Effect Of Pre-gelatinization On The Quality Of Whole Oat Flour And The Quality Of High Content Oat Noodles

Oat,a kind of cereal with balanced nutrition and cholesterol-lowing function,is favored by consumers.However,the oat flour contains little gluten,and its dough is difficult to be shaped,limiting its application as staple food.Therefore,in this paper,oat flour was pre-gelatinized by steaming,extruding and drum drying.Based on the analysis of the physical and chemical properties of pre-gelatinized oat flour,the effects of pre-gelatinized oat flour on the properties of oat-wheat mixed flour,dough properties and quality of high addition amount(70%)oat noodles were studied.The main research contents and results were summarized as follows:(1)The raw whole oat flour(ROF)was raw material.It was pre-gelatinized by steaming,extruding and drum drying,and then obtained fried oat flour(FOF),extruded oat flour(EOF)and drum drying oat flour(DOF).The effects of different pre-gelatinization methods on their physical and chemical properties were compared and analyzed.The results showed that,after pre-gelatinization,the peroxidase and lipase were inactivated,the gelatinization degree of oat flour increased significantly(p<0.05).Water absorption index,water solubility index and swelling power increased.The viscosity at room temperature increased.The pasting properties changed significantly.Therefore,pre-gelatinization can effectively improve the processing adaptability and storage stability of oat flour.(2)ROF,FOF,EOF and DOF were used as raw materials.FOF and wheat flour were mixed at 7: 3,and then ROF was replaced by different proportion of FOF,EOF and DOF.The effects of different types and amounts of pre-gelatinized flour on properties of mixed flour and noodles quality were studied.The results showed that,with the proportion of pre-gelatinized flour in mix-dough increasing,the viscosity at room temperature of mixed flour increased.In the range of 0%~70%,the viscosity of mixed flour was positively correlated with the amount of FOF,and negatively correlated with the addition of EOF and DOF,and peak time decreased with the addition amount increasing.Different pre-gelatinized flour can improve the noodles quality,and adding 70% FOF,mechanical properties and cooking quality of noodles were the best,and the sensory scores were the highest.The hardness,adhesiveness,chewiness of oat noodles correlated with RVA parameters of mixed flour.Therefore,the quality of oat noodles can be estimated according to the RVA parameters of the mixed flour.Replacing all the ROF in the mixed flour with FOF contributed to the best noodles quality.(3)FOF,EOF and DOF were used as raw materials.FOF and wheat flour were mixed at 7:3,and then FOF were replaced by different proportion of EOF and DOF.The effects of different substitution of EOF,DOF and different dough moisture content on dough properties were studied.The results showed that,the pasting properties of mixed flour changed significantly.Peak viscosity,trough viscosity,final viscosity and setback decreased,and pasting temperature increased.When the formula was same,increasing the dough moisture content conduced to reduce its hardness and enhance ductility,but increased the adhesion and reduce the elasticity.The optimal moisture content of different mixed dough of 70% FOF,5% EOF+65% FOF,10% EOF+60% FOF,15% EOF+55% FOF,5% DOF+65% FOF,10% DOF+60% FOF,15% DOF+55% FOF(the remaining 30% were wheat flour)were were 45%,44%,43%,42%,44%,43%,43%.At the optimum moisture content,the maximum adhesion force,adhesiveness,adhesion distance and resistance to extension of dough increased with EOF or DOF addition increasing.The dough resistance to extension containing DOF were larger than that of EOF at the same addition.Therefore,the moisture content of dough affected its texture properties and extension properties.5%~15% EOF or DOF instead of FOF could enhance the dough internal binding force,and the effect of DOF was better than that of EOF.(4)FOF,EOF and DOF were used as raw materials.FOF and wheat flour were mixed at 7:3,and then FOF were replaced by different proportion of EOF and DOF.The effects of different substitution of EOF,DOF on 70% oat noodles quality were studied.The results showed that,with the addition of EOF and DOF increasing,the elastic modulus and fracture stress of dry noodles increased.The cohesion,elasticity and chewiness of the noodles after cooking increased,but the adhesion and cooking loss increased.The elastic modulus and fracture stress are larger,cooking loss was smaller of noodles containing DOF,if adding the same amount.Therefore,5%~15% EOF or DOF instead of FOF can improve 70% oat noodles quality,and the effect of DOF was better than EOF.