Study On Physical And Chemical Properties Of Coarse Cereals Blended Rice Based On Hulless Barley

Ranking high in nutritional value and one of the best cereal products, hulless barley can be a welcome food molecule in contemporary dietary structrue, while its incomprehensive processing and application remains top critical problem. As extrusion technongy is being widely applied owing to its unique features as high material utilization ratio, small broad adaptability and little nutrition loss, it plays an important role in enlarging crop processing and having coarse cereal turned into staple food. This thesis studied extruded rice mainly made up of huless barley, with corn, millet, buckwheat added, according to the different distribution, quality properties of coarse cereals blended rice were analysised and the key indexes which influenced coarse cereals blended rice were screened out. In that way the optimum meters in belnded cereal manufacturing are confirmed. The results show that:(1)Blending certain proportion of corn flour, millet flour, buckwheat flour with highland barley, nutritional quality of blended rice could be improved, with additional corn flour and millet flour, the colour of blended rice reveals bright yellow and this might make it popular among consumers. Compared with 100% hulless barley rice, the elastic, cohesiveness, resilience and cooking loss ratio of the rice with millet flour added to were higher, glue viscosity, chewiness and cooking inflation ratio were higher than 100% hulless barley. When huless barley flour was blended with millet flour, the cooking quality and structure quality of the production were better.(2)According to the result of factor analysis, key indicators of belended rice quality properties were gelatinization degree, water absorption, water solubility, glue viscosity, hardness, chewiness, ash content, fat content and amylose content. By cluster analysis to classify different ratio of coarse cereals blended rice, the sensory quality and cooking quality of 100% hulless barley, 25% corn+75% hulless barley and 50% millet+50% highland barley were excellent, and the outcome were basically identical with the results of comprehensive scores.(3)Comparing with crop products, the gelatinization degree, water-soluble sugar and water imbibition increased significantly after extrusion; the improvement in 100% hulless barley rice wasnot shown in other two series of samples, the water solubility of other coarse cereals blended rice went down; after extrusion, resistant starch, soluble protein, NSI reduced significantly, the initial pasting temperature, peak viscosity, back to rise and the breakdown markedly decreased as well. The results indicated that, by extrusion, the absorption and utilization of coarse cereals blended rice were improved.(4)According to the adjusted extrusion parameters, namely, 25% material moisture, screw speed of 150 rpm, extrusion temperature at 150 ℃, feeding speed of 16 kg/h poilt production, the cooking quality of 50% millet+50% hulless barley was similar to japonica rice and structure quality similar to indica rice, which meant the closest to the quality standerd of ordinary rice.