Fermentation of Tea Group F Simra Khattak Saif

Fermentation of Tea Group - 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 China. density in border of Burma and Western

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 Compressing Sorting Steaming heating/burning Rolling fermentation withering Spontaneo us oxidation Slow oxidation Final product

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: H 2 O 2 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. 2. 3. 4. • 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. Filamentous fungi Pu-erh tea Approved by FDA; GRAS Toxicity is rare , carefully treated in to prevent spore formation

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 packaging Heat and Dry compressing Secondary oxidation/fermentation Endo-oxidation(tea leaf enzymes) Aging Exo-oxidation( catalyzed by microbes) mainly Aspergillus niger

SIGNIFICANCE IN FOOD INDUSTRY (PARTICULARLY IN PAKISTAN) AND STATISTIC VALUES: Ø Beverages like tea and coffee serves to be second most famous beverage around the world, right after water. Ø They are the second largest planted crops after wheat. Ø Pakistan serves to have around 170 units operating in this very sector. Ø Contributing towards growth in upstream and downstream industries

Ø Considering data from food and agriculture organization, FAO for tea production across global market Ø 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.