Abstract:

The main characteristic peaks of linolenic, linoleic, oleic acid, saturated fatty acids and water in vegetable oils
were analyzed by 1H-NMR spectroscopy. Benzoic acid was selected as an internal standard to quantify the contents of
linolenic, linoleic, oleic acid, saturated fatty acids and water in vegetable oils by this method without any pretreatment. The
recoveries were 98%–102% with RSD of 0.11%, 0.12%, 0.68%, 0.70% and 2.65% for linolenic, linoleic, oleic acid, total
saturated fatty acids and water, respectively. The contents of linolenic, linoleic, oleic acid, total saturated fatty acids and
water can be determined directly and accurately with less sample consumption and without using expensive standards. This
new method is simple and applicable for studying quality standards for vegetable oils.

Key words: nuclear magnetic resonance (NMR), unsaturated fatty acid, saturated fatty acids, water