Physicochemical and functional properties of the cold press lemon, orange, and grapefruit seed meals

The aim of this study was to evaluate physicochemical and functional properties of the defatted cold press meals of lemon, orange and grapefruit seeds. Proximate composition, viscosity, colour, flavonoid and phenolic acid compositions, and functional properties (water and oil holding capacity, emulsion and foaming properties and least gelling concentration) were determined. It was shown that the meals are high in protein, but low in phytic acid. Their colour is usually light yellow-red, and compatible for most food products. These meals were very good sources of citrus flavonoids (eriocitrin, rutin, naringenin, etc.) and phenolic acids. Hence, they can be used in functional food products or be utilised as source for flavonoid extraction. Furthermore, the meals were very good in water holding capacity, and moderately good in emulsification and foaming properties to be used as food ingredients. Citrus seed press meals could be valorised in food products or in extracting fine chemicals.