Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The influence of organic acid and heating treatments on carotenoid degradation on a simulated cashew apple juice was assessed by high performance liquid chromatography coupled with a photodiode array and mass spectrometry detectors. A total of nineteen carotenoids were separated in unheated simulated cashew apple juice, with all-trans-beta-cryptoxanthin and all-trans-beta-carotene as the major ones. As a consequence of heating, five xanthophylls disappeared, whereas two new cis isomers and five epoxide or furanoid-derivatives were formed and the levels of all cis isomers increased. In addition, 12'-apo-beta-carotenal was formed at 90 degrees C. Two oxidation compounds (12'-apo-beta-carotenal and 5,6-epoxy-beta-cryptoxanthin) were formed after beta-cryptoxanthin heating at 90 degrees C in an aqueous-based system. In all systems, the amounts of total carotenoids lost were not compensated by those formed. These facts indicated that isomerisation and oxidation to both coloured and non-coloured compounds were the main reactions occurring during heating of carotenoids in aqueous-based and juice systems. (C) 2009 Elsevier Ltd. All rights reserved.11712834Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)