What is Tea and How to Make Iced Tea

This tea and how to make iced Tea post explores different ways of making iced tea and examines the various types of tea and some of their differences.

Tea is one of the purest drinks, with no added chemical or artificial ingredients in the final product. It is a very versatile beverage, great for infusions, cocktails, non-alcoholic drinks, etc., and at the same time has lots of health benefits.
When I lived in Georgia, USA, I got used to iced tea, a refreshing and thrust quencher drink. Back then, I worked for one of the Marriott hotels, and we had a lot of banquette business; every time we prepared the table set up next to the glass of water, we had a cold glass of freshly brewed iced tea.
At that time, I never really asked myself if there was any better way of making iced tea, whether it made any difference, whether I used hot or cold water, or if it was all about flavour perception and expectations.

During our family vacation to Thailand, I genuinely appreciated tea and the tea manufacturing process. One of our stops was in the Chiang Rai province, where we stayed in a small resort in the middle of a beautiful tea plantation. I was introduced to a local tea ceremony and tea tasting, and I understood how hard the locals work to make tea so we can enjoy our cup of tea.

At first glance, making a cup of tea seems as simple as it gets; all you need is tea and hot water. In reality, it may not be that simple.
The moment you start asking yourself what tea you should drink, how long to steep it in, whether green tea is better than black, whether you should use boiling water, whether loose-leaf tea is better than the one sold in teabags, etc. You probably already realized there is more to tea than just hot water and tea bags.

What is Tea

All tea is made from the leaves of the Camellia sinensis plant. There are two primary varieties: Camellia Sinensis, Chinese tea, and Camellia sinensis, assamica, Assam, or Indian tea. This plant, or tree, can grow up to 5 meters.

Tea is full of health-boosting antioxidants. According to some researchers, the ingredients in a cup of tea can also improve focus and mood and even help fight depression and dementia.
As the tea comes from the leaves of the same plant, the processing steps and the oxidation determine their flavour and chemical composition differences.
The main difference between tea types is based mainly on oxidation levels.

Types of Tea

These are the main types of tea:

Pu-erh or Puer

Pu-erh is one of the most well-known post-fermented teas. It originated thousands of years ago in the Yunnan Province of China, and it is named for the town from which it was initially sold en route to other countries (Pu’er City).
Pu-erh is an aged tea; the aging process can take about 15 years for a ‘raw’ (unfermented) pu-erh to get the dark colour and flavour. In the 1970s, shou processing (or ‘cooking’) was developed to speed up fermentation. Nowadays, it takes about 45-60 days to complete the fermentation.

Note:* Black teas, for instance, are fully oxidized. The leaves are first allowed to wither, then ‘rolled,’ which involves rubbing or crushing the leaves to release the chemicals that begin oxidation. The leaves are then oxidized in a temperature—and humidity-controlled room, turning completely brown before drying. Because of this process, black tea has fewer green catechin polyphenols than other teas.
Note:** For more on Japanese green tea, click here.

Science Fun Time

The chemical composition is different in each type of tea. The reason for that is the chemical changes during the processing of the fresh leaves, mainly caused by oxidation.
Fermentation is often used to describe making tea, but it is essentially an oxidation process; the polyphenols are exposed to oxygen and oxidase enzymes, which convert the polyphenols into theaflavins and thearubigins.

The polyphenols in the tea leaves are stable as long as the leaves remain on the live plant. The oxidation process starts naturally when the leaves are picked (like an apple beginning to go brown once cut).
The tea and its chemical compositions can change depending on the variations in processing conditions and techniques.
Applying heat during processing stops the oxidation process and enzyme activity. By controlling the degree of oxidation, the tea maker creates tea’s distinctive flavour and chemical profile.

Note: Green, white and yellow teas are subject to very little oxidation because they are heated soon after picking.
The polyphenol content of these teas is very similar to that of the fresh leaves, and the brewed tea has a mild flavour.
In contrast, for black tea, the leaves are cut and bruised. This disrupts the cell structure and allows all the leaf juices (containing polyphenols) and enzymes to mix, allowing complete oxidation.

After the leaves have been picked and the Oxidation process is done, the cell walls are mechanically broken after wilting (or withering). This process mixes catechins and enzymes, resulting in the enzymatic browning of the leaves and new taste and aroma profiles.

One of the main compounds in tea leaves is polyphenols, which can be up to 40% of the dry weight of the leaf; besides them, there are also amino acids, enzymes, methylxanthines – caffeine minerals and vitamins, as well as around 700 aroma compounds.
Polyphenols, also known as tannins, are responsible for the astringency of taste and some colours and are believed to have strong antioxidant properties.
The most important group of polyphenols in tea is flavonoids. During processing, two new phenolic compounds—theaflavins and thearubigins — are formed from flavonoids responsible for the tea’s colour and flavour.

Tea catechins — antioxidants such as epigallocatechin gallate (EGCG) — account for up to 42% of the dry weight of brewed green tea, and the amino acid L -theanine makes up around 3%. EGCG makes people feel calmer and improves memory and attention when consumed independently. L – theanine is found to have a similar effect when consumed with caffeine.

One thing I found interesting from a scientific point of view is that even these days, researchers still don’t understand how tea’s compounds work together.
For instance, caffeine, according to an article in Nature Boost¹, still has a lot to learn about its interaction with other compounds.
“Caffeine is known to benefit mood and cognition, and its biochemistry is widely understood — it stops the sleep-controlling chemical adenosine from binding to its receptors, helping to maintain neural activity and making caffeine drinkers feel more awake. However, little is known about how caffeine interacts with EGCG. Similarly, it is unclear whether caffeine boosts the cognitive effects of L-theanine or vice versa.”

Making tea

The timing and frequency of harvesting fresh tea leaves depend on environmental conditions and ultimately impact tea flavour, quality, and type.
Tea harvesting is an arduous process done by hand and with special pruning shears. The main goal is to pick the right buds and avoid bruising the leaves. Experienced pickers collect leaves only from the top of the tea plant, where there are usually only 1-3 leaves.
The tea harvesting season is anywhere from eight months in Southern Asia to four months in Northern China.

Two main ways of producing tea

According to A. K Barooah, director of the Tocklai Tea Research Association in India, has two maceration techniques – Orthodox and CTC- that produce different chemical constituents. As he explains, “Orthodox tea is more flavoured and less coloured, while CTC tea produces a very strong coloured liquor with a mild flavour.” as a result, orthodox teas are usually considered higher quality and, therefore, more expensive than CTC teas.

Orthodox teas

They are usually harvested and processed by hand, focusing on whole leaves, and trained professionals determine every stage. These teas(white, green, oolong, or black) are known for their flavour complexity and are highly prized in the world tea market.

There are different grade systems for Orthodox teas; probably the most common one uses letters. That grading system is typically used to grade black tea, mainly by exporters targeting Western countries. As far as I know, China does not use this grade system.

There are four major categories, and these are some of their grades.

Whole-leaf teas need longer infusion times, whereas broken-leaf teas require shorter steeping, and fannings and dust infuse the fastest. Whole-leaf teas are also best for multiple infusions.

CTC teas

CTC stands for crush, tear, and curl. The tea leaves are passed through a machine with sharp teeth, which essentially minces the leaf.
There are different grades of CTC teas, and here are some of them.

CTC teas are the base for famous blends, like English Breakfast or Spicy teas—masala/chai, cardamom, ginger, etc.

Apart from the production process, Orthodox and CTC teas differ mainly in flavour, price, and use. Orthodox tea is more expensive and has a more delicate flavour, and its appearance is not as small as that of CTC teas, which look like tiny pellets.
Is one better than the other one? I am unsure; it is a matter of personal preference at the end of the day.

Tea quality can also be affected by the environment, the time of harvesting, which leaves are used, and farming practices, but not to the same extent as the production process.

Steps in Tea Manufacturing

How to make a cup of tea

The answer is easy– boil water, put the tea in it, and wait. Or maybe not.
Does it matter how we make tea? Is the amount of tea used, the water temperature, and the length of the steeping process essential to the tea’s flavour?

How much tea?

Usually, the amount of tea used is 2g per 100 ml for tea testing and 1g per 100 ml for everyday use, steeped for about 5-6 minutes.
According to Leo Kwan in his article Better Tea-making: Measurements, “Good measurement practice is key to successful tea-making.” The usual capacity of a teacup is 250ml, but since we are filling in only 2/3 of it, the liquid used for a cup of tea is no longer 250ml but more like 150ml—175ml. If we base our assumptions on that, we can adjust the amount of tea needed.
So, how do we measure 1g or 3g of tea leaves? They all have different densities; a teaspoon full of one type of tea doesn’t necessarily mean the same amount of a different kind of tea.
The short answer is that you need a small-weight scale. If you don’t have one, check the link to this article for more detailed information about tea measurement.

Water temperature

Water temperature plays a vital role in extracting the tea’s chemical compounds and flavour. The temperatures are based on the assumption the teapot is pre-warmed and served at room temperature.

Example of suggested water temperatures

Iced Tea

When making iced tea, we usually use hot water and tea, let it infuse, strain it, and put it in the fridge. The question is: Is it better to infuse the tea with hot water or cold water when making an iced tea? The answer is not straightforward, and it depends on personal preferences. After all, comparing taste and aromas can not be objectively categorized. Nevertheless, here are some factors to consider.

Let’s say we pour hot tea over ice; the resulting drink will have a more pungent astringency taste and release additional bitterness into the tea.
Does that mean we should not use hot water to make iced tea? Of course not. Here are some suggestions for making iced tea using the hot and cold brew methods.

Hot Brew method

When brewing with hot water, use more robustly flavoured green, oolong, or black teas.
Here are some steps to consider when using the hot brew method:

1. Use two bags of 300ml water or the equivalent in tea leaves
2. Put sugar during the steeping process when the water is hot but not boiling.
3. If you need a more robust flavour, add more tea; don’t extend the infusion time, as it will increase the tea’s astringency.
4. If you need to add more sweetness to the tea afterward, use simple syrup and not granulated sugar, as it might leave sugar grain on the bottom of the glass.
5. Cool the tea before refrigerating; otherwise, it may get cloudy.

Brewing using the cold method:

Usually, cold-brewed tea comes out a little sweeter than its hot counterparts.

Add tea leaves to a container with cold water and let them sit at room temperature for about 30 minutes. Then, put the container in the fridge, wait 6-8 hours, strain, and refrigerate if not needed immediately.
Good quality tea leaves can be used again, but you might have to double the infusion time.

According to Elena Liao, founder of Té Company in New York and importer of Taiwanese oolongs, “The colder temperature doesn’t steep out the tannins in the way hot water does, so cold-brewed tea is less astringent and less caffeinated.” And… the best teas to use are a little bit sweeter, like a light oolong.

Ice Brew Methods

They are known as kouridashi-style brewing, an ice-cold method of extracting tea flavour from Japan.

Again, the key is to increase the number of tea leaves compared to the hot brew.

Here are four different methods of using this technique.

Note: A kyusu is a traditional Japanese teapot made of clay

• The Kouridashi method is a truly unique presentation. It might take 2-3 hours to have the tea ready. It works by placing large ice cube(s) in a pot or large enough glass – if Kyusu pot is not available, and waiting for the ice to melt. The slow-melting ice concentrates the flavour of the tea without pulling out the astringency, which most caffeinated drinks have. This slow infusion process allows additional flavours to be added (ginger, citrus peels, lemongrass. berries, or whatever flavour is desired). This infusion idea is similar to the one used in the Porthole drinks, minus the ice. – https://www.theportholeinfuser.com/
• If this method seems too long to wait for a cup of tea, add some water to speed up the melting process.

There are so many great teas out there that it is virtually impossible to mention in this post, but this particular tea is one of my favourites and has an exciting story.

1. https://www.canadianliving.com/food/food-tips/article/six-rules-for-the-best-iced-tea-plus-recipes