Effect Of Soluble Soybean Polysaccharides On The Quality Of Youtiao And Synergistic Anti-aging Effect With Storage Temperature

As a traditional fried food,youtiao is very appreciated by the consumers.Nowadays,with people's increasing concern about healthy diet,the consumption of youtiao is affected by its high oil content and poor taste after storage.Soluble soybean polysaccharides(SSPS)are natural polyanion polysaccharides isolated from the soybean meal that is removed from oil and protein,and have a structure similar to pectin.In this study,SSPS were added to youtiao for reducing the oil content,retarding the staling rate,and improving the consumption quality.Firstly,the effect of SSPS on the processing characteristics of flour and dough was studied.Furthermore,the effect of SSPS on the quality characteristics of youtaio was explored.Finally,the effect of SSPS and freezing storage on the staling of youtiao and its mechanism were discussed.The main conclusions were as follows:(1)The effect of SSPS on quality-improving of wheat flour and dough were studied.The results showed that farinograph quality number was increased while degree of water absorption and softening were decreased when adding SSPS in wheat flour.SSPS significantly improved the farinograph quality of wheat flour.In addition,SSPS lowered the peak viscosity,breakdown value and setback value during pasting,protected the integrity of the starch granules,and inhibited the short-term retrogradation of the starch.The addition of SSPS maintained the relative stability of the flour paste system under shear force.Hydrogen bonding and electrostatic interaction may be the main forces for stabilizing the SSPS-starch blend system.Addition of SSPS could improve the extensogragh of dough,resulting in an increase in development time,stability time,ernergy,resistance,ratio of extensibility and the elastic modulus but a decrease in the extensibility.SSPS had a good effect on improving the gluten structure.SSPS increased the content of sulfhydryl groups in the dough,leading to prevent protein from aggregation.(2)The effect of SSPS on quality-improving of youtiao was studied.The results showed that specific volume,porosity and yellowness value of youtiao increased,while the hardness and oil content of youtiao decreased with the increase of SSPS addition(0.3-1.0%).When SSPS addition amount was 1.0%,the specific volume of youtiao reached the highest value of 3.88 cm3/g,and the hardness,chewiness and oil content reached the lowest values of 7894.56 g,4006.64 g and 8.14%,respectively.(3)The effect of SSPS on bacteriostatic and anti-staling of youtiao was studied.The results showed that storage at-18? greatly inhibited the deterioration of youtiao quality in terms of the water migration rate,aging enthalpy and crystallinity,which were significantly lower than those stored at 4? and room temperature.The swelling power,solubility and soluble amylose content were weakened at-18?.With the addition of SSPS,the water migration rate,aging enthalpy and crystallinity of youtiao were further reduced,and the swelling power,solubility and soluble amylose content were decreased.SSPS and frozen storage could protect youtiao from staling by inhibiting moisture migration and starch recrystallization.