1H and 13C NMR investigation of oils extracted from exotic fruits

Exotic fruit seeds are waste of industrial preparation of foods and human consumption. The contents in terms of nutrients of oils extracted from exotic fruit seeds are not fully understood, and they remain object of study. We propose a practical, inexpensive, qualitative and quantitative approach based on the use of 1H and 13C NMR spectroscopy for the fatty acid chain profiling of these oils. The composition of eleven seed oils was investigated. The amounts of linoleic (from 3.5% in Rambutan to 84.6% in Feijoa), oleic (from 6.9% to 68.7% in Papaya), and saturated fatty acid chains (from 7.9% in Feijoa to 49.5% in Rambutan) were determined. The total contents of unsaturated fatty acid (MUFA and PUFA) chains in oils ranged from 37.5% in Mangosteen to 91.5% in Feijoa. The oils were characterized by saturated/unsaturated (SFA/PUFA) ratios ranging from 0.08 to 1.07, with values which were superior to that commonly reported for extra virgin olive oil. These ratios are potentially favorable for human health. The ANOVA test showed the model to be remarkably significant (p < 0.05). Spectral data agreed those reported in the literature for conventional methods. Although linolenic acid was not detected in all oils, their fatty acid chain profiles make them desirable in terms of nutrition and as alternative energy sources.