Effects of infusion time and addition of milk on content and absorption of polyphenols from black tea

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92 Citations (Scopus)

Abstract

Epidemiological studies assessing the health benefits of drinking black tea are equivocal. Such disparity may reflect an inability of semiquantitative assessment to consider how infusion time and addition of milk affect the bioavailability of potentially beneficial antioxidant polyphenols. Six brands of tea demonstrated similar increases in antioxidant capacity and total phenolic and catechin contents with increasing infusion time. These results were unaffected by the addition of milk. Consumption of black tea (400 mL) was associated with significant increases in plasma antioxidant capacity (10%) and concentrations of total phenols (20%), catechins (32%), and the flavonols quercetin (39%) and kaempferol (45%) (all p < 0.01) within 80 min. This was unaffected by adding milk. Infusion time may therefore be a more important determinant in the absorption of polyphenols from black tea. Observational studies assessing the health benefits of tea consumption require recording of brewing methods as well as frequency of consumption.

Original languageEnglish
Pages (from-to)4889-4894
Number of pages6
JournalJournal of Agricultural and Food Chemistry
Volume55
Issue number12
Early online date10 May 2007
DOIs
Publication statusPublished - 13 Jun 2007

Keywords

  • black tea
  • polyphenols
  • flavonoids
  • catechins
  • antioxidant capacity
  • infusion time
  • absorption
  • milk
  • total antioxidant capacity
  • heart-disease
  • dietary flavonoids
  • total phenol
  • plasma
  • consumption
  • health
  • humans
  • green
  • assay

Cite this

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title = "Effects of infusion time and addition of milk on content and absorption of polyphenols from black tea",
abstract = "Epidemiological studies assessing the health benefits of drinking black tea are equivocal. Such disparity may reflect an inability of semiquantitative assessment to consider how infusion time and addition of milk affect the bioavailability of potentially beneficial antioxidant polyphenols. Six brands of tea demonstrated similar increases in antioxidant capacity and total phenolic and catechin contents with increasing infusion time. These results were unaffected by the addition of milk. Consumption of black tea (400 mL) was associated with significant increases in plasma antioxidant capacity (10{\%}) and concentrations of total phenols (20{\%}), catechins (32{\%}), and the flavonols quercetin (39{\%}) and kaempferol (45{\%}) (all p < 0.01) within 80 min. This was unaffected by adding milk. Infusion time may therefore be a more important determinant in the absorption of polyphenols from black tea. Observational studies assessing the health benefits of tea consumption require recording of brewing methods as well as frequency of consumption.",
keywords = "black tea, polyphenols, flavonoids, catechins, antioxidant capacity, infusion time, absorption, milk, total antioxidant capacity, heart-disease, dietary flavonoids, total phenol, plasma, consumption, health, humans, green, assay",
author = "Kyle, {Janet A. M.} and Morrice, {Philip C.} and Geraldine McNeill and Duthie, {Garry G.}",
year = "2007",
month = "6",
day = "13",
doi = "10.1021/jf070351y",
language = "English",
volume = "55",
pages = "4889--4894",
journal = "Journal of Agricultural and Food Chemistry",
issn = "0021-8561",
publisher = "American Chemical Society",
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TY - JOUR

T1 - Effects of infusion time and addition of milk on content and absorption of polyphenols from black tea

AU - Kyle, Janet A. M.

AU - Morrice, Philip C.

AU - McNeill, Geraldine

AU - Duthie, Garry G.

PY - 2007/6/13

Y1 - 2007/6/13

N2 - Epidemiological studies assessing the health benefits of drinking black tea are equivocal. Such disparity may reflect an inability of semiquantitative assessment to consider how infusion time and addition of milk affect the bioavailability of potentially beneficial antioxidant polyphenols. Six brands of tea demonstrated similar increases in antioxidant capacity and total phenolic and catechin contents with increasing infusion time. These results were unaffected by the addition of milk. Consumption of black tea (400 mL) was associated with significant increases in plasma antioxidant capacity (10%) and concentrations of total phenols (20%), catechins (32%), and the flavonols quercetin (39%) and kaempferol (45%) (all p < 0.01) within 80 min. This was unaffected by adding milk. Infusion time may therefore be a more important determinant in the absorption of polyphenols from black tea. Observational studies assessing the health benefits of tea consumption require recording of brewing methods as well as frequency of consumption.

AB - Epidemiological studies assessing the health benefits of drinking black tea are equivocal. Such disparity may reflect an inability of semiquantitative assessment to consider how infusion time and addition of milk affect the bioavailability of potentially beneficial antioxidant polyphenols. Six brands of tea demonstrated similar increases in antioxidant capacity and total phenolic and catechin contents with increasing infusion time. These results were unaffected by the addition of milk. Consumption of black tea (400 mL) was associated with significant increases in plasma antioxidant capacity (10%) and concentrations of total phenols (20%), catechins (32%), and the flavonols quercetin (39%) and kaempferol (45%) (all p < 0.01) within 80 min. This was unaffected by adding milk. Infusion time may therefore be a more important determinant in the absorption of polyphenols from black tea. Observational studies assessing the health benefits of tea consumption require recording of brewing methods as well as frequency of consumption.

KW - black tea

KW - polyphenols

KW - flavonoids

KW - catechins

KW - antioxidant capacity

KW - infusion time

KW - absorption

KW - milk

KW - total antioxidant capacity

KW - heart-disease

KW - dietary flavonoids

KW - total phenol

KW - plasma

KW - consumption

KW - health

KW - humans

KW - green

KW - assay

U2 - 10.1021/jf070351y

DO - 10.1021/jf070351y

M3 - Article

VL - 55

SP - 4889

EP - 4894

JO - Journal of Agricultural and Food Chemistry

JF - Journal of Agricultural and Food Chemistry

SN - 0021-8561

IS - 12

ER -