Antioxidant Capacities Of Different Cultivars Of Kiwifruit And Kiwifruit Nfc Juice In Vitro

Qihong,Wanhong,Jinxiang,Jinyan grown in Zhouzhi,Shaanxi,and Hayward,Qinmei,Xuxiang,Huayou grown in Yangling,Shaanxi were investigated.Their physicochemical properties,antioxidant compounds contents and in vitro antioxidant capacities in fresh fruit,different organization tissues and contents changes in refrigeration were measured.High performance liquid chromatography(HPLC)and fourier transform infrared spectrum(FT-IR)were used to structure the fingerprinting of 8 kiwifruit cultivars.During the fingerprinting,principle component analysis(PCA)and cluster analysis(CA)were used.Sensory evaluation of NFC juice made from different kiwifruit cultivars was investigated.Influences during processes and shelf life on antioxidant compounds contents and antioxidant capacities in vitro were measured.The main research results were as follows:(1)Different kiwifruit cultivars had significant differences in physicochemical properties investigation.The sugar-acid ratios of Qihong,Huayou and Jinyan were over 10,so they were suited for edible use.Different kiwifruit cultivars had significant differences in antioxidant compounds contents and antioxidant capacities in vitro.Huayou had the highest VC,total phenolic acids and flavonoids contents among the 8 cultivars,so it had the strongest antioxidant capacity in vitro.(2)Catechinic acid,epicatechin,protocatechiuic acid and chlorogenic acid were the uppermost phenolic acids in 8 kiwifruit cultivars,which occupied 90.86%~98.07% of the whole phenolic acids been tested.Other phenolic acids been tested in 8 cultivars were gallic acid,caffeic acid,p-coumaric acid,furulic acid,ellagic acid,phloridzin,rutin and quercetin.(3)Storage shelf-lives of 8 kiwifruit cultivars at(1±1)? were sorted from longest to shortest as follows: Hayward,Jinxiang,Qihong,Qinmei,Xuxiang,Huayou,Wanhong,Jinyan.During refrigeration period,changes similar to those during after-ripening on kiwifruit occurred,which manifested that firmness and total acids contents declined,meanwhile SSC rose.During refrigeration period,antioxidant compounds contents in kiwifruit showed not significant changes.(4)Mass of different organization tissues of 8 kiwifruit cultivars had significantdifferences.Total phenolic acids,flavonoids and pigments in peel occupied the most in total fresh fruit,nevertheless which in pulp and core occupied pimping parts.(5)Cuncumers' acceptance of NFC juice made from 8 cultivars had a significant difference.The acceptance order was as follows: Hayward,Jinyan,Jinxiang,Wanhong,Huayou,Xuxiang,Qinmei,Qihong.SSC,VC,total phenolic acids,flavonoids and pigments in NFC juice showed a significant advantage compared to concentrated juice.During the producing processes,VC contents had a slightly rise.However total phenolic acids and flavonoids had a slightly decline.Pigments had a significant decline.For Xuxiang,most influenced cultivar,total chlorophyll and carotenoid seperately had a decline peicentage of80.11% and 53.45%.During the shelf-life,NFC juice could maintained the original antioxidant capacities in vitro.(6)Fingerprinting based on HPLC and FT-IR was effective to distinguish different cultivars.The variance corresponding to the first two principle components based on FT-IR are accounting 84.96%.Absorption bands at 821,869,1115,1249,1410,1627 cm-1 were similar in all kiwifruit cultivars,which were similar to phenolic acids.Classification result based on FT-IR was similar to the result based on HPLC.