Extrusion is one of food cooking methods in high temperatures for a short period of time. The ingredient will flow through channel under the influence of several processes such as mixing, heating, cutting, and dyeing to get a dry and puffy product. This method will prevent the food product from any nutritional damage and maintain its content from any potential harmful substances.
The aim of the research is to determine mathematical model of the impact by adding protein content substance in the mixture of garut flour and corn flour to the physical characteristics of extrudat. The second aim is to compare the physical characteristics obtained from instrumental test with the physical characteristics obtained from organoleptic (sensory) test. The third aim is to find the best composition in this research.
The mixture of garut flour and corn flour was made in four composition. Protein content substance such as skim milk powder, soy bean flour, and mung bean also was made in four composition. The total mass of each sample mixture is approximately 200 grams.
This research result shows that by adding protein content substance will affected the flow rate and mass flow of extrudat. However, it doesn’t give any obvious impact in other physical characteristics such as puffing, density, moisture content, strain, tension, and elasticity. Mathematical model used to describe the relationship between variation of the extrusion substances with the phisycal characteristics of extrudat is polynomial quadratic one. The other mathematic model obtained to describe the relationship between the physical characteristics resulted from instrumental test with ones from organoleptic test is the linear regression one.
