fermentation of tea group - f simra khattak saif ullah khan maryam jadoon aqib javed ammarah khan...
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Fermentation of TeaGroup - F
Simra Khattak
Saif Ullah Khan
Maryam jadoon
Aqib javed
Ammarah Khan
Nawal daud
Afifa Maryam
A night before exam
Yes, your guess is right
After taking tea
What is tea?
Aromatic beverage commonly prepared by pouring boiling water over leaves of plant, Camellia sinensis.
Tu in Chinese, Cha in Bengali, Chai in Urdu. tea plants are native to Asia Highest density in border of Burma and Western
China.
Types of tea
Hundreds of types of tea,
based upon different recipes.
Tea processing methods are different.
Basic difference
All kind of tea, are prepared by from plant, Camellia sinensis.
3 major classes, based upon extent of fermentation
Green, yellow, Black.
Least fermented- mildly fermented- highly fermented.
Why fermentation is required.
Preservation:
Antimicrobial agents
Taste:
Astringency is removed
Flavor:
Polyphenol
Aroma:
Volatile organic compounds
Biochemistry of Tea
Health and therapeutic advantages
Anti- oxidant activity of flavonoids (Ryan and Sutherland, 2011)
Reduces oxidative damage (khan et al, 2005)
Anti-cancer properties( Shukla and Taneja 2002)
Reduces atherosclerosis. (Vinson et al, 2004)
Anti-inflammatory properties (Nag Chaudhuri et al. 2005)
Maintenance of dental health. (Simpson et al. 2001)
Maintenance of bone health ( Hegarty et al, 2001)
Generalized process flow diagram
Hand picking Sorting heating/burning Rolling
witheringfermentationSteaming
Compressing
Slow oxidationFinal product
Spontaneous
oxidation
Optimum conditions
Types of teas actually vary from different fermentation procedures, each of which having its own optimal conditions.
1.Green tea: (Fairley and Swaine, 1975)
Ph: 4.3-5.6
Temperature: 5°-30°C
Initiating Agent: H2O2 suspension.
2.Black tea: (Robert and Woods)
PH: 5-6
Temperature: 25°C
Fermentation, Supreme step of process
All the hundred different types of tea have common steps of tea processing, but they only differ in FERMENTATION step.
Fermentation gives tea, its characteristic features.
• Quality (type)
• Aroma
• Taste
• Flavor
Selected types of tea
Kombucha tea
Pu-erh tea
Microbes being used in fermentation
Aspergillus Niger (Pu-erh tea) Saccharomyces cerevisiae (kombucha tea)
1. Filamentous fungi2. Pu-erh tea3. Approved by FDA; GRAS4. Toxicity is rare ,carefully treated in to
prevent spore formation
• the budding yeast commonly known as brewing yeast
• used to make bread, wine, beer and kombucha tea
• Favors aerobic fermentation in high concentrations of sugar ,tolerate high concentrations of ethanol.
Kombucha, brief description
Effervescent fermented tea.
Can be black or green.
It has many health benefits
Kombucha
Ingredients:
A starter culture which is kombucha (already brewed) or vinegar.
scoby (kombucha mushroom)
Tea, green or black.
Organic sugars such as molasses
process
kombucha
Biochemical process
1.• Alcohol formation from
sugar
2.• acid formation from
nutrients and alcohol.
Pu-erh tea, brief description
Pu-erh is a microbially fermented tea.
Pu-erh undergoes solid-state fermentation
The key organism found and responsible for almost all pu-erh fermentation is Aspergillus niger.
Longer the aging, more expensive and flavoursome.
Pu-erh tea
Process:
Take tea leaves
Heat and Dry Secondary oxidation/fermentation
Endo-oxidation(tea leaf enzymes)
Exo-oxidation( catalyzed by
microbes) mainly Aspergillus niger
Agingcompressingpackaging
SIGNIFICANCE IN FOOD INDUSTRY (PARTICULARLY IN PAKISTAN) AND STATISTIC VALUES:
Beverages like tea and coffee serves to be second most famous beverage around the world, right after water.
They are the second largest planted crops after wheat.
Pakistan serves to have around 170 units operating in this very sector.
Contributing towards growth in upstream and downstream industries
Considering data from food and agriculture organization, FAO for tea production across global market
While considering data from Federal Bureau of statistics, Government of Pakistan, average import of tea in recent last years is around as follows.
In the recent years, along with tea, coffee consumption has been markedly increased. This can be visualized
from following statistic data from ICO.