Genetic Diversity In Nutritional And Physicochemical Properties Of Potato Wholemeal Flour

Potato is the fourth most important food crop in the world.Because of its high nutritional value and low planting and storage costs,it has broad development prospects.The potato wholemeal flour is rich in starch,protein,minerals and various antioxidants,which can fully meet the nutritional requirements of the human body.In this study,the genetic diversity in the phenolics,protein,amino acids,minerals and physicochemical properties of 14 potato accessions was investigated,and their pair-wise correlations were analyzed.The main results are as follows:1.The phenolics of potato flour are mainly divided into two types: free phenolic and bound phenolic,among which free phenolics accounts for 60.6-99.5% of total phenolic content(TPC).Among the free phenolics,chlorogenic acid,neochlorogenic acid,cryptochlorogenic acid,and p-coumaric acid were detected in most accessions.Among the bound phenolics,caffeic acid,ferulic acid and p-coumaric acid were detected in the colored potatoes.Correlation analysis indicated that the chlorogenic acid and ferulic acid were significantly positively correlated with TPC and antioxidant activity,while the p-coumaric acid,cryptochlorogenic acid and neochlorogenic acid were not correlated with TPC and antioxidant activity.Pelargonidin-3-p-coumaorylrutinoside-5-glucoside was identified in the red flesh potatoes.Petunidin-2-p-coumarylrutinoside-5-glucoside and pelargonidin-3-feruloylrutinoside-5-glucoside were identified in the purple flesh potatoes.2.The average protein content of potato was 9.81 g /100 g DW(dry weight basis)and the range was 7.89-11.81 g /100 g DW.The total amino acid content of 14 potato accessions was 75.70 mg/g DW.The two most abundant amino acids were Asp and Glu,which are significantly positively correlated with most other amino acids.In terms of mineral elements,the average contents of 12 mineral elements were in the order of K > P > Mg > Ca > Zn > Fe > Mn > Cu > Ni > Cd > Se > Cr.K and P contents were the highest among all accessions,which were positively correlated with most of the other minerals.3.The average starch content of potato wholemeal flour was 64.09g/100 g DW,and the range was 49.33-72.09%.In terms of pasting and textural properties,the range of the peak viscosity(PV),hot paste viscosity(HPV)and cold paste viscosity(CPV)was in the range of 268.21-398.84 rapid visco unit(RVU),158-250.63 RVU,and259.88-418.79 RVU,respectively.The hardness values(HD)and cohesiveness(COH)of different potato wholemeal flour are very different.The variation range of HD ranged from 5.75 to12.79 g,and COH ranged from 0.22 to 0.83.The gelatinization onset(To),peak(Tp),conclusion(Tc)temperatures and enthalpy((35)Hg)were in the ranges of 64.77-69.35?,69.72-74.99?,75.37-82.01?,7.46-11.07J/g,respectively.The gelatinization temperature was negatively correlated with the enthalpy of gelatinization and the enthalpy of retrogradation.There is a significant positive correlation between the enthalpy of gelatinization and the enthalpy of retrogradation.