Molecular Mobilities of Instant Starch Gels Determined by Oxygen‐17 and Carbon‐13 Nuclear Magnetic Resonance

The molecular mobility of both the water component and the starch component of three instant starches was determined by proton decoupled oxygen‐17 (¹⁷O) and proton decoupled carbon‐13 (¹³C) Nuclear Magnetic Resonance (NMR) spectroscopy. The effect of starch concentration and various storage conditions were studied. The molecular mobility of the water associated with each of the instant starches over all concentrations studied as measured by ¹⁷O NMR transverse relaxation rates was not much slower than that of free or bulk water. The effect of storage conditions on the molecular mobility and conformation of the starches, as monitored by proton decoupled ¹⁷O and ¹³C NMR, was in most cases small, despite the observed differences in retrogradation among the starches.