Natural betalain chromophores, extracted from bougainvillea flowers, were stabilised on different surfaces
of g-alumina matrices. This strategy was used to produce a family of hybrid pigments including one
yellow and several purple hues. Both textural and structural parameters of g-alumina were identified as
important factors to stabilise the chromophores. Particularly, a high amount of coordinative unsaturated
sites of aluminium, high surface specific areas and pore diameters as high as 15 nm are suitable to
stabilise the purple chromophores.