Study On The Effect Of Yogurt And Quinoa On The Quality Of Dough And Naan

Yogurt and quinoa are rich in protein,amino acids,minerals,and physiological active substances,with antioxidant properties;Yogurt is also rich in probiotics,promoting human health.Naan is a kind of flour product that is necessary for people all over Xinjiang,with palatable taste,nutritious and healthy characteristics.People are gradually pursuing a balanced diet,and the research and development of highly nutritious and multi dietary naan has become a focus.Yogurt and quinoa are rich in protein,physiological active substances,and can be used as antioxidants.In this experiment,yogurt and quinoa flour were added to wheat flour to study the effects of yogurt and quinoa flour on the physicochemical properties of dough,respectively;Chemical changes in yogurt and quinoa mixed dough during fermentation;Changes in the quality of naan during storage after optimization of its processing;The starch digestion characteristics of naan and its antioxidant activity changes after digestion.The results are as follows:(1)With the addition of yogurt,the proportion of weakly bound water to free water decreases,while the bound water increases;For the gelatinization characteristics of dough,adding yogurt appropriately can improve the thermal stability of dough;The content of disulfide bonds and sulfhydryl groups in yogurt dough is inversely proportional;The content of flavonoids,polyphenols,free radical scavenging rate,and iron reductive force in dough increased;A certain proportion of yogurt increases the extracellular polysaccharide content in dough;The amount of yogurt remains unchanged,and the fermentation time is proportional to the fermentation power of the dough;The fermentation time remained unchanged,and the fermentation power of yogurt dough increased first and then decreased,both higher than that of the blank group.(2)Adding quinoa flour can reduce the whiteness of the dough;The combined water decreases and the water holding capacity decreases;When dough is gelatinized,quinoa flour can delay the aging of dough to a certain extent;The content of disulfide bonds and sulfhydryl groups in quinoa dough varies in direct proportion;Increased flavonoid and polyphenol content,free radical scavenging rate,and iron reductive power;At the same time,the fermentation power of quinoa dough gradually decreased,both lower than the blank group.(3)During the entire fermentation period,the p H value of wheat dough,yogurt dough,quinoa dough,and yogurt quinoa dough decreased,while the TTA value increased.For water activity,wheat dough and yogurt dough first increased and then decreased;Quinoa dough and yogurt quinoa dough are inversely proportional to fermentation time.The reducing sugar content of yogurt dough,quinoa dough,and yogurt quinoa dough increased first and then decreased,all higher than that of wheat dough.The content of water soluble substances,polyphenols,and flavonoids in dough increased to varying degrees,among them,yogurt and quinoa mixed dough are the highest.The X-ray diffraction results indicate that the dough has an A-type crystalline structure,and the addition of yogurt and quinoa does not alter the crystal structure of starch.Wheat dough had the largest β-fold and the smallest α-helix.Therefore,the addition of yogurt and quinoa changed the original protein network structure.In terms of microstructure,yogurt compacts the structure of the dough;The structure of quinoa dough is loose and discontinuous,and the pores become larger;Yogurt and quinoa mixed dough have a denser structure.The fermentation time remains unchanged,and the G’> G’’ of all dough indicates that the dough belongs to a viscoelastic solid;The addition of yogurt and quinoa changes the elasticity of the dough.(4)Through a single factor,response surface design,the optimal formula for yogurt naan was obtained as follows: yogurt addition 14.5%,yeast addition 0.9%,fermentation temperature 35℃,fermentation time 92 min,average sensory score 84.5,hardness 3943.38;On this basis,to study the effect of quinoa on the quality of naan and determine the addition amount of quinoa by 10% through correlation analysis,a yogurt quinoa naan was prepared.(5)During normal temperature storage,the water activity of naan decreased at a rate of wheat naan>yogurt naan>yogurt quinoa naan>quinoa naan.The water content of quinoa naan and yogurt quinoa naan varies in direct proportion to time.The gelatinization degree of naan is inversely proportional to time.At the end of storage,the gelatinization degree of quinoa naan is the smallest,indicating that the addition of quinoa flour has a delaying effect on the aging of naan.With the increase of days,the content of polyphenols,flavonoids,DPPH clearance rate,and ABTS clearance rate of naan decreased.During cold storage: the water activity and p H value of naan decreased slowly.The water content fluctuates in a small range.The gelatinization degree and antioxidant capacity decrease with time,but the decline rate is slow.With the increase of storage days,the antioxidant capacity of naan decreased,but the decline rate was slow.This indicates that cold storage can delay the changes in the quality of naan.(6)The binding force of starch and iodine in yogurt quinoa naan,is the lowest,indicating that mixing the two is more effective in preventing the binding of starch molecules to iodine compounds.Overall,with the increase of temperature,the solubility and swelling degree of starch in naan basically showed an increasing trend.Yogurt quinoa naan has the best starch transparency and the lowest sedimentation rate.Yogurt naan,quinoa naan,yogurt quinoa naanα-fluorescence intensity decreases after the interaction of amylases.The starch hydrolysis rate of naan is proportional to the digestion time,and the yogurt quinoa naan has the lowest starch hydrolysis rate.The content of polyphenols in digestive fluid increased sharply at first and then increased steadily.The flavonoid content of all naans fluctuated.During digestion,antioxidant activity increases to varying degrees;The reducing power and the ability of ABTS to scavenge free radicals of yogurt quinoa naan,are higher.