentrations of Glucomannan Konjac (different levels of 0.2, 0.4, 0.6%) were evaluated on physical properties including pH, acidity, fat, total solids and melting resistance, sensorial characteristics and rheological properties of ice cream including flow behaviour and fitting with famous rheological models. The results revealed that viscosity, total solids and melting properties had direct relation with konjac substitution level. All substitution levels lead in significant increase in viscosity. The lowest resistance to melting and the highest total solid contents was related to the highest konjac concentration. Consistency coefficient increased and flow index behaviour decreased, With increasing konjac level up to 0.6%. Power law and Herschel-Bulkley models were successfully fitted with the rheological parameters. Yield stress significantly increased with increasing level of stabilizer. These improvement in rheological behaviour is attributed to the presence of high molecular weight components that have the potential to maintain water. Control sample gained the lowest score in sensorial evaluations.

Keywords: Konjac Hydrocolloid, Ice cream, Consistency coefficient, Flow index behaviour

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