Optimization of process variables for the preparation of almond gum incorporated set-yogurt using Box-Behnken response surface model

The purpose of the current study was to optimize the formulation of almond gum incorporated set-yogurt with better functional and sensory attributes. The impact of almond gum concentration (0.05 – 0.2%), incubation time (5 – 8 h) and culture level (0.03 – 0.05%) was investigated on pH, water holding capacity (WHC), titratable acidity (TTA), syneresis and firmness of the prepared yogurt using response surface methodology (RSM). The models were found to be highly significant (p < 0.05). The high value of R2 for pH (0.9553), TTA (0.9277), syneresis (0.9943), WHC (0.9688), and firmness (0.9309) indicated that response surface second order polynomial models were adequate and valid. The optimum values of independent variables were 0.148g gum concentration, 7.678 h incubation time and 0.037g culture level for obtaining maximum WHC, minimum syneresis and optimum pH (4.4), TTA (0.7) and firmness (248) in the optimized yogurt. Overall acceptability and antioxidant activity of the optimized almond gum yogurt was significantly (p < 0.05) higher than the control yogurt.