Determination of supplemental feeding needs for astaxanthin and canthaxanthin in salmonids by supramolecular solvent-based microextraction and liquid chromatography-UV/VIS spectroscopy

► A microextraction method for determining carotenoids in farming salmonids is proposed. ► The extractant used is a supramolecular solvent made up of decanoic acid assemblies. ► Method assets are high sample throughput, environmental friendliness and low cost.