Optimization of Lentil-Supplemented Salad Dressings as Affected by Type and Level of Hydrocolloids by Response Surface Methodology

Abstract

Background: Studies on the nutritional and health benefits of pulses have stimulated interest in using whole pulses and pulse fractions in novel value-added food products. In this study the effects of using different types and concentrations of gums (including xanthan gum [XG], mixtures of XG and gum arabic [GA], XG and propylene glycol alginate [PGA], XG and pectin [PE], and XG and guar gum [GG]) on the physical properties (i.e., rheology, texture, color and particle size distribution) of lentil flour-supplemented (3.5 w/w%) salad dressings were systematically examined. Response surface methodology was used to study the main effect of the two independent variables (x1, oil concentration; x2, gum concentration) on the generated responses and to optimize emulsion composition using commercial salad dressing parameters as reference. Results: An increase in both gum and oil concentrations enhanced emulsion firmness and viscosity by contributing to a more compact networked structure in the emulsion. Large droplets formed in the presence of higher gum concentrations at lower oil content. Color characteristics were affected to different extents depending on type and concentration of gum. Conclusion: The validation test showed overall adequacy of the final response surface models employed to predict properties of the lentil-supplemented salad dressing formulations.