By-products from different citrus processes as a source of customized functional fibres

Dietary fibre encompasses a huge variety of macromolecules, exhibiting a wide range of physicochemical properties. Citrus fibre can be obtained from different industrial sources and different kinds of citrus. The chemical components of fibre (pectin, lignin, cellulose and hemicellulose), together with other compounds, such as flavonoids, were analysed in nine different industrial sources. Final fibre composition was more dependent on the industrial process than on the type of citrus. The chemical changes gone by citrus fibre showed losses of functional values; i.e. soluble dietary fibre and ascorbic acid content decreased when waste products were transformed into fibres. The water-holding and lipid-holding capacities of analysed citrus fibres suggested a non-linear behaviour of these properties for the analysed citrus fibres.