title: Role of degradation products of chlorogenic acid in the antioxidant activity of roasted coffee.
abstract: Antioxidant activities of brewed coffees prepared from six commercial brands ranged from 63.13 ± 1.01 to 96.80 ± 1.68% at the highest levels tested. Generally, the degree of antioxidant activity of the brewed coffee was inversely proportional to the total chlorogenic acid concentration. A sample obtained from the major chlorogenic acid, 5-caffeoylquinic acid (5-CQA), heated at 250 °C exhibited potent antioxidant activity (79.12 ± 2.49%) at the level of 10 μg/mL, whereas unheated 5-CQA showed only moderate antioxidant activity (44.41 ± 0.27%) at the level of 100 μg/mL. Heat produced relatively high levels of pyrocatechol (2,809.3 μg/g) and 2-methoxy-4-vinylphenol (46.4 μg/g) from 5-CQA, and their antioxidant activity levels were 76.57 ± 3.00 and 98.63 ± 0.01%, respectively. The results of the present study suggest that roasting degrades chlorogenic acids to form potent antioxidants and thus plays an important role in the preparation of high-antioxidant low-acid coffee.
authors: Department of Environmental Toxicology, University of California , Davis, California 95616, United States.
authors: Masumi
authors: M
authors: Kamiyama
authors: Joon-Kwan
authors: JK
authors: Moon
authors: Hae Won
authors: HW
authors: Jang
authors: Takayuki
authors: T
authors: Shibamoto
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D002726:Chlorogenic Acid / Q000737:chemistry*; D040503:Coffea / Q000737:chemistry*; D003069:Coffee / Q000737:chemistry; D003296:Cooking; D008401:Gas Chromatography-Mass Spectrometry; D006358:Hot Temperature; D011801:Quinic Acid / Q000031:analogs & derivatives / Q000032:analysis; D012639:Seeds / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D003069:Coffee; C472707:caffeoylquinic acid; D011801:Quinic Acid; D002726:Chlorogenic Acid
keywords: antioxidant activity; chlorogenic acid; coffee roasting; decomposition products