Enrichment of Rice with Grape Peel Powder by Extrusion

Abstract

 —Following the tendency to reduce food loss and contributing with environment sustainability, generating value-added utilizing food industry residues, this research aims thetechnological characterization of grape byproductand rice extruded flour. The physical behavior of rice (Oryza sativa L.) and grape peel (Vitis vinifera L.) extruded flours were investigated. A range of grape peel (15 25%, screw speed (100 150 rpm) and moisture content (18 26%) were studied. The aim of this study was to evaluate the effect of extrusion cooking process in a grape peel powder and the white rice flour addition. The results of bulk density was between 270 and 566 kg/m; sectional expansion ratio was 2.42 to 6.51; longitudinal expansion ration was 0.58 to 0.96; volumetric expansion ratio was 2.15 to 4.64; water solubility index was 7.60 to 15.57; water absorption index was 4.35 to 6.82. Results of instrumental color was measured and the range of L* was 26.38 to 37.68; a* was 11.70 to 14.56 and b* was 3.78 to 7.42. The grape peel addiction on extrudates increased the bulk density and longitudinal expansion index. However, decreased on sectional expansion index, volumetric expansion index, water solubility index, water absorption index and luminosity. Results obtained with conditions processing demonstrated the incorporation of grape peel in rice is