Flavonoids, total phenolics and antioxidant capacity: comparison between commercial green tea preparations

The potential health benefits attributed to green tea and its catechins such as antioxidant effects, cancer chemoprevention, and weight loss have led to a huge increase of green tea products in the food market. The objectives of this work were to analyze and compare these products in terms of phenol...

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Detalles Bibliográficos
Autores: Kodama,Débora Harumi, Gonçalves,Any Elisa de Souza Schmidt, Lajolo,Franco Maria, Genovese,Maria Inés
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Brasil
Institución:Sociedade Brasileira de Ciência e Tecnologia de Alimentos (SBCTA)
Repositorio:Food Science and Technology (Campinas)
Idioma:inglés
OAI Identifier:oai:scielo:S0101-20612010000400037
Acceso en línea:http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612010000400037
Access Level:acceso abierto
Palabra clave:antioxidant capacity
catechins
total phenolics
green tea
Descripción
Sumario:The potential health benefits attributed to green tea and its catechins such as antioxidant effects, cancer chemoprevention, and weight loss have led to a huge increase of green tea products in the food market. The objectives of this work were to analyze and compare these products in terms of phenolic contents and in vitro antioxidant capacity including tea bags, dehydrated leaves, and ready-to-drink preparations after standardization of the infusion preparation procedure. Total phenolics content in 1 cup of the different teas varied from 90 to 341 mg of catechin equivalents, and the highest and the lowest values were both those of the ready-to-drink products. Infusions prepared from tea bags had contents varying from 96 to 201 mg.200 mL-1, and there were no significant differences among batches. The DPPH radical scavenging and the Oxygen Radical Absorbing Capacities (ORAC) varied largely among the different tea preparations, from 23 to 131 mmoles of Trolox Equivalents (TE).200 mL-1 (DPPH), and from 1.2 to 5.1 mmoles of TE.200 mL-1 (ORAC), but again there were no differences among infusions or ready-to-drink commercial preparations. However, the antioxidant capacity of ready-to-drink products was partially due to the presence of other non-phenolic compounds such as ascorbic acid