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.