title: Caffeine and total polyphenol contents of market tea cultivated and processed in Bangladesh.
abstract: OBJECTIVE
  The aim of this study was to determine the contents of caffeine and total polyphenol in six brands of market tea cultivated and processed in Bangladesh.
  
  
  METHODS
  Caffeine and polyphenol contents were determined by solvent extraction (AACC) and the International Organisation for Standardisation Method (ISO) 14502-1 respectively.
  
  
  RESULTS
  Caffeine contents of the different tea samples ranged between 0.99 +/- 0.17% to 2.08 +/- 0.16% (g/100g materials), while that of total polyphenol was from 36.90 +/- 1.39% to 17.29 +/- 2.30% of gallic acid equivalents (GAE). The order of caffeine concentration in tea samples was found as follows: Organic Black Tea > Taaza Tea > Organic Green Tea > Magnolia Tea > Organic Zinger Tea > Organic Tulsi Tea. The polyphenol concentration in the tea samples was highest in Organic Green Tea followed by Taaza Tea and the rest as follows: Magnolia Tea > Organic Black Tea > Organic Zinger Tea > Organic Tulsi Tea. An indicative difference in amounts of caffeine and polyphenols for different tea brand samples is seen in this study.
  
  
  CONCLUSIONS
  This systematic screening provides information to producers as well as consumers on the quantities of caffeine and polyphenols in commercial tea available in the markets of Bangladesh.
authors.forename: Islam G M
authors.initials: IG
authors.lastname: Rabiul
authors.forename: Uddin M
authors.initials: UM
authors.lastname: Gias
authors.forename: Rahman M
authors.initials: RM
authors.lastname: Mahfuzur
authors.forename: A
authors.initials: A
authors.lastname: Yousuf
mesh_terms: D001459:Bangladesh; D002110:Caffeine / Q000737:chemistry*; D005504:Food Analysis / Q000379:methods* / Q000706:statistics & numerical data; D059808:Polyphenols / Q000737:chemistry*; D013662:Tea / Q000737:chemistry*
chemical_list: D059808:Polyphenols; D013662:Tea; D002110:Caffeine