What are the different types of tea and tea processing methods?

Updated: Nov 2, 2021

An overview of key tea types and steps the tea undergoes before it makes into our daily cuppa.

Female pickers working on a tea plantation plucking loose leaf tea leaves from the camellia sinensis bushes.
Tea plucking on a tea plantation in the foreground and camellia sinensis bushes in the background.

How does tea get transformed from leaves growing in the bushes to this beautiful versatile drink known all over the world? Let’s talk about key manufacturing processes that tea undergoes to turn it into your favourite daily cuppa.

Before we dig in, let’s highlight a few things we are going to cover in this blog post:

  • Tea manufacturing process

  • Different tea types - white, green, black and more

How does tea get manufactured?

Tea manufacturing process is quite simple yet labour intensive. It all starts with the plant. The leaves get picked, sorted and undergo a process of oxidation and/or fermentation (different tea types would go through a slightly different process which impacts the end outcome and flavour). So it is really important to remember that whether a tea is green or black is determined by the processing, not by the type of tea plant. This is a common misconception about how tea grows. A lot of people think that green tea comes from a different plant in comparison to black or white. In reality, it’s just how it’s being processed.

Broadly speaking there are 7 key tea types - black, green, white, fermented pu-erh, oolong, infused/scented teas that come from the camellia sinensis tree, other drinks such as peppermint or camomile are technically not considered ‘tea’ given they don’t grow on the Camellia sinensis. They can be called ‘tisanes’ or ‘infusions’. We will cover that later.

But let’s get back to the processing methods. Firstly, there are between two and seven procedures involved in the processing of fresh tea leaves. And it is the addition or exclusion of any of these stages that result in a different type of tea. Each of these procedures is carried out in a climate-controlled facility to avoid any damage/spoilt leaves due to excess moisture, too much oxygen or just unstable temperatures.

Step 1: Tea withering

Technically, this is the first step, but it’s worth mentioning that it all starts with tea plucking that usually occurs very early in the morning. The plucking of the soft two leaves and the bud is generally undertaken by well trained women. The manufacture begins from the time the leaf is plucked in the field, and to ensure it retains its freshness, the leaf is sent to the factories as soon as possible.

When received at the factory once weight it undergoes a process of withering, where conditioned air is circulated between the leaves, initially to remove any surface moisture and thereafter to concentrate and chemically breakdown the tea juices. It takes 10 hours to 14 hours for the physical and chemical changes to take place, and bring the leaf to soft and rubbery condition suitable for the next stage of manufacture. During the course of withering, the moisture content in the leaf goes down by about 30%, making the leaf look limp and soft enough for rolling. Additionally, the volatile compounds in the leaf, including the level of caffeine and the flavours, begin to intensify. A short wither allows the leaves to retain a greenish appearance and grassy flavours while a longer wither darkens the leaf and intensifies the aromatic compounds.

Step 2: Tea fixing

Fixing is a process of applying heat to brown wilted tea leaves. It is held that the longer it takes to fix the leaves, the more aromatic will the tea be. There are different techniques (some more popular in particular regions than others) - it could be steaming, pan-firing, baking or with the use of heated tumblers. Application of steam heats the leaves quicker than for instance, pan firing. This has a big impact on the overall result and tea flavour - steamed teas tend to taste more ‘green’, vegetal and grassy, whereas the pan-fired ones taste toasty or even roasted. This procedure is carried out for green teas and yellow teas only.

Step 3: Tea oxidisation

If we want the tea to have stronger flavour we need to take it through a process of oxidation - it results in the browning of the leaves and intensification of their flavour compounds. From the moment they are plucked, the cells within the tea leaves are exposed to oxygen and the volatile compounds within them begin to undergo chemical reactions (which also means losing flavour). Interestingly, it is at this particular stage that compounds such as theaflavin and thearubigin, begin to develop within the leaves. Theaflavins lend briskness and brightness to the tea while thearubigins offer depth and fullness to the liquid that’s produced. In order to bring out specific intensities in flavours or tea characteristics, tea makers control the amount of oxidation the leaves undergo.

Withered and rolled leaves are spread out on long shelves and left to ferment for a fixed period of time, depending on the type of tea being made. To halt or slow down oxidation, fermented leaves are moved to a panning trough where they are heated and then dried.

Due to oxidation, the leaves undergo a complete transformation and exhibit an aroma and taste profile that’s completely different from the profile of the leaves that do not undergo this process. Less oxidised teas tend to retain most of their green colour and vegetal characteristics due to a lower production of polyphenols. A semi-oxidised leaf has a brown appearance and produces yellow-amber liquor. In a fully oxidised tea, amino acids and lipids break down completely, turning the leaves blackish-brown. The flavours in such a tea are more brisk and imposing. As fermentation progresses there is a colour change of the leaf from greenish to coppery brown. The degree of fermentation is judged by the colour and aroma. It’s quite amazing how this particular step transform and defines the tea flavour.

Step 4: Tea rolling

Rolling basically involves shaping the processed leaves into a tight form. As a part of this step, wilted/fixed leaves are gently rolled, and depending on the style, they are shaped to look wiry, kneaded, or as tightly rolled pellets. During the rolling action, there might be essential oils being applied to the leaves (such as jasmine or bergamot) to intensifying the taste further. The more tightly rolled the leaves, the longer they will retain their freshness (less exposure to oxygen).

Step 5: Tea drying

Tea doesn’t like moisture or oxygen. In order to keep the tea moisture-free, they are dried at various stages of production. Drying enhances a tea’s flavours and ensures its long shelf-life. Also, drying brings down the tea’s moisture content to less than 1%. To dry the leaves they are fired or roasted at a low temperature for a controlled period of time, typically inside an industrial scale oven. If the leaves are dried too quickly, the tea can turn abrasive and taste harsh. It requires a lot of practice to get this technique right.

Step 6: Tea ageing (optional)

Some tea types undergo a further process of ageing which adds a lot of flavour the specific tea types (i.e. pu-erh). You might have seen famous ‘tea cakes’ that you need to handle with a little knife - they are very aromatic and strong - something brilliant for the connoisseurs!

Step 7: Tea grading

Once the tea has gone through all the steps above it needs to be graded and sorted. It’s a process of evaluating the leaves and their quality. On completion of the grading, teas are stored in airtight bins of boxes. The sifting is carried out on a series of grading and cleaning machines, which have several trays of different mesh sizes, to separate the tea particles to the various grades of tea and to remove the stalk and fibre. After that the tea is packaged and send to the buyers/markets.

Ok, enough about the process, but what are all the different tea types then?

What are the different types of tea?

Like we said earlier, all tea comes from the same plant called camellia sinensis (except for herbal infusions that aren't technically considered ‘tea’) – it is how it's grown, harvested and crafted that produces the different types.

  1. White tea - the most delicate tea type (don’t confuse it with black tea with a splash of milk!) that has the most antioxidants. It’s also the least processed (dried only) and has a very light and delicate flavour. Silver needle or Bai Mu Dan (White peony) are one of the most popular varieties.

  2. Green tea - soon after picking the leaves are steamed or fired to avoid too much oxidation happening that would lead to leaves turning brown. There are many different types and depending on your flavour preference you can go for something heavier with more flavour like sencha or milder such as LongJing.

  3. Oolong - it’s a bridge between black and green tea. It’s stronger and has more body in comparison to green but is lighter than black. The tea is partly oxidised and the greener leaves are more delicate (taiwanese green oolong), whereas the brown ones are more nutty, woody and earthy (wuyi oolong).

  4. Black tea - it’s strong and has the highest level of caffeine in all teas. It’s fully oxidised hence the dark colour. There are many varieties to enjoy - for a lighter flavour pick Darjlelling, and if you want something really bold go for Assam. A good in-between option would be a famous English Breakfast.

  5. Flavoured/Infused tea - Tea leaves can be scented with oils, such as bergamot, citrusy or jasmine (famous jasmine green tea). They should be natural, however many brands use artificial flavourings so double check the labels to ensure you are getting what you want. French Earl Grey is a great example of a black tea scented with bergamot oil.

  6. Pu-erh - fermented tea with a very strong aromatic flavour. Often comes in special ‘tea cakes’ and has a very characteristic, woody and often earthy flavour. Might be a little intense at the beginning, hence many consider this an acquired taste.

  7. Herbal ‘tea’ - dried herbs such as chamomile, peppermint, rose. They technically aren’t considered tea because they aren’t derived from the tea plant (camellia sinensis) and have no caffeine. They are a fantastic and aromatic drink if you are looking for caffeine free alternative with health benefits (i.e. chamomile helps with sleep and relaxation, peppermint helps with digestion etc.)

Overall, tea flavours can range from heavy and bold blacks (i.e. assam or earl grey) to grassy or floral green (i.e. sencha or lingjing) or sweet and subtle white tea. Tea’s provenance (i.e. what region it exactly it came from) also plays a large role in the tea flavour - sencha from Australia will taste a little different to a japanese Sencha.

It’s also worth adding, that tea can be drunk either hot or cold, depending on brewing properties and your preference.

Key take aways

  • Tea manufacturing is quite a bit of a process and involves several steps starting with plucking followed by withering, frying, rolling, oxidising, drying and grading. Some teas can also be aged.

  • There are 7 different tea types, however, only some of them are considered ‘tea’ given their provenance (they have to come from a camellia sinensis plant). The ‘actual’ teas include white, green, black tea, oolong, pu-erh and infused /scented teas. Herbals ‘teas’ are called tisanes as they come from different bushes, not a camellia sinensis one.

What's your favourite type of tea? Do you like it by itself or do you prefer it blended? Leave a comment here of jump to our forum where you can chat more about it with other like-minded tea enthusiasts!