Analysis of Safe Storage Moisture Content of Mume Flos Decoction Pieces Based on Theory of Water Activity and Water Molecular Mobility
10.13422/j.cnki.syfjx.20222446
- VernacularTitle:基于水分活度和水分子流动性理论的梅花饮片安全储藏含水量分析
- Author:
Tongtong HAN
1
;
Xiaoyong RAO
1
;
Fengmei QI
1
;
Yan HE
1
;
Guoping ZHAN
2
;
Xiaojian LUO
1
;
Ruilin CHEN
1
Author Information
1. Jiangxi University of Chinese Medicine，Nanchang 330004，China
2. Shenzhen Qianhai Shekou Free Trade Zone Hospital，Shenzhen 518067，China
- Publication Type:Journal Article
- Keywords:
Mume Flos;
decoction pieces;
moisture content;
water activity（Aw）;
water molecular mobility;
low-field nuclear magnetic resonance（LF-NMR）;
adsorption isotherm
- From:
Chinese Journal of Experimental Traditional Medical Formulae
2023;29(13):151-156
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveThe hygroscopic properties of Mume Flos decoction pieces were studied from the perspectives of macroscopic［water activity（Aw）］ and microscopic（water molecular mobility）， which provided a theoretical basis for the determination of the safe storage moisture content. MethodAdsorption isotherm of Mume Flos decoction pieces was obtained by static weighing method， and seven common hygroscopic models were fitted and estimated. The best model was selected according to the principle that determination coefficient（R2） was closer to 1， residual sum of squares（RSS） was closer to 0 and Akaike information criterion（AIC） was smaller. According to the optimal model， the absolute and relative safe moisture contents of Mume Flos decoction pieces at 25， 35， 45 ℃ was calculated. Low-field nuclear magnetic resonance（LF-NMR） was used to measure the water molecular mobility in the hygroscopic process of Mume Flos decoction pieces. ResultThe best model to describe the adsorption isotherm of Mume Flos decoction pieces was the Peleg model. According to the model expression， the absolute safe moisture contents of Mume Flos decoction pieces at 25， 35， 45 ℃ were 9.59%， 7.96% and 7.68%， and the relative safe moisture contents were 13.05%， 11.99%， 11.77%， respectively. Mume Flos decoction pieces all contained two water states during the process of hygroscopic absorption at different temperatures， namely bound water T21 and free water T22. During the process of hygroscopic absorption， bound water had the largest increase in peak area. The sum of peak areas of the bound water and free water had a good linear relationship with the moisture contents， and the R2 were 0.959 9， 0.911 8 and 0.974 7 at 25， 35， 45 ℃， respectively. When Aw<0.57， T21 did not change， and the water molecular mobility remained unchanged. When Aw>0.57， T21 showed an increasing trend， and the water molecular mobility increased. The moisture contents of Mume Flos decoction pieces were 8.44%， 6.81% and 6.25% when the water molecular mobility increased at 25， 35， 45 ℃， respectively. ConclusionCombined with the theory of water activity and water molecular mobility， 6.25% is recommended as the safe storage moisture content of Mume Flos decoction pieces， this study can provide reference for determining the safe storage moisture content of other decoction pieces.
