Nutritional Quality Evaluation And Study Of The Functional Compositions And Antioxidant Activities In Quinoa From Qinghai

In this study,different quinoa resources of Qinghai were used as materials to systematically evaluate the nutritional and functional qualities;the content of nutrition and function and antioxidant activity in different quinoas were clarified,the content of nutrition and function and antioxidant activity in different regions were clarified.The paper can provide theoretical basis and scientific guidance for selection of quinoa varieties,special resources for processing,and selection of cultivation areas.The main results were as follows:In terms of crude protein,the content of yellow quinoa was the highest,and the content of red quinoa was the lowest.In starch,the total starch content of white quinoa was the highest,the total starch content of yellow quinoa was the lowest,but the content of amylose was the highest.The variation of amylose content in three kinds of quinoas was larger.In terms of fat,the content of red quinoa was the highest,and the content of white quinoa was the lowest.White quinoa had the highest fiber content and the red quinoa had the highest ash content.119 quinoas were divided into three classes using clustering analysis,in the class?,fiber and ash content were highest,amylose/amylopectin ratio and protein content were lowest;in the class?,ash content were lowest;in the class?,amylose/amylopectin ratio,proteinand fat content were highest.The optimum processing conditions of extracting saponins from quinoa using ultrasonic assisted technology was:alcohol concentration 90%,liquid-solid ratio 1:15,extraction power 400 W,extraction temperature 45?,extraction time 25minutes,under this condition,saponins content was 115.74 mg/100g;The optimum processing conditions of free phenols from quinoa using ultrasonic assisted technology was:70%acetone,liquid-solid ratio 1:20,hydrochloric acid concentration0.5%,extraction temperature 35?,extraction power 450 W,extraction time 25minutes,under this condition,free phenols content was 863.62 mg/100g;the optimum processing conditions of bound phenols from quinoa using alkaline method was:using NaOH as extraction reagent,liquid-solid ratio 1:25,extraction time 85minutes,extraction temperature 100?,alkaline concentration 4 moL·L^-1,under this condition,bound phenols content was 286.3 mg/100g.The average free phenols and flavonoids contents of 119 quinoas resources in Qinghai were higher than those of bound phenols and flavonoids.The scavenging abilities of DPPH·and ABTS⁺·of bound phenols were higher than those of free phenols,but the FRAP of free phenols was higher than bound.The content of functional components and antioxidant activities of three kinds of quinoas were significantly different?p<0.05?;the average content of bound phenols in white was the highest,and the average content of saponins and free phenols were the lowest;saponin and free phenols in red were the highest,and the average content of bound phenols was the lowest;the average content of saponins,free phenols,and bound phenols of the yellow were all medium.In terms of DPPH·scavenging capacity,the activities of saponins in red quinoas and the activities of phenols in red quinoas were the strongest;in the case of FRAP,the activities of saponins and phenols of red were the strongest;ABTS⁺·scavenging ability,the saponins and free phenols activities of red and bound phenols of white were the strongest.There were significant differences in the contents of nutritional,functional components and antioxidant activities among quinoas?p<0.05?.In terms of nutrients,the average content of crude fiber,fat,total starch,and crude protein from Xining was higher than that in Wulan;the average content of amylose in Wulan was higher than that in Xining,but there were significant differences among different resources.In terms of functional ingredients,the average content of free phenols in quinoas from Xining was higher than that in Wulan.The average content of free flavonoids,bound flavonoids,bound phenols and saponins inWulan were higher than that in Xining.In terms of antioxidant activity,ABTS⁺·scavenging capacity of free phenols in Xining was higher than that of Wulan,The DPPH·scavenging capacity of free phenols and DPPH·scavenging capacity,ABTS⁺·scavenging capacity,FRAP of bound phenols,DPPH·scavenging capacity,ABTS⁺·scavenging capacity,and FRAP of saponins in Wulan quinoas were all higher than that of Xining.