Lipidic composition and thermal stability of oils from Dipteryx alata, Acrocomia totai, Mauritia flexuosa and Caryocar brasiliense

Vegetable oils have various types of applications, one of which is food. Dipteryx alata ("baru" or tonka bean) and Acrocomia totai ("bocaiuva", or macaw palm) nuts, Mauritia flexuosa ("buriti", or buriti palm), and Caryocar brasiliense ("pequi", or pequi fruit) pulps are sources of unsaturated lipids. By performing quality, identity, and stability analyses, it is possible to check whether these oils are proper for human nutrition. Oils of tonka bean and pequi fruit had acceptable acidity values, while macaw palm oils had values ​​above those allowed by the Codex Alimentarius. The peroxide index was within the recommended value in all samples. In addition, the refractive index and relative density were similar for all oils. The coloring indicated the possible presence of chlorophyll in tonka bean and macaw palm oils, and carotenoids in buriti palm and pequi fruit oils. The fatty acid profile revealed that macaw palm, buriti palm, and pequi fruit oils are mostly monounsaturated, while A. totai oil exhibited a predominantly saturated profile. The nutritional quality indices demonstrated that the oil with the most similar quality to olive oil was that of buriti palm. UV-vis and fluorescence analysis indicated that pequi fruit and buriti palm oils contain beta-carotene, while tonka bean and macaw palm oils have alpha-tocopherol. Finally, thermal analyses showed that tonka bean and buriti palm oils have the highest stability at high temperatures, indicating the best potential for culinary use.