Effect of Defatted Rice Bran Addition on Properties of Texturized Soy Protein Products

Abstract

The objective of this work was to develop low moisture-texturized vegetable protein (LM-TVP) using defatted rice bran (DRB) and soy protein isolate (SPI) as raw materials. The effect of DRB addition on properties of texturized soy protein (TSP) was studied. TSP samples were prepared by blending SPI: DRB at ratio of 45:55, 60:40 and 75:25 (w/w) to produce TSP with 50, 60 and 70% protein, respectively. Then, all samples were extruded using twin screw extruder. Extrusion condition was fixed at 25% of feed moisture, 400 rpm of screw speed and 130 °C of die temperature. Next, properties of TSP50-70 before and after rehydration were characterized. The results showed that the expansion ratio and density of TSP50-70 were in range of 2.03-2.57 and 0.19-0.29 kg/m3, respectively. After rehydration the water absorption capacity, water holding capacity and oil holding capacity of TSP50-70 were in the same range which were 390-430%, 4.62-4.97 g water g-1, 2.9-3.3 g oil g-1, respectively. However, there was a significant difference in texture between TSP50 and TSP70. Decreasing DRB content from 45 (TSP50) to 25% (TSP70) increased springiness from 0.76 to 0.93, cohesiveness from 0.51 to 0.79 and hardness from 0.45 to 1.52 N of TSP samples. Compared to commercial TVP, all studied properties of TSP70 were in acceptable range. Therefore, to add value to DRB the TSP70 (75%SPI and 25%DRB) was proposed in this study to produce TVP with low beany odor.