Carotenoid extraction methods: A review of recent developments

- Leafy vegetables, fruits, and microalgae are the rich source of carotenoids.
- The choice of solvent is the most critical for efficient extraction of carotenoids.
- Soxhlet extraction is a conventional method delivers the highest yield of carotenoids.
- Supercritical fluid extraction is the superior “green” method for the carotenoids.
- Green extraction needs further methodological and technological advancements.

The versatile use of carotenoids in feed, food, cosmetic and pharmaceutical industries has emphasized the optimization of extraction methods to obtain the highest recovery. The choice of method for carotenoid extraction from food matrices is crucial, owing to the presence of diverse carotenoids with varied levels of polarity, and the presence of various physical and chemical barriers in the food matrices. This review highlights the theoretical aspects and recent developments of various conventional and nonconventional methods used for the extraction of carotenoids, including ultrasound-assisted extraction (UAE), pressurized liquid extraction (PLE), and supercritical fluid extraction (SFE). Recent applications of non-toxic and environmentally safe solvents (green solvents) and ionic liquids (IL) for carotenoid extraction are also described. Additionally, future research challenges in the context of carotenoids extractions are also identified.