目的 建立防己Stephaniae Tetrandrae Radix趁鮮切制熱風(fēng)干燥的干燥動(dòng)力學(xué)模型，測(cè)定其干燥特性參數(shù)，研究其干燥過程中的成分變化規(guī)律，為闡明防己趁鮮切制熱風(fēng)干燥機(jī)制及干燥工藝提供參考依據(jù)。方法 在60、70、80 ℃條件下建立防己趁鮮切制干燥過程中的干燥動(dòng)力學(xué)模型，基于低場(chǎng)核磁共振技術(shù)研究防己干燥過程中的水分相態(tài)，根據(jù)Fick擴(kuò)散定律和Arrhenius方程計(jì)算出有效擴(kuò)散系數(shù)（effective diffusion coefficient，D_eff）和活化能（activation energy，E_a），采用HPLC法對(duì)防己干燥過程中指標(biāo)成分粉防己堿和防己諾林堿的質(zhì)量分?jǐn)?shù)進(jìn)行動(dòng)態(tài)監(jiān)測(cè)。結(jié)果 Page模型（MR＝e^−ktn，MR為水分比，k，n為模型參數(shù)）可以準(zhǔn)確地描述防己干燥過程中水分含量的變化，溫度越高，水分散失越快，模型中的參數(shù)k隨著溫度的升高而增大，參數(shù)n隨著溫度的升高而減??；60、70、80℃熱風(fēng)干燥條件下的D_eff分別為8.13×10⁻⁷、9.97×10⁻⁷、1.04×10⁻⁶ m²/s，D_eff隨著溫度的升高而增大；防己趁鮮切制熱風(fēng)干燥的E_a為12.51 kJ/mol。橫向弛豫時(shí)間（T₂）圖譜顯示，4 h之前水分相態(tài)發(fā)生顯著變化，自由水比例大幅下降，水的自由度逐漸降低；4 h之后水分含量和相態(tài)無明顯變化。防己在趁鮮切制干燥過程中，粉防己堿和防己諾林堿總含量無明顯波動(dòng)。結(jié)論 采用干燥動(dòng)力學(xué)模型和低場(chǎng)核磁共振技術(shù)可以直觀地描述防己趁鮮切制干燥過程中的水分變化規(guī)律；為闡明防己趁鮮切制干燥機(jī)制和干燥工藝提供參考。

Objective To establish the drying kinetic model of Fangji (Stephaniae Tetrandrae Radix, STR) fresh-cut hot air drying, determine its drying characteristic parameters, and study the variation of its components during the drying process, so as to provide a reference for elucidating the drying mechanism of STR fresh-cut and optimizing the drying process. Methods The drying kinetics model of STR during fresh-cut drying was established at 60, 70, 80 ℃. The water phase in the drying process of STR was studied based on low-field nuclear magnetic resonance technology. The effective diffusion coefficient (D_eff) and activation energy (E_a) were calculated according to Fick’s diffusion law and Arrhenius equation. The mass fraction of tetrandrine and fangchinoline in the drying process of STR was investigated by HPLC for dynamic monitoring. Results The Page model (MR = e^−ktn, MR is water ratio, k, n are model parameters) could accurately describe the change of moisture content in the drying process of STR. The higher the temperature, the faster the moisture loss. The k in the model increased with the increase of temperature, and the n decreased with the increase of temperature. D_eff were 8.13×10⁻⁷, 9.97×10⁻⁷, 1.04×10⁻⁶ m²/s at 60, 70, 80 ℃, and the effective diffusion coefficient increases with the increase of temperature. The E_a value was 12.51 kJ/mol. The T₂ spectrum showed that the water phase changed significantly before 4 h, the proportion of free water decreased significantly, and the degree of freedom of water decreased gradually. There was no significant change in water content and phase state after 4 h. In the process of fresh-cut drying, the total content of tetrandrine and fangchinoline had no obvious fluctuation. Conclusion The drying kinetics model and low field nuclear magnetic resonance technology can intuitively describe the moisture change law of STR during fresh-cut drying process. It provides a reference for elucidating the drying mechanism and drying process optimization of STR fresh-cut.

R283.6

國(guó)家自然科學(xué)基金項(xiàng)目（82060724）;國(guó)家自然科學(xué)基金項(xiàng)目（82460772）;省重點(diǎn)研發(fā)計(jì)劃項(xiàng)目（20243BBI91015）;江西省中醫(yī)藥標(biāo)準(zhǔn)化項(xiàng)目（2023A19）;江西省高水平本科教學(xué)團(tuán)隊(duì)（2252201013）;校級(jí)虛擬教研室（2252300109）