热风干燥温度对老山芹品质的影响

Effect of Hot-air Drying Temperature on the Quality of Heracleum moellendorffii Hance

摘要:

本研究探讨不同热风干燥温度（40、60、80、100 ℃）对老山芹干燥特性（干燥曲线、干燥速率曲线、干燥方程拟合）、成分（总多酚、总黄酮、叶绿素）和性质（抗氧化活性、颜色变化）的影响。结果表明：随干燥温度升高，干燥时间显著缩短(p<0.05)。Page方程能准确的描述老山芹热风干燥过程和干燥规律。60 ℃热风干燥处理，总多酚和总黄酮含量均显著高于其他干燥温度（p<0.05），分别为10.97 mg/g和3.45 mg/g，并具有较强的抗氧化活性。60 ℃干燥条件下老山芹所含的黄酮化合物组成含量和叶绿素a含量更高。因此，热风干燥温度不同，对老山芹干燥特性、总多酚、总黄酮、叶绿素含量、颜色及抗氧化活性影响显著不同（p<0.05）。综合考虑，60 ℃热风干燥老山芹在保证较快干燥速率的同时最大程度地保持成分和性质。

Abstract:

The influences of different hot-air drying temperatures (40, 60, 80, 100 ℃) on the drying characteristics (drying curve, drying rate curve, fitted drying equation), composition (total polyphenols, total flavonoids, chlorophyll), and properties (antioxidant activity, color changes) of Heracleum moellendorffii Hance were investigated in this study. The results showed that drying time was significantly (p < 0.05) reduced with an increase of temperature. The Page equation was found to describe accurately the hot air drying process and drying characteristics. Hot air drying at 60 ℃ led to significantly (p < 0.05) higher contents of total polyphenols and total flavonoids (10.97 and 3.45 mg/g, respectively) and higher antioxidant activities than at other temperatures. The contents of flavonoids and chlorophyll a in Heracleum moellendorffii Hance were also higher when drying was conducted at 60 ℃. Therefore, hot-air drying at different temperatures exerted significantly (p < 0.05) different effects on the drying characteristics, content of total polyphenols, content of total flavonoids, chlorophyll content, color and antioxidant activity of Heracleum moellendorffii Hance. Taken together, hot-air drying at 60 ℃ could ensure a higher drying rate while maximally preserving the composition and properties of Heracleum moellendorffii Hance.