Determination of Processing Quality Tests of Full Fat Soybean Extruded at Three Temperatures and Correlation with Growth

Two studies were conducted to evaluate the correlation between growth performance of chicks fed full fat soybean (FFSB) extruded at 145, 155 and o 165 and laboratory quality tests. In biological study, one hundred and forty four d-old male broiler chicks were divided into 12 groups including 3 treatments with 4 replicates of 12 chicks each and fed three diets containing 15 % FFSB extruded at 145, 155 and 165 o C from 0 to 21 d of age. Feed intake (FI), weight gain (WG) and feed conversion ratio (FCR) of chicks were not affected with increasing FFSB extrusion temperatures during 0-21 d of age. For evaluation the quality tests, the urea activity index (UA) was obtained as 0.11, 0.09 and 0.05 for FFSB extruded at 145, 155 and 165 °C, respectively. The correlation between UA with WG and FCR of chicks were 88 and 85 percent, respectively. The protein solubility in KOH (PSKOH) of FFSB extruded at 145, 155 and 165 °C, were 80.2, 78.1 and 72.4, respectively. The correlation between PSKOH with WG and FCR of chicks were 81and 88 percent, respectively. The protein dispersibility index (PDI) were 21.5, 20.8 and 16.5 for FFSB extruded at 145, 155 and 165 °C, respectively. The correlation of PDI with WG and FCR of chicks were 92 and 89 percent, respectively. It is concluded that the laboratory quality tests of FFSB were extruded at 145, 155 and 165 °C were in optimum range for broiler nutrition. Also the PDI had higher correlation with growth rate of chickens as compared to UA and PSKOH and could be the best quality index for estimating the growth rate of broiler chickens fed EFFSB