Science of chai

In just one cup of chai, there are thousands of chemical compounds.

Remember Chemistry 101? Chemical formulas. Chemical equations. Well we sure had to dust off our old text books and remember it all. Authentic chai has thousands of compounds and we wanted to really understand what happens when a cup of chai is brewed, so that we could apply that knowledge in designing Chime. After all, what really matters is that Chime produces the most delicious cup of chai customized to your preferences.

Compounds found in black tea

Many compounds are found in black tea to give it the unique taste. We started by understanding the role each compound plays in creating the commonly loved aroma and taste of chai:

  1. Polyphenols. Polyphenols are organic chemicals that prevent degenerative diseases (including cancer). A form of Polyphenols, Flavonoids are responsible for providing antioxidant properties, which we know, prevent aging. Flavonoids also support cardiovascular health and a better stress management. Flavanols (tannins) are most prevalent and during oxidation are converted to theaflavins and thearubigins — compounds responsible for color and flavor in black tea.
  2. Amino Acids. Amino Acids are the building blocks of proteins. In chai, Amino Acids play the role of providing the umami taste, or brothiness. You will find the Amino Acid, L-theanine in black tea. It catalyzes alpha brain waves that promote relaxation. L-theanine combined with caffeine creates a state of “mindful alertness”. Thank you L-Theanine.
  3. Enzymes. Enzymes are catalysts of biochemical reactions and are responsible for browning of the tea leaves during the drying process, oxidation, which makes the tea black.
  4. Pigments: Pigments are found naturally in tea. The natural color of tea comes from the pigments of chlorophylls and carotenoids. Pigments are released from chlorophylls and carotenoids during the oxidation process. The process of oxidation not only impacts the color of the tea but also taste and aroma compounds, strength, and briskness.
  5. Carbohydrates: There are carbs in my chai? Yea, well, carbohydrates are necessary to fuel the enzymatic reactions during oxidation. As mentioned above, oxidation is an important step in the creation of black tea.
  6. Alkaloids. Alkaloids are mostly basic nitrogen compounds that show up early in the life of tea and stick around in the final tea leaves. They are created as an natural insect repellant . Alkaloids also include caffeine and related compounds. They impart bitter taste in tea infusion. We are glad they naturally occur and stick around!
  7. Minerals. 28 minerals are found when tea is harvested and this changes during processing, hence lots of great minerals are found in our cup of chai.
  8. Volatiles. Volatiles are compounds that evaporate during processing and are responsible for the flavor and aroma of tea. The aroma and flavor of tea can easily be altered by the thousands of compound combinations that are possible.

Chemical Reactions: Denaturing and Tanning

Two chemical reactions take place when you make a cup of chai that alter the protein of the milk: denaturing and tanning. It was necessary for us to understand these reactions as we explored how the simmering milk would react with the brewed tea and spices.

We looked at the practices of “milk-first” and “milk-last”. The Brits had a lot to say about that. This is a traditional tea practice in Britain. After brewing a pot of tea, either you add milk to the tea (milk-last) or add tea to the milk (milk-first).

In denaturing, bio chemical changes take place in milk when it is heated. This change depends only on temperature. So — simmering the milk first and then adding the brewed tea was the way to to ensure the boiled milk flavor. We made sure we designed Chime to capture this.

In tanning, analogous to the tanning of leather, the protein of untanned hide is combined with tannin to form chemically tough collagen/tannin complexes, so in the teacup, the milk’s protein turns into tannin/casein complexes.

However, different from the tanning process of leather where every reactive point on the protein molecule is taken up by a tannin molecule, this doesn’t happen when mixing tea with milk. Unless the brew is strong enough to tan all the casein completely. This is desirable in authentic Chai.

By the way, ‘milk-first’ will react differently from ‘milk-last’ in the way it distributes the tannin through the casein. In ‘milk-first’, all the casein tans uniformly; in ‘milk-last’ the first molecules of casein entering the cup tan more thoroughly than the last ones. If the proportions of tannin to casein are near to chemical equality, ‘which-first’ may determine whether some of the casein escapes tanning entirely. Therefore, again these processes lead to different tastes.

Keeping in mind each compound and the impacts of chemical reactions, we have designed Chime purposefully to capture the properties, flavor, aroma and benefits a traditional hand-made cup of chai offers.

We can’t wait until you have Chime in your kitchen. You can then, hit a button, close your eyes and imagine all the compounds and work and watch the reactions taking place in front of your eyes.

Until next time!

Sources:

The USDA Tea Research

Teamuse — The Chemistry of Tea

George Orwell — A Nice Cup Of Tea