TEA JOURNEY [3] | What is the chemical make-up of tea?

Ever wondered how tea leaves + water become tea?

Through the interaction between water and heat, soluble compounds in tea leaves transform into an aqueous phase. Depending on the contact time and water temperature, most soluble compounds dissolve completely with water.

1. Polyphenols

Polyphenols, also known as tannins, are compounds similar to those found in wine, coffee, and leafy vegetables. They're the bitter, astringent flavors that dry your tongue. They make up about 30% of the tea leaves. 

2. Carbohydrates

Although carbohydrates are abundant in tea leaves, only a small amount of one type dissolves. Some teas have a subtle sweetness, which comes from simple sugars. About 25% of the tea leaves.

3. Amino Acids

Tea contains around 20 different amino acids. The most important one is Theanine, a unique amino acid found only in tea and camellia plants. Theanine makes up 60% of the amino acids in tea leaves. Amino acids make up about 15% of the tea.

4. Aromatic Compounds

Aromatic compounds contribute to the aroma of tea and are considered the "soul" of the beverage. There are over 600 aromatic compounds found in tea. They decide the aromas of the tea, be it fruity, floral, nutty, or leafy. They are also less than 0.1% of the chemical make-up of the tea.

5. Minerals and Vitamins

Fresh tea leaves are rich in vitamin C, but it gets destroyed during the fixation and drying process at high temperatures in tea production. Tea leaves also contain vitamin B flavonoids, fluoride, potassium, calcium, and magnesium. They make up about 3% of the tea. 

6. Xanthines

Tea leaves naturally contain three nitrogenous molecules: caffeine, theophylline, and theobromine. Among them, caffeine is the most important.

Reference: "Tea is Not Hard" GREENCOOK, pp 55