Authors : R.K. Majumdar, G. Venkateshwarlu and A.K. Roy
Abstract: A formulation containing fish, rice, corn and soyabean flour was extruded using a co-rotating twin-screw extruder. A (3x2x2) factorial design layout was used for this experiment to study the effects of extrusion conditions such as screw speed (350, 425, 500 rpm), barrel temperature (100, 120°C) and die diameter (3, 3.5 mm) as independent variables on the physical properties of extrudates, i.e., dependent variables expansion index and bulk density. Analysis of Variance (ANOVA) was carried to study the effects of main factors and interaction effects of various factors and multiple regression analysis was carried out to explain the variability. Neither main factors nor two factors interaction effect on expansion index were found to be statistically significant. Whereas in case of bulk density, all the main factors (temperature, screw speed and die diameter) and interaction effect (r x t) are found to be statistically significant. From the multiple regression analysis, R2 value was found to be 0.872 and 0.996, respectively for expansion index and bulk density. It was revealed from this study that independent variables significantly affected the physical properties of extrudates. From the treatment means for different treatment conditions, it was found that at a temperature of 120°C with screw speed 350 rpm showed least bulk density of 0.29 g cm-3.
R.K. Majumdar, G. Venkateshwarlu and A.K. Roy, 2011. Effect of Extrusion Variables on the Physico-Chemical Properties of Soyabean-Fish Based Ready-to-Eat Snacks. Agricultural Journal, 6: 23-27.