Effect Of Alkaline Salts On Quality Characteristics Of Wheat Flour Noodles

In this paper,in order to investigate the effect of alkaline salts composed of sodium carbonate and potassium carbonate(with a fixed addition of wheat flour at 0.4% but diffierent sodium to potassium carbonate ratio at 1:0,0.8:0.2,0.6:0.4,0.4:0.6,0.2:0.8,0:1 and a fixed sodium to potassium carbonate ratio at 0.8:0.2 but different addition of0.1%,0.2%,0.4%,0.6%,0.8%,1.0%,1.2% reapectively)on wheat flour quality,noodle quality and properties of protein and starch in noodles.The property of gluten,farinograph and extensograph properties of doughs,the texture property,cooking property,protein and starch properties of noodles were texted.The main conclusions were as follows:(1)In the range of the experiment,alkaline salts with any compound ratio could increase the development time,water absorption,improving the processing performance of the three different kinds of wheat flour(ie Aikang 58,Xinong 979 and Zhongmai NO.2)doughs in different degree.With the addition of alkaline salts increasing,the water absorption of dough increased significantly(p < 0.05),and the optimum addition amount was 0.4%.Adding alkaline salts could increase the energy,resistance to extension,extension ratio and gluten index of dough,while reducing dough extensibility and dry,wet gluten content of wheat flour.(2)In the range of the experiment,alkaline salts with any compound ratio could increase the cooking loss of noodles of Aikang 58,Xinong 979 and Zhongmai NO.2significantly(p < 0.05),but the cohesion of the three kinds of wheat flour noodles did not change obviously,and the difference of springiness was not significant(p > 0.05).With the increase of potassium carbonate ratio in alkaline salts,the water absorption of noodles increased,the cooking loss decreased,and the springiness showed no significant change(p> 0.05).Any addition of alkaline salts could increase the cooking loss and had a certain effect on the hardness,adhesiveness,resilence,cohesion,gumminess and chewiness of noodles,but there was no significant difference in the springiness of noodles(p > 0.05).With the increase of alkaline salts addition,the water absorption of noodles increased and then decreased significantly(p < 0.05),reaching the maximum when the addition was 0.2%.The cooking loss of noodles increased significantly(p < 0.05).So the optimum ratio of alkaline salts was eight share of sodium carbonate and two share of potassium carbonate,and the optimum addition amount was 0.4%.The effect of alkaline salts on the maximum tensile force and tensile distance were not completely the same.(3)In the range of experiment,alkaline salts could increase the glutenin macropolymer content and increase the contents of albumin and salt-soluble protein in the three kinds of wheat flour noodles(p < 0.05)significantly,while the globulin content decreased significantly(p < 0.05).The contents of gliadin and glutenin decrease,but the gluten contents decreased significantly(p < 0.05),the effect on Glu/Gli was not consistent.The optical density of the low and middle molecular regions in the SDS-PAGE maps were increased whether the protein in the noodles was reduced by reductant or not,and this was consistent with the changes of albumin and globulin contents on the whole.No band of protein subunit is moved or missing.Sodium to potassium carbonate ratio at any ratio could promote the formation of an ordered network structure of noodles,making the internal structure of noodles more compact and uniform,the pores more uniform,starch particles were wrapped by the network structure more closely.potassium carbonate could improve the internal structure of noodles better than sodium carbonate,and when the amount of alkaline salts was 0.6%,the internal structure of noodles reached the best state.(4)While alkaline salts had influence on the peak viscosity,minimum viscosity,breakdown,final viscosity,setback,peak time and pasting temperature of starch in noodles,the influence on pasting temperature of starch was not significant.