Determining the optimum temperature for dry extrusion of full-fat soyabeans

Full-fat soyabeans (FFSB) intended for use in monogastric nutrition need to undergo heat treatment so that present anti-nutritional factors can be inactivated. Under- or over-treatment will decrease the level of amino acids available to the animal. In this study, the slope-ratio technique was used in two trials with broilers for determining the optimum treatment temperature for soyabeans. Average daily weight gain (ADWG) and feed conversion efficiency (FCE) were used as response parameters. The optimum temperature for dry extrusion of FFSB was 144 °C for Trial 1 and 138 °C for Trial 2. Similar temperature values were generated by both ADWG and FCE. Either one can therefore be used as response parameter for determining the optimal heat treatment conditions of FFSB for use in poultry feeding.