Assessment of the Physicochemical Properties and Oxidative Stability of Kernel Fruit Oil from the Acrocomia totai Palm Tree

Abstract

AbstractThis study investigated the effects of variations in oil contents and fatty‐acid composition, density, viscosity, acid values, saponification values, specific oxidative stability, and antioxidant concentration of Acrocomia totai kernel oil during fruit maturation. Fatty acids were quantified using 1H nuclear magnetic resonance (NMR) spectroscopy, gas chromatograph‐flame‐ionization detector (GC‐FID), and Fourier transform Raman (FT‐Raman) spectroscopy analyses. The results showed that all physicochemical characteristics and oil composition changed during the ripening stage. The CG‐FID analysis showed a reduction in the unsaturated fatty‐acid content (from 78.8% to 22.1%), with a proportional increase in the saturated fatty‐acid contents (from 21.6% to 77.9%). The difference in the fatty‐acid composition was confirmed by analysis of the 1H NMR and FT‐Raman spectra. The degree of unsaturation was calculated to determine the oxidative stability of oil. These results suggest that the fruit's maturation contributes to the specific oxidative stability. The antioxidant concentration revealed higher contents of carotenoids in the ripe fruit (0.16 mg of carotenoid per 100 gKERNEL) when compared to the unripe fruit (0.05 mg of carotenoid per 100 gKERNEL). In the total phenolics analysis, there was no change in concentration over ripening time. These results show that kernel oil has physicochemical properties comparable with high‐quality commercial vegetable oils, suggesting that it is a promising alternative to conventional vegetable oils.