Understanding The Structure And Quality Of Rice Noodles Subjected To Extrusion Processing Conditions

Decades of economic development have caused dietary structure changes in modern society.The incidence of metabolic diseases,obesity,diabetes,and cardiovascular disease is found to be increasing recently.The development of nutritious,healthy foods,or the improvement of human health by improving the nutritional properties of traditional foods has received much attention.At present,the fluctuation of blood sugar levels caused by rice and rice noodle products due to the rapid digestion rate is the primary concern to the consumer.The application of extrusion processing in rice products only focuses on the influence of processing parameters on the structure and quality of rice products,while not systematically analyzing the influence of raw materials and components interactions on rice products.In this paper,processing method using a twin-screw coupling exogenous extruded rice protein,with the main goal of regulating the digestibility of rice noodles products,and taking into account the basic quality,the suitability of rice starch was characterized.Investigate the effect of exogenous rice protein and extrusion parameters on the ordered structure and basic quality of rice starch-protein complex and rice noodles products.Provide a reference for the regulation of new healthy rice products.Differences in amylose content,morphology,chain length distribution,short-range ordered structure,and crystal structure in different rice starches investigated with the combination of fluorescence-assisted capillary electrophoresis,gel permeation chromatography,infrared spectroscopy,and other modern instrumental analysis technology.In order to further improve the product value of rice noodles products,the rheological properties and gel texture properties of starch pastes with different amylose content were studied.The results found that waxy rice starch has a large proportion of medium and long chain,and the short-range order is stronger and the relative crystallinity is larger.Japonica rice starch has more short chains.Waxy rice starch,Japonica rice starch and Indica rice starch paste are yielding pseudoplastic fluids,and Indica rice starch paste exhibits stronger shear thinning characteristics.Indica rice starch gel having greater strength.Finally,we recommend that Indica rice is suitable as raw material for high-quality rice noodles products.By changing the extrusion processing parameters such as exogenous protein content,material moisture content,screw speed,barrel temperature and aging time,Effects of various parameters on the structural quality changes of rice starch-rice protein complex were investigated.This study showed that there is no new substance formed during extrusion processing.The crystal structure of rice starch is destroyed and the addition of rice protein promotes the V-type crystal during extrusion.As the screw speed increases,the increase of shear rate contributes to the polymerization between protein molecules and the gelatinization of starch molecules,which helps the extrusion system to form a more stable structure,which makes it difficult for digestive enzymes to contact with starch molecules.The recrystallization behavior of starch molecules during aging enhances the structure of the complex and has a certain inhibitory effect on the dissolution of starch molecules.After the addition of rice protein,the extrusion process has a significant effect on the crystal structure,digestibility and cooking characteristics of rice starch.Thereby,the basic quality characteristics of the rice starch product can be adjusted by increasing the exogenous rice protein.Indica rice used as the raw material,a suitable amount of exogenous protein,Prepared rice noodles products by changing the processing parameters such as moisture content,screw speed,barrel temperature,aging time,etc.Compared with commercially available rice noodle products,exploring the suitable process conditions for the preparation of rice noodles products by twin-screw extrusion coupled with exogenous rice protein.The study found that extrusion temperature directly impacts breakage of rice,starch gelatinization and melting,and the compounding process,and the rice noodles products with lower digestibility can be obtained under moderate screw speed.Prolonged aging time can reduce the RDS content in rice noodles products.The optimum processing conditions of rice noodles products: Indica rice,rice protein content of 10%,moisture content of 38%,screw speed of 50 rpm or 60 rpm,barrel temperature of 95°C or 100°C,aging about 24 h,and the rice noodle products obtained under the above conditions,Its cooking loss,water absorption performance,expansion performance and texture characteristics can reach desired level.In this paper,the effects of raw materials,twin-screw extrusion coupled with exogenous rice protein on the microstructure,digestive properties and quality characteristics of rice noodle products were researched.A suitable extrusion process for optimizing the slow digestion/antidigestibility and basic quality characteristics of the rice noodle product is obtained.It provides a basic basis for better realizing the nutritional quality of rice processing products such as traditional rice noodle products and expanding the rational application of new processing technologies.