Moisture migration analysis of Chinese naked oat during different storage conditions by sorption isotherm model and low‐field NMR

Food Science & Nutrition

Huan Li¹  Bowen Li¹  Nan Zhao¹  Xing Yu¹  Xin Huang²  Lifang Cao³  Yanfeng Wang³ 

[1] Bioenergy and Environment Science & Technology Laboratory College of Engineering China Agricultural University Beijing China;National Engineering Laboratory for Crop Efficient Water Use and Disaster Mitigation Key Laboratory of Dryland Agriculture and Key Laboratory for Prevention and Control of Residual Pollution in Agricultural Film Ministry of Agriculture and Rural Affairs Beijing China;Yellow River Conservancy Technical Institute Kaifeng China;

关键词: adsorption;    bound water;    crop;    desorption;    free water;    moisture content;   

DOI  :  10.1002/fsn3.1461

来源: DOAJ

【 摘 要 】

Abstract Moisture migration is considered to be one of the most important influencer on crop quality during storage, which is easily affected by storage conditions, such as ambient humidity and temperature. The aim of this work was to determine the effect of storage condition on moisture content of Chinese naked oat by simulating 9 equilibrium relative humidity (ERH) and 5 temperatures. The equilibrium moisture content (EMC) of dry sample was achieved by adsorption, while EMC of wet one was achieved by desorption. EMC of oat increased with the increase in ERH and decreased when temperature increased. The sorption isotherm was a typical “S” shape and fitted using current EMC/ERH models. Modified Chung–Pfost (MCPE) model was the most suitable for describing the dynamic sorption process of Chinese naked oat during storage with a ERH range from 10% to 90%. There was an obvious hysteresis between adsorption and desorption isotherms, whose range decreased with the increase of temperature. High temperature accelerated moisture migration by increasing the hydrophilicity of oat surface. Moreover, dynamic moisture migration was imaged by low‐field nuclear magnetic resonance (NMR), showing that moisture migrated between ambient environment and oat mainly through endosperm where most moisture accumulated. During sorption, free water migrated firstly, followed by bound water and the change in content of bound water was more stable than that of free water. The results of this study can provide a useful information for future work on quality control of oat during storage.

【 授权许可】

Unknown