微波真空干制加工对荷叶茶酚类物质含量及其抗氧化活性的影响  

Effect of Microwave Vacuum Drying on Contents of Phenolic and Antioxidant Activity of Lotus Leaf Tea

作　　者：刘慧娟[1] 郑云展 陈燕霞[1] 石从桢 苏东晓[1,2] 

机构地区：[1]长江大学生命科学学院,湖北荆州434025 [2]长江大学荆楚特色食品研发中心,湖北荆州434025

出　　处：《食品科学技术学报》2016年第3期40-45,共6页Journal of Food Science and Technology

基　　金：长江大学青年科研支持计划基金项目(2015CQN62);长江大学荆楚特色食品研发中心开放基金项目(2015JSF01)

摘　　要：干制脱水加工被广泛应用于农副产品的保藏和精深加工,但是干制加工会影响产品活性物质的含量,导致其生物活性发生改变。为了研究微波真空干制功率对荷叶酚类物质的影响,比较了300,400,500 W等不同微波功率真空干制及热风干燥、日晒条件下,荷叶酚类物质含量变化;采用DPPH和FRAP方法比较不同微波功率产品的抗氧化活性差异。结果表明,荷叶经微波真空干制加工后,总酚和总黄酮含量较热风干燥法显著提高,分别是后者的1.79和1.76倍;荷叶提取物抗氧化活性显著提高,微波真空干制荷叶清除DPPH·活性优于热风干燥方式,300,400,500 W微波功率干制荷叶清除DPPH·IC50值分别是62.52,49.31,43.59μg/m L;微波功率500 W干制荷叶提取物FRAP抗氧化活性分别是日晒荷叶和热风干燥荷叶的3.18和1.82倍。抗氧化活性指标与酚类物质含量相关性分析发现,荷叶总黄酮含量与FRAP和DPPH为极显著相关,表明微波真空干制能够显著影响荷叶酚类物质含量,进而增强其抗氧化活性。Drying is commonly used for preservation and deep processing of agricultural byproducts.However,the contents of active substances may be altered during the drying process,resulting in decrease of biological activities. In order to study the effect of power of microwave vacuum drying on phenolic substances in lotus leaf tea,effects of microwave drying under different power（ 300,400,and 500W）,hot air drying,and sun drying on the contents of phenolic compounds and its antioxidant activity in lotus leaf tea were investigated. DPPH radical scavenging capacity and ferric reducing antioxidant power（ FRAP） were used to analyze the antioxidant activities. The results showed that the contents of total phenolcis and total flavonoids in lotus leaf tea treated by microwave vacuum drying were 1. 79 and 1. 76 folds higher than those of traditional hot air drying products. Microwave vacuum drying lotus leaf exhibited higher antioxidant activity in DPPH· scavenging activity（ IC50 values 62. 52,49. 31,43. 59 μg / m L,respectively） comparing to hot air drying products. In addition,the FRAP value of microwave vacuum drying（ 500 W） samples was 3. 18 and 1. 82 folds higher than that of sun drying and hot air drying smaples. The Pearson correlation analysis between antioxidant activity and phenolic compounds showed that the content of total flavonoids in lotus leaf was significantly correlated with DPPH and FRAP,indicating that the microwave vacuum drying would significantly affect the content of phenolic compounds in lotus leaf,and then enhance its antioxidant activity.

关 键 词：荷叶 真空微波 酚 抗氧化 自由基 

分 类 号：TS255.1[轻工技术与工程—农产品加工及贮藏工程] TS272.5[轻工技术与工程—食品科学与工程]