Comparative Study of the Physicochemical Properties and Nutritional Quality of Argan Oil from Endemic and Planted Argania spinosa (L.) Fruit Trees in South-West Algeria

Argania spinosa tree, notoriously famous for its primary product, the argan oil, is a versatile agroforestry tree that grows wild in Algeria and Morocco. However, recent cultivation efforts have been undertaken in Algeria to protect the species and valorize the local productions of argan oil. Hence, a comparative study was conducted on cold-pressed oils from endemic and planted argan trees, located respectively in Tindouf and Adrar provinces of Southwestern Algeria, to evaluate the impact of plantation on argan oil quality. For each area, three samples of argan oil were produced and analyzed by three analytical replicates. According to the Moroccan guidelines, both products were extra-virgin oils due to favorable saponification indices, free acidities, peroxide values and UV exams. Their fatty acid composition and sterol profile were similar, with high levels of unsaturated fatty acids and peculiar phytosterols beneficial to consumer health. However, the cultivation of A. spinosa affected the amounts of tocopherols, total polyphenols and carotenes, squalene, and inorganic elements, which were generally lower in the oil from Adrar than in that from Tindouf. These differences may be related to the different pedoclimatic and agronomic contexts of growth and did not affect the quality and marketability of argan oil. Overall, this study provides preliminary evidence of the feasibility of cultivating A. spinosa outside its natural biotope in hyper-arid Algerian regions, producing high-quality oil that could play a crucial socio-economic role in the national economy. However, further studies involving multiple cultivation environments and long-term agronomic and ecological assessments are required to better understand the performance of A. spinosa under non-native growing conditions.