title: Stability of carotenoids, phenolic compounds, ascorbic acid and antioxidant capacity of tomatoes during thermal processing.
abstract: In the present investigation we ascertained the stability of lycopene, beta-carotene, ascorbic acid, polyphenolic compounds and total antioxidant capacity (AC) during the process of concentrating tomatoes into two tomato pastes (10 and 15 degrees Brix). Thermal processing increased the content of lycopene, total phenolic compounds, total flavonoids, and the individual phenolic compounds quercetin, rutin, chlorogenic and cafeic acids, whereas it decreased the other analysed compounds. However, lycopene in the 15 degrees Brix-tomato paste decreased due to the extension of thermal processing, which led to degradation. The AC of aqueous and organic extracts was measured and different AC values were observed depending on the antioxidant profile of the extract and assay used (TEAC and FRAP). AC expressed in dry matter decreased as result of ascorbic acid losses. Overall, thermal processing enhanced the nutritional value of tomatoes, mainly by increasing the lycopene and phenolic antioxidants, but the extension of treatment must be controlled to prevent lycopene degradation.
authors.affiliation: Departamento de Tecnología de los Alimentos, Nutrición y Bromatología, Facultad de Veterinaria de la Universidad de Murcia, Murcia, España.
authors.forename: K
authors.initials: K
authors.lastname: Jacob
authors.forename: F J
authors.initials: FJ
authors.lastname: Garcia-Alonso
authors.forename: G
authors.initials: G
authors.lastname: Ros
authors.forename: M J
authors.initials: MJ
authors.lastname: Periago
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D001205:Ascorbic Acid / Q000032:analysis*; D002338:Carotenoids / Q000032:analysis*; D005511:Food Handling / Q000379:methods*; D006358:Hot Temperature; D018551:Solanum lycopersicum / Q000737:chemistry* / Q000378:metabolism; D009753:Nutritive Value; D010636:Phenols / Q000032:analysis*; D013997:Time Factors
chemical_list: D000975:Antioxidants; D010636:Phenols; D002338:Carotenoids; D001205:Ascorbic Acid