Optimization of antioxidant activity and sensory parameters of millet egg tofu using mixture design

Abstract

Optimizing three millet milk, namely barnyard, foxtail, and little millet, was done to develop millet egg tofu using a mixture design. The color values (L*, a*, and b*), texture value (hardness), total phenolic content, scavenging activity 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power assay (FRAP), and sensory parameters (appearance, color, flavor, taste, texture, and overall acceptability) were observed to study the effect of these millets on the millet egg tofu. Results revealed that a significant (p < .05) rise in the lightness value and significant (p < .05) reduction in the hardness was observed in the millet egg tofu prepared using a combination of barnyard, foxtail, and little millet milk. Significantly (p < .01) increased total phenolic content was observed in the millet egg tofu prepared with barnyard, foxtail, and little millet milk, higher DPPH in little millet milk, and higher FRAP values in the combination of foxtail and little millet, but lower acceptability scores. The optimum formulations for the millet egg tofu were attained using overlay plots related to hardness and sensory parameters (appearance, color, taste, and overall acceptability) generated the yellow region based on the optimum value. The outcome revealed that the optimum values for the predicted responses were 4.08 N, 5.97, 5.91, 5.61, and 6.05 for the hardness, appearance, color, taste, and overall acceptability, respectively, which were obtained from the optimum combination of 2.3% barnyard millet milk, 2.41% foxtail millet milk, and 20.36% little millet milk. Novelty impact statement Barnyard, foxtail, and little millet milk is new ingredient in egg tofu formulation. This millet egg tofu has good sensory properties. The millet egg tofu produced with barnyard, foxtail, and little millet milk is a fiber-rich functional food targeted to help in controlling and managing diabetes and obesity.