Optimization of the Spreadable Modified Butter Manufacturing by Response Surface Methodology

The aim of this study was to optimize the manufacturing condition of spreadable modified butter by RSM. Based on the central composite design, the degree of optimization was expressed as a SFC as a dependent variable (Y, %) determined by NMR with 23 experimental groups. Three independent variables were the contents of butter (X1, 35-75%), the contents of grape seed oil (X2, 15-35%), and the contents of hydrogenated soybean oil (X3, 0-4%). As the result, SFC at 10oC was ranged from 32.37 to 42.76%. In addition, the regression coefficients were calculated for SFC at 10oC by RSREG. The regression model equation for the SFC was Y=39.18-0.04X1X3. Consequently, the optimal contents for manufacturing spreadable modified butter were determined as 55.18% for butter, 40.78% for grape seed oil, and 4.08% for hydrogenated soybean oil, respectively. The predicted response value for SFC at 10oC was 30.20%, comparable to the actual experimental SFC value as 29.85%. Finally hardness and spreadability in reference butter and spreadable modified butter produced under the optimal conditions was measured. The hardness in spreadable modified butter was 31.80 N as compared to 69.92 N in reference butter. The spreadability in spreadable modified butter was 5.6 point as compared to reference butter. This difference may be due to the contents of solid fat by butter and hydrogenated soybean oil. This study showed that the SFC value at 10oC could be a suitable indicator for the manufacturing spreadable modified butter to predict important attributes such as mouth feel, hardness and spreadability.