Rapid, accurate, and simultaneous measurement of water and oil contents in the fried starchy system using low-field NMR

•Water and oil contents in fried starch were concurrently determined by LF-NMR.•The oil and water signals were verified by desiccation at 105°C.•There was no superposition between the oil and water signals in fried starch.•Oil content determined by LF-NMR was more accurate than that of Soxhlet extraction. Fried starchy food is rich in oil that may pose a risk to health. For controlling of the oil uptake, a rapid and accurate method for the determination of oil content in the fried starchy food is important. In this study, low-field nuclear magnetic resonance (LF-NMR) was applied to simultaneously determine water and oil contents in the model fried starchy system. The proton signals from oil and water were verified and distinguished by desiccation at 105°C. There was no superposition between oil and water signals in the fried starch, making it possible for quantitative analysis of water and oil in a single test. Compared with Soxhlet extraction, the LF-NMR analysis provided a more accurate result of oil content in the fried starchy system, confirming the practicability of the application of LF-NMR technology as a fast and accurate method for the quantification of water and oil in the fried starchy system.