The Effects Of Adding Tartary Buckwheat Flour On Rice Flour Dough Rheological Properties And Bread Quality

About 1% to 2% of the world's population is allergic to gluten.The only available treatment is to adhere gluten-free diet throughout the life.Rice and tartary buckwheat are full of nutrition,which can make up the deficiencies for gluten-free dietary.It can also meet the food safety and nutritional needs for gluten allergy and celiac disease patients.This study chose Yanfeng 47(YF),Liaojing 294(LJ)and Akitakomati(AK)rice flour as raw materials,and mixed with tartary buckwheat flour(TBW)at the ratio of 90:10,80:20 and 70:30 to form rice flour/TBW mixed flour,respectively.The effects of different varieties of rice flour and the addition ratio of TBW flour on dough characteristics and bread quality were investigated.The results were as follows:The TBW flour showed weaker water binding capacity(WBC),but higher water holding capacity(WHC)and water solubility index(WSI)than YF,LJ and AK rice flour.The YF rice flour showed lower WHC,but higher water absorption index(WAI)and swelling power(SP).The LJ rice flour showed weaker WBC,but the WAI and SP were strong.The AK rice flour showed strong WHC and WBC,but the WAI and SP were weaker.The addition of TBW flour on rice flour showed no significant differences in WSI and oil absorbing capacity(OAC).The YF rice flour and LJ rice flour showed higher paste stability.The addition of TBW flour affected the gelatinization stability of LJ rice flour.However,it showed no effect on the retrogradation of YF/TBW mixed flour and LJ/TBW mixed flour.The addition of TBW flour will promote the retrogradation of AK rice flour.In addition,the WAI of the mixed powder reduced and the gelatinization stability increased,which showed the sticky paste was easily to form.However,the degree of retrogradation increased after cooling.The addition of TBW flour could be used for improving the stability of rice flour gel during processing.The addition of TBW flour reduced the WAI,development time and stability time,while improved the dough viscosity of rice flour dough.It showed no effect on the protein weakening of LJ rice flour dough.The starch gelatinization of YF/TBW mixed flour and LJ/TBW mixed flour were affected by the amount of TBW.A certain amount addition of TBW could inhibit the starch retrogradation of LJ rice flour dough and AK rice flour dough.However,the higher addition of TBW promoted starch retrogradation of YF rice flour and LJ rice flour.The addition of TBW could inhibit the shear thinning of LJ rice flour dough and AK rice flour dough,and stabilized the dough structure made by LJ rice flour AK rice flour.However,the amount of TBW addition showed significant effect on shear thinning,hardness and structure on YF rice flour dough.The AK rice flour and AK/TBW mixed flour showed higher storage modulus(G')and loss modulus(G "),while the addition of TBW flour could decrease the G' and G".The rice flour showed stronger WAI and gelation ability.The addition of TBW flour could adjust the WAI of the mixed dough and the viscosity of the YF rice flour dough.It also could improve the adhesion and cohesion of the rice flour dough,changed the dispersion of the protein in rice flour dough,enhanced the resistance and viscosity of LJ rice flour dough and AK rice flour dough.Besides,It stabilized the structure of LJ rice flour dough and AK rice flour dough,weakened the resistance of YF rice flour dough.The pure rice flour bread made by LJ rice flour showed higher specific volume,elasticity and lower hardness.After the addition of TBW flour,the specific volume and elasticity of LJ/TBW mixed flour bread decreased,while the hardness increased.The specific volume and elasticity of YF/TBW mixed flour bread and AK/TBW mixed flour bread increased and the hardness decreased at a certain amount of TBW flour.It indicated that the addition of rice flour and TBW flour showed significant effects on the characteristics of gluten free dough and bread quality.The LJ rice flour was suitable for making pure rice flour gluten-free bread,while the YF rice flour was suitable for blending with TBW flour for bread making,which could improve the specific volume and springiness of bread,reduced the bake loss and adjusted the hardness of bread.