Effect Of Ball Milling Technology On The Quality Of Foxtail Millet Flour And Noodles

Foxtail millet has both nutritive and medicinal value,but its development is limited due to the lack of gluten protein,the problems of easy breaking and rough surface when it is processed into noodles.Through ball milling modification of foxtail millet flour under different conditions,this thesis explores the changing laws of the modified foxtail millet flour in physical and chemical properties,dough processing characteristics,foxtail millet noodles processing quality and changes in characteristics of blood glucose regulation in vitro,which provides a theoretical basis for the industrialization of millet noodles.The main conclusions are as follows:(1)After foxtail millet flour was milled for different milling time(0.5 h,1 h,2 h,4h,6 h,8 h),milling speed(250 r/min,350 r/min,450 r/min,550 r/min),and ball to powder ratio(1:1,2:1,3:1,4:1),it was found that the structure and physical and chemical properties of foxtail millet flour changed significantly: the ordered structure of starch granules was destroyed,and the crystallinity decreased,leading to the gradual decrease of the particle size,which led to the increase of damaged starch content and the decrease of amylose content;The hydration capacity of foxtail millet flour was improved,and the swelling power of millet flour was increased about 5 times by ball milling time treatment,which was about 2 times higher than ball milling speed and ball to material ratio treatment,contributing to the improvement of dough viscoelasticity;The peak viscosity and final viscosity of the gelatinization parameters were also improved about 2 times under ball milling time.(2)By studying the rheological properties and thermo mechanical properties of foxtail millet dough made from foxtail millet flour under different ball milling modification conditions,it was found that compared with the blank group,the values of G’and G’ of the dough increased with the increase of ball milling degree,and the viscoelasticity was better at 4 h,450 r/min and 3:1 respectively,and the improvement effect of the dough was better than that of the ball milling speed and ball material.The results of dough thermo mechanical properties showed that gluten strength could be improved under the treatment of ball milling speed and ball material ratio,which was in line with the standard for making noodles.When the ball milling time was 4 h,the six indexes of water absorption,mixing index,gluten index,viscosity,amylase and retrogradation index all fell within the target area of noodles,which was in line with the conditions for making better quality noodles.(3)The texture,cooking and sensory properties of foxtail millet noodles made from millet flour modified by different ball milling conditions were studied.It was found that the tensile strength of 30% millet noodles increased significantly compared with that of the non ball milling group.The elasticity and stickiness increased with the prolongation of ball milling time,but decreased with the increase of ball milling speed and ball material ratio;The breaking rate,cooking loss rate and water absorption rate of noodles were significantly reduced,and the improvement effect of ball milling time conditions on noodles was better than that of ball milling speed and ball material ratio conditions,and the best score was reached at 4 h of ball milling.(4)The ability of foxtail millet noodles to regulate blood glucose in vitro was evaluated,and it was found that the ball milling treatment technology had significantly improved its hypoglycemic activity of α amylase inhibition,glucose adsorption,glucose diffusion and dialysis delay index were more obvious when the ball milling time was 4h and 6 h,the ball milling speed was 350 r/min and 450 r/min,and the ball to material ratio was 4:1,which were about 1.5 times as much as the blank group.The results of the basic quality of noodles showed that the modified millet flour prepared under the conditions of ball milling time 4 h,ball milling speed 350 r/min,and ball material ratio 2:1 was more suitable for making noodles with better taste;According to the comprehensive analysis of the ability of regulating the blood sugar of noodles in vitro,it was found that under the conditions of 4 h ball milling time,450r/min ball milling speed,and 3:1 ball material ratio,the requirements for making healthy noodles were better.