Effect Of Vitamin C Treatment Assisted By Vacuum Impregnation On The Quality Of Fried Potato Chips

Potato tubers are rich in vitamin C(Vc),which is 10 to 30 times that of apples,grapes and pears.Potatoes can be made into fried fries,potato chips and other products.However,during frying,the loss of V_Cwill increase due to the high temperature.Therefore,it is one of the urgent problems to be solved in potato processing industry to choose appropriate methods to reduce the loss of heat-sensitive nutrients.In this study,potatoes(produced in Wuchuan,Inner Mongolia)were selected as raw materials to investigate the strengthening effect of vacuum impregnation(VI)auxiliary treatment on the Vc of fried potato chips.Firstly,this study uses VI assisted Vc solution to process fresh-cut potatoes.At the same time,this study used Vc content as an indicator to investigate the effects of vacuum time,immersion time,and Vc solution concentration on the Vc content of fresh-cut potatoes,and then screened out the best VI treatment conditions.Secondly,this study investigated the effects of different processing conditions on the Vc content,value of chromatism(ΔE)and crushing force of fried potato chips.Finally,this study investigated the changes in value of chromatism,oil content,acid value,water content,crushing force,Vc content,polyphenol content and antioxidant capacity of fried potato chips during storage.In this study,VI assisted Vc treatment was used to reduce Vc loss during the processing of fried potato chips.The main findings are as follows:(1)The optimal VI assisted V_Cprocessing conditions were as follows:vacuum time of 8min,impregnation time of 5 min,V_Csolution concentration of 15 g/L.In this study,Vc content of fresh-cut potatoes treated with Vc assisted by VI was significantly higher than that of untreated potatoes(P<0.05),which proved that VI as an auxiliary means can significantly increase the content of Vc in potatoes.(2)The effects of different processing conditions on the Vc content and color of fried potato chips were studied.The results showed that the optimum processing conditions were shown as follows:blanching temperature 80℃,blanching time 10 min,drying temperature50℃,drying time 10 min,frying temperature 170℃,frying time 105 s;when the value of chromatism is the main processing conditions:blanching temperature 85℃,15 min for blanching time,drying temperature 60℃,drying time to 20 min,frying temperature 180℃,120 s.On this basis,the optimum process conditions were determined by experiments,which were blanching temperature 80℃,blanching time 10 min,frying temperature 170℃,frying time 105 s.(3)During the storage period,with the extension of time,theΔE,acid value,water content and crushing force of fried potato chips showed an increasing trend,while the Vc content,polyphenol content and antioxidant capacity decreased.During the same storage period,Vc content,phenol content and antioxidant capacity of fried potato chips treated with VI were higher than those of the control group(Un-VI group),while the other indexes were lower than those of the control group(Un-VI group).Under the storage condition of 4°C,the water content,V_Ccontent,polyphenol content and antioxidation ability of the samples treated with VI were higher than those stored at 20°C.In conclusion,VI treatment after low temperature storage can not only improve the V_Ccontent of fried potato chips,but also delay the quality deterioration of fried potato chips during storage.