Effects Of Barley Varieties And Particle Size On The Quality Of Recombinant Flour Dough And Noodles

As a grain,the protein of highland barley flour can not form a gluten network structure,so it’s poorly processed,and it is necessaryto addother flour to grain flour to make dough.At present,the research on highland barley mainly focuses on-glucan extraction and physiological function,as well as a few innovative food technology and product development.Although there are some papers about the research on the compound flour products of highland barley,most of them focus on the content of highland barley powder,the development of product technology and the innovation of products,there are few reports about the effect of variety and particle size of highland barley on the dough and noodle,and there is no in-depth study on the effect of grain size on gluten formation and noodle quality.In view of this situation,highland barley was used asraw material inthis paper,and the mixture of highland barley powder,wheat powder and gluten protein powder in the proportion of 42.5%: 50%: 7.5% was knead with water to make dough,the influence and change rules of dough and noodles due to variety and grain size of highland barley were studied,in order to provide basis for processing of highland barley flour products.The main conclusions are as follows:(1)The rheological properties of the dough and the quality of noodles could be affected by the difference of chemical composition in highland barley,among which the effect of total starch and dietary fiber was the most significant.The flour properties and gelatinization properties of dough were mainly affected by total starch,dietary fiber andβ-glucan.The breaking rate,cooking time and water absorption of noodles were related to the total starch and dietary fiber of highland barley.Cooking loss was related to protein,total dietary fiber and β-glucan.Hardness,adhesion and breaking force were related to dietary fiber and β-glucan.In cooking,the quality of Zangqing 2000 and Kangqing 9 were the best,and the quality of Beiqing 8 and Zangqing 27 were the second.Texture and shear-tensile properties of Zangqing 8 were the best.The microstructure showed that the noodles of Beiqing 8,Zangqing 25 and Zangqing 27 had clear and regular structure,and the starch granulateswere evenly and orderly embedded in the network.The structure of Zangqing 2000 and Kangqing 9 wereso close and agglomeratethat network was not obvious,the starch granulesof QB14 were uneven in distribution,there were a lot of cell fragments and the network structure was so loose and porous.By comprehensive comparison,Beiqing 8 noodles had the best quality,it was the best processing type and the most suitable for making highland barley noodles,the second was Zangqing 27,the other varieties had poor processing ability.(2)The pasting and rheological properties of the dough,as well as noodles’ quality,could be affected bythe different particle size of highland barley powder,and the content of damaged starch increased with the particle size decreasing.With the decrease of the particle size,the peak viscosity,the through viscosity and the breakdown value of the dough increased gradually.The mixing properity showed that the water absorption of the dough increased gradually,the formation time decreased gradually,and the stable time increased first and then decreased,the stability of thermal gel was enhanced and the retrogradation value was decreased.For the reconstituted noodles,the cooking and textural quality of the coarsest size noodles were the worst(P<0.05),while the shearing force and tensile force of the other size noodles decreased with the decreasing of the particle size,but there was no significant difference between cooking and TPA.But the microstructure observation showed that the gluten network structure increased first and then decreased with the decrease of particle size,which was consistent with the stability time of dough.Therefore,the quality of highland barley noodles was the best when the grain size of highland barley was controlled from 42.33 μm to 90.73 μm.(3)There were obvious differences in particle size,morphology and physical properties of starch and fiber extracted from whole highland barley powder with different grain sizes.By reducing the size of starch and fiber,increasing the content of damaged starch and destroying the inherent structure of fiber,crushing could change the water absorption,swelling,gelatinization,thermal properties of starch and the water holding capacity of fiber,and then lead to the changes of noodles’ texture,cooking properties and gluten protein structure.With the decrease of particle size,the hardness and chewability of reconstituted noodles decreased slightly,the broken sliver rate increased gradually,the shear force decreased,and the tensile force increased first and then decreased.In the fiber group,the optimum cooking time decreased and the cooking loss increased with the decrease of particle size.The results showed that the enthalpy of the starch group decreased gradually,while the fiber group increased gradually with thedecrease of grangules.It was found from microstructurethat the decrease of fiber and starch in particle size was beneficial to the formation of gluten network structure because of the more uniformity in distribution,so as to improve the noodles’ quality.