The bitter orange flowers concrete is obtained by extraction with hexane or light petroleum with a yield that ranges between 0.2-0.3 per cent for the flowers harvested in spring. The extractors used are the classical static type, with a load of 1000-2000L. The yields from the flowers obtained in Autumn are higher; up to the 0.4 per cent. These are slightly higher for the flowers harvested in the morning hours, than for those harvested in the afternoon, and for the flowers extracted immediately after the harvest than those stored for several hours. Moreover, dipping the flowers in the solvent at different times gives a higher yield than one single extraction, even if prolonged. The chemical composition of concretes, as that of the essential oil, is influenced by the period of blooming, by the physical state of the flowers, by time between harvest and extraction of the flowers.
From the concrete it is possible to obtain the bitter orange flower absolute by using conventional methods for the absolutes (extraction with alcohols, winterization, filtration and concentration). The yields is of about 48—52 per cent. The bitter orange flower absolute presents a persistent odour that reseamble the fresh flowers note, more than the neroli oil does (Naves, 1970).
Was this article helpful?