Optimization of Mango Soy Fortified Yogurt Formulation Using Response Surface Methodology

Abstract

The response surface methodology (RSM) was used to optimize the formulation of mango soy fortified yogurt (MSFY). The independent variables were proportions of mango pulp (1.2-13.8%), soymilk (2.39-27.61%), and fat content (0.48-5.52%) of buffalo milk. The responses were overall acceptability rating, counts of Streptococcus thermophilus and Lactobacillus bulgaricus and hardness of the product. Statistical analysis revealed that mango pulp, soymilk, and fat content of buffalo milk significantly affected (95% confidence level) all the responses. Contour plots for each response were used to generate an optimum area by superimposition. Model validation was conducted using separate experiments at optimum conditions. The optimum formulation conditions of 7.1 kg mango pulp (18% total solids), 14.7 kg soymilk (8.2% total solids), and 78.2 kg buffalo milk (2.95% fat content and 9% solid not fat) per 100 kg are recommended for the blend formulation yielding an acceptable and good quality MSFY.