title: Sub-critical water extraction of residual green tea to produce a roasted green tea-like extract.
abstract: In this study, we investigated the effects of various temperatures between 140 to 260 degrees C during sub-critical water extraction of residual green tea in making a roasted green tea-like extract, a popular beverage in Japan. Each residual green tea extract was analyzed for sensory properties and antioxidative activities, and this revealed 140 degrees C to be the best extraction temperature. 5-Hydroxymethyl-2-furaldehyde, (+)-catechin, and (-)-epicatechin were found to be the major antioxidative compounds in the 140 degrees C extract, along with theanine and some important amino acids.
authors.affiliation: Faculty of Agriculture, Shizuoka University, Japan. acheto@agr.shizuoka.ac.jp
authors.forename: Hideo
authors.initials: H
authors.lastname: Etoh
authors.forename: Naoko
authors.initials: N
authors.lastname: Ohtaki
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kato
authors.forename: Aditya
authors.initials: A
authors.lastname: Kulkarni
authors.forename: Akio
authors.initials: A
authors.lastname: Morita
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000975:Antioxidants / Q000494:pharmacology; D001628:Beverages; D002392:Catechin / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D004304:Dosage Forms; D005662:Furaldehyde / Q000031:analogs & derivatives; D007564:Japan; D013662:Tea / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000032:analysis* / Q000737:chemistry
chemical_list: D000596:Amino Acids; D000975:Antioxidants; D004304:Dosage Forms; D013662:Tea; D014867:Water; C008046:5-hydroxymethylfurfural; D002392:Catechin; D005662:Furaldehyde