Optimization of Enzymatic Production Process of Oat Milk Using Response Surface Methodology

Abstract

The simultaneous effects of slurry concentration (25–35 % w/w), enzyme concentration (0.5–2.5 % w/w) and liquefaction time (30–90 min) on the yield, total solids and rheological parameters of oat milk developed were studied and optimised by the application of response surface methodology. The effect of independent and dependent variables have been studied using a central composite rotatable design of experiments. Power law model explains the flow behaviour of the developed oat milk samples with correlation coefficient (R 2) varying from 0.89 to 0.96. All the formulations exhibited pseudo plastic behaviour with the flow behaviour index (n) between 0.29 and 0.46 and consistency index varying from 1.033 to 10.22 Pa s n . Statistical analysis showed that yield, total solids and rheology of oat milk were significantly (p < 0.05) correlated to slurry concentration, enzyme concentration and liquefaction time. The optimum conditions for making oat milk were: 27.1 % w/w slurry concentration, 2.1 % w/w enzyme concentration and liquefaction time of 49 min.