真空干燥与冷冻干燥对无花果酚类成分及抗氧化活性的影响

Effects of Vacuum Drying and Freeze Drying on Polyphenol Composition and Antioxidant Activities of Figs(Ficus Carica Linn.)

无花果是一种药食两用的水果,具有重要的经济价值。实验对比分析了真空干燥和冷冻干燥对无花果酚类成分及其抗氧化活性的影响。利用福林酚法测定总酚含量,DPPH和ABTS法检测多酚抗氧化活性,同时采用液质联用技术(UPLC-QqQ-MS/MS)对无花果干燥前后含有的多酚成分进行准确的定性定量分析。结果表明,2种干燥方式对无花果酚类成分及抗氧化活性影响有显著差异,真空干燥和冷冻干燥后无花果总酚含量、DPPH自由基及ABTS自由基清除能力分别是388.65 mg GAE/100 g d.b.、162.25 mg Vc/100 g d.b.、333.08 mg Vc/100 g d.b.和285.71 mg GAE/100 g d.b.、144.44 mg Vc/100 g d.b.、337.76 mg Vc/100 g d.b.。液质分析发现无花果中的主要酚酸是没食子酸和绿原酸,主要类黄酮是芦丁。2种干燥处理均破坏无花果中的多酚成分及其抗氧化活性。但与冷冻干燥相比,真空干燥能够减少无花果中酚类成分及其抗氧化能力的损失。

Fig is an important economic fruits which has been used as food and drug for research.In this study,the effects of vacuum drying(VD)and freeze drying(FD)on the phenolic profile and antioxidant activity of figs were compared.The total phenolic content was determined by Folin-Ciocalteau method,and the antioxidant activity of polyphenols was determined by DPPH and ABTS method.In addition,UPLC-QqQ-MS/MS was used to identify and quantify the polyphenol component in figs.The results showed that there were significant differences between the two drying methods on the phenolic composition and antioxidant activity of figs.The total phenolic content,DPPH and ABTS free radical scavenging capacity of figs dried by VD and FD were 388.65 mg GAE/100 g d.b.,162.25 mg Vc/100 g d.b.,333.08 mg Vc/100 g d.b.and 285.71 mg GAE/100 g d.b.,144.44 mg Vc/100 g d.b.,337.76 mg Vc/100 g d.b.,respectively.UPLC-QqQ-MS/MS analysis showed that gallic acid and chlorogenic acid were the main phenolic acids,and rutin was the main flavonoid in figs.Both VD and FD treatment decreased the contents of polyphenols and antioxidant activities of fresh figs.However,compared with FD,VD could reduce the loss of polyphenols and their antioxidant activities of figs.