Tea chemistry

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Tea chemistry

• Barbora Klanicová
• Tomáš Fójcik

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Some facts about tea

• The plant is called Camellia sinensis
• Is grown in 30 countries and consumed worldwide
• 3 basic forms green tea
• black tea
  oolong

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Cultivation of tea

• Normal height about 1 metre
• Tea requires ? abundant rainfall and sunshine
• ? acid soil
• ? high altitude from
  sea level to about 2000 m

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Tea manufacture

• Processing - cut, tear and curl
• Fermentation - process of oxidation
• Drying - to arrest fermentation
• Sorting - cleaning and grading over
  electrostatic fibre extractors
• Packing - into paper sacks for export

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Tea chemistry

• Caffein Chlorophyll
• Tea contains Mn, Zn, K, Mg and no carbohydrates
  or fats
• Is rich in fluoride (green tea twice more than
  black tea)
• Caffein ? soluble in boiling water ?
  one cup 40 mg ( less than half in a cup of
  coffee)
• Chlorophyll ? undergoes biological decomposition
  ? same sort of parent
  structure as hemoglobin (Fe x Mg)

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Tea chemistry

• Polyphenols ? carbon, oxygen, hydrogen ?
  dull weather-lower concentrationWhen tea leaves
  are ruptured during rolling, the polyphenols and
  oxidase mix and oxidation starts if oxygen is
  present.

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Tea and health

• Scientific Research on Black Tea has revealed
  that
• It enhances muscle performance It
  reduces gastric ulcer It reduces the blood
  sugar level in diabetes It modulates blood
  cholesterol Prevention of dental caries by tea
  or tea polyphenols Tea plant root extract has
  anti-tumor activity Antioxidant potential of
  tea Tea polyphenols decrease the mutagenicity
  of carcinogens

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Vocabulary

• abundant rainfall vydatný déšt
• high altitude nadmorská výška
• grading trídení
• soluble in boiling water rozpustný
• enhance zvyšovat
• gastric ulcer žaludecní vred
• dental caries zubní kaz

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Thnx 4 your attention