Abstract
Considered for a long time as debris, citrus seeds and their components deserve further investigation and valorisation. Relatively few studies have yet examined the oil extracted from citrus seeds. The objective of this work is to identify the constituents of citrus seed oils in order to valorise them, notably for the least exploited species; the bigarade orange. Four citrus species were studied: Lemon, sweet orange (Maltese), Grapefruit and Bigarade (bitter Orange). Different parameters were measured: oil content, fatty acids composition, the percentage and the different compounds of the unsaponifiable fraction. The analysis of total lipid showed a high content of citrus seed oil (44.56%). This value is higher than those obtained in some industrial plants such as cotton and maize seeds. Hence, Citrus seeds are considered oleaginous. The fatty acid profile showed that citrus seed oil contains eight fatty acids including three major acids: linoleic (C18: 2cis w6), oleic (C18: 1) and palmitic (C16: 0) acids. Results also showed that Citrus oils are highly unsaturated (71.58%), therefore of very good quality. This study showed the richness of these oils in omega 6 (C18: 2cis omega 6) and omega 3 (C18: 3 omega 3). Bigarade species revealed a high rate of the unsaponifiable fraction and a high number of bands compared to other species.