Effects Of Peeling Degree And Milling Methods On The Quality Of Wheat Flour And Noodles

The nutrients of wheat flour produced by traditional wheat finishing technology are seriously lost,and the whole wheat products are difficult to be accepted by consumers because they contain all bran,germ and other components.Therefore,the technology of peeling before milling can not only effectively retain the nutrients in bran,but also improve the taste of the final products,which is conducive to the development of flour food with both nutrition and taste.In this paper,Jinan 44 wheat was used as the raw material,and the peeling process was combined with the two milling processes of whole wheat flour to prepare five kinds of entire grinding flour and bran recombining flour with different peeling degree,and explored the effects of peeling degree and milling methods on nutritional quality and processing quality of wheat flour.And further processed wheat flour made into noodles,to explore the effects of peeling degree and milling methods on the taste quality of noodles,provide a theoretical basis for the production of different quality requirements of wheat flour.The main findings are as follows:(1)Effects of peeling degree and milling methods on nutritional quality of wheat flour.Peeling had a significant effect on the content of basic components and bioactive substances in wheat flour.At the maximum peeling degree,the protein content of EGF and BRF decreased by 8.60%and 5.21%respectively,the ferulic acid content decreased by 39.33%and 28.12%respectively,the erucic acid content decreased by 6.13%and 5.43%,the total antioxidant activity decreased by 7.98%and 7.89%and the starch content increased by 1.96%and 1.68%.At the same time,the content of phytic acid and total flavonoids showed a trend of first increasing and then decreasing with the increase of the peeling degree,and the maximum value appeared at about 3%of the peeling degree.Compared with the two milling methods,the protein,ferulic acid and erucic acid content of BRF were higher than that of EGF under the same peeling degree.The contents of starch,phytic acid and total flavonoids of EGF were higher than those in BRF.The total antioxidant capacity of EGF was higher than that of BRF except the peeling degree of 11%.(2)Effects of peeling degree and milling methods on the processing quality of wheat flour.With the increase of peeling degree,the chroma L~*values of EGF and BRF increased,while a~*and b~*values decreased.The gelatinization indexes increased,but the thermodynamic indexes decreased.Peeling had little effect on gluten content and blending parameters of wheat flour.With the increase of peeling degree,the values of elastic modulus(G’)and viscous modulus(G’’)in dynamic rheological properties of wheat dough decreased,while the apparent viscosity and the creep recovery ability increased.Moreover,with the increase of peeling degree,the micro structure of wheat dough became more uniform and dense,and the number of free starch granules and irregular voids decreased significantly.The results showed that the L~*value of EGF was higher than that of BRF,while a~*value and b~*value were lower than that of BRF under the same degree of peeling.The gelatinization properties,thermodynamic properties and creep recovery ability of EGF were lower than those of BRF.And the flour milling method had little effect on gluten content and mixing characteristics.At the same time,the dynamic rheological properties G’and G’’value and apparent viscosity of EGF were higher than those of BRF.The microstructure of BRF dough was more stable than that of EGF dough.(3)Effects of peeling degree and milling methods on eating quality of noodles.The L~*value of EGF and BRF noodles increased and the a~*value decreased with the increase of peeling degree.The optimal cooking time,water absorption rate and cooking loss rate of noodles decreased,while the sensory score increased with the increase of peeling degree.Under the same peeling degree,there was no significant difference in L~*and a~* values between the two milling methods.The noodle made of BRF had higher water absorption and cooking loss,and lower sensory score than that of EGF.