To obtain an optimum formulation for stabilizers–emulsifier in ice cream, different combinations of three stabilizers, i.e. basil seed gum, guar gum, and carboxymethyl cellulose, at two concentrations of 0.15 or 0.35% with or without E471 emulsifier were studied using a simplex-centroid mixture design. The regression models for physical properties and texture smoothness of samples were also established. Generally, increasing ratios of basil seed gum in gums mixture increased the apparent viscosity of ice cream mixes and smoothness of texture, but decreased the melting rate. Increasing proportions of guar gum enhanced overrun of samples. Results suggested that the combination of 96.94% basil seed gum and 3.06% guar gum at the concentration of 0.35% with 0.15% emulsifier produced the optimum ice cream. Subsequently, the interaction of the obtained optimum formulation with κ-carrageenan as a secondary stabilizer was studied at two levels of 0.01 and 0.02%. The pH, draw temperature, overrun, hardness, and melting rate were measured through physical methods. Rheological and sensory analyses were also performed. Inclusion of κ-carrageenan in formulations decreased the values of instrumental hardness and improved the smoothness of the samples; while it had no significant effects on other properties such as draw temperature, overrun, sandiness, and foaminess.

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