T E A C O M P O S I T I O N
Tea is the ultimate master of chemical diversity. Over 30,000 polyphenols are found in a tea plant.
Here, we discuss the major contributors to why tea is unique compared to other plants.
Polyphenols are naturally occurring compounds in plants. They are responsible for the protection of the plants against UV, herbivores, and pests. There are many types of polyphenols but the 4 major divisions are: phenolic acids, flavonoids, stilbenes, and lignans.
Flavonoids are the most studied group of polyphenols. They are also the most abundant polyphenols on the planet. The quality of the flavonoids affects the taste, quality, and the health of teas.
Catechins and quercetin are two of flavonoids found in tea. Catechins make up to 27% of flavonoids in tea.
Tannins, theaflavins and thearubigins are polyphenols present in tea leaves.
Tea is one of the richest catechin sources and contains the major catechin, (−)-epigallocatechin-3-gallate (EGCG) which has many beneficial properties for human health such as anticancer, anti-obesity, antidiabetic, anticardiovascular, anti-infectious, hepatoprotective, and neuroprotective effects
Amino acids are important molecules that contribute to the variability in the quality of the finished tea - whether it will have "hui gan" (short bitterness followed by a lingering slight sweetness); or "umami" (the savory taste that reminds you of meat).
There are 2 types of amino acids in tea plant: amino acids from protein and non-protein amino acids
Non-protein amino acids or free amino acids are the most beneficial to tea as a beverage.
L - Theanine is the most abundant free amino acid which accounts for 60%-70% of the total free amino acids in tea. It is naturally unique to tea plants and thought to be responsible for the calming effect of tea without drowsiness.
Another beneficial free amino acid in tea is the GABA (γ-aminobutyric acid) which also has stress-reducing abilities that may improve mental focus.
Tryptophan, glutamine, asparagine are some of the free amino acids that can be found in the tea leaves.
Have you heard of the term "RELAXED ALERTNESS"? This is one of the advantages of drinking tea over other caffeinated beverages. Tea is the only consumable plant that possesses compound that can bring about relaxed alertness.
Enzymes are an important component in plant growth. It helps break down large molecules of nutrients in the soil so that roots can absorb them and transport them to the leaves where plant's food production takes place. Inside the undamaged and living cells, enzymes are necessary to create amino acids.
In the tea plants, enzymes are helpful in creating different types of tea.
Enzymes such as polyphenol oxidase and peroxidase are oxidative enzymes that convert catechins into theaflavins in black tea. Further oxidation of theaflavins will result to the formation of thearubigins.
Did you know that you can use black tea to clean surfaces?
Theaflavin is flavanol that has showed potential as an antibacterial agent, which activity shown against many species of bacteria.
(Commonly known as CAFFEINE
A natural compound found in over 60 plants. The scientific name for theine is METHYLXANTHINE, which is commonly known as caffeine.
Fresh tea leaves approximately contains 2–5% caffeine. Tea also contains much smaller quantities of theobromine and theophyline
Tea aroma molecules are formed mainly from four precursor groups: carotenoids, fatty acids, glycosides, and amino acid; sugars.
Ca, Na, K, Mg, and Mn are found in brewed teas in small amount. Other minerals are found in trace amount.