Monitoring and modelling of moisture content with nuclear magnetic resonance (NMR)

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2022-11-04
Selçuk, Burak
The aim of this study is to observe the variation of the moisture content and drying rate over time, temperature, and position. Chickpea puree, eggplant, and apple were selected for drying, and the drying experiments were performed at 50-70°C for 3 h. The moisture content of samples was measured using oven, time-domain nuclear magnetic resonance (TD-NMR), and magnetic resonance imaging (MRI) methods. The changes in moisture content and drying rate with temperature and position were monitored. The drying rate of chickpea drying was 0.34-0.44 kgH2O/m2h and the drying time was estimated as 440-320 min depending on the drying temperature and position. The drying rate of eggplant drying was 0.38-0.62 kgH2O/m2h and the drying time was estimated as 460-280 min depending on the drying temperature and position. The drying rate of apple drying was 0.65-0.99 kgH2O/m2h and the drying time was estimated as 420-260 min depending on the drying temperature and position. It was concluded that TD-NMR and MRI methods were effective, high-sensitive and precise in estimating moisture content during drying process.

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Citation Formats
B. Selçuk, “Monitoring and modelling of moisture content with nuclear magnetic resonance (NMR),” M.S. - Master of Science, Middle East Technical University, 2022.