Modeling the Electrical Conductivity of Recombined Milk by Response Surface Methodology

Milk is the only known substance in nature that can provide the body with complete and balanced nutrition. Recombined milk is a milk replacement product. Recombined milk components are more easily adjustable than milk components. Using electrical conductivity, valuable information is available about the quality of different materials, including food. In addition, by this method, as a simple and practical tool, the quality of many foods can be controlled. In this study, Response Surface Methodology (RSM) was used for modeling and optimization of the electrical conductivity of recombined milk. The effects of protein (1, 2, 3, 4 and 5%), Lactose (4, 6, 8, 10 and 12%), fat (3 and 6%) and temperature (50, 55, 60, 65 and 70ºC) independent variables on electrical conductivity of recombined milk as dependent variables (response) were evaluated. Process variables were statistically significant (p<0.01) as quadratic regression model for this response. The R2 factor for the modeling of the electrical conductivity of Recombined milk was 0.92 by the response surface method. Optimum conditions for the electrical conductivity of the Recombined milk in the usual range (4 to 5.5 mS/cm) contained protein 3.4%, lactose 7.7%, fat 3% and temperature of 63.9 °C.