EFFECT OF TEMPERATURE ON NUCLEAR SPIN-SPIN RELAXATION TIMES OF OIL PROTONS IN RAPESEED SEEDS

There was studied the influence of temperature on the values of the mass fraction of oleic acid in oil of rapeseed seeds obtained indirectly using the pulsed nuclear magnetic resonance (NMR) method. It was found that in the range from 20 to 26 °С, a change in the temperature of the analyzed seeds by 1 °С leads to a change in the value of the average spin-spin relaxation time (T2sr) of the protons of triacylglycerols (TAG) in oil, which in the developed method of determining the mass fraction of oleic acid in oil of rapeseed seeds is an analytical parameter, on average by 1.8 m/s, for the studied samples of seeds with a mass fraction of oleic acid in oil from 58 to 82 %. Based on the established regularities of temperature influence on the measured T2sr values of TAG protons, a method of temperature correction of the results of measuring the mass fraction of oleic acid in oil of rapeseed seeds by NMR method was developed, taking into account their actual temperature.