4 Reasons Why Black Tea Tastes Bitter And What To Avoid

Have you ever had a cup of black tea that tastes bitter? This morning a friend of mine was brewing a Jun Jun Mei I recently got her as a sample. She prefers to brew her tea in a larger kettle, which at first resulted in a delightful and sweet first cup of black tea. The second cup taken from the same kettle was undrinkable and bitter.

Instead of creating a thick and sweet tea, your black tea tastes bitter. This is not uncommon! Many black teas contain high amounts of bitter compounds. If you use too much black tea, very high temperatures and brew for too long, your black tea will taste bitter and often be undrinkable.

SHORT ANSWER – Why Black Tea Gets Bitter

Every tea that gets bitter contains higher amounts of bitter compounds. There are a few production steps that reduce or destroy the bitter taste, but you can influence the bitterness of your tea, too!

The 4 main reasons for bitterness with black tea are:

1. Bitter compounds contained in your black tea
2. High brewing temperatures
3. You use too much black tea
4. Your steeping time is too long

Keep reading for a more in-depth explanation of bitterness in black tea. Below you will find the ideal tea making process for black tea that can get bitter, so you can enjoy a perfect cup of black tea.

1. Black Tea Contains Bitter Compounds

There are different compounds that cause bitterness in tea. The primary bitter compounds in tea are caffeine and theobromine. Both of these are also natural stimulants. Camellia Sinensis protects itself against insects with natural bitter compounds.

Polyphenols and tannins are the next most significant bitter compounds found in tea. While technically being considered good for you, molecules of these categories tend to taste unpleasant in larger concentrations. These are the same molecules that give red wine its bitter-dry taste.

The protection these compounds provide is mostly necessary during the summer and autumn. This means that summer and autumn harvested tea is generally more bitter than spring harvested tea. In spring there are far fewer insects that attack the tea plants and the harvested bus and leaves tend to be sweeter.

2. You Brew At High Temperatures

Bitter compounds are not as easily dissolved in water as sweeter contents of tea. Your black tea will taste harsher and can become bitter when brewing with boiling water. Brewing with boiling water is often recommended because black tea could otherwise taste too mild and boring.

Some black teas taste a lot better when brewed with boiling water at very short steeping times whole others taste good with long infusions and lower temperatures or even as a cold brew. For the perfect taste, you will need to experiment with your tea.

Generally speaking, you should expect a tea that tends to become bitter to require lower water temperature. Black tea that gets bitter will taste better with 160 °F / 70 °C water rather than boiling water.

3. You Use Too Much Tea

The compounds in your black tea that create the bitter taste are a minor part of the tea itself. The problem with bitterness is that it is overwhelming with far lower concentrations than sweetness or other tastes are.

If you use huge amounts of tea leaves you will logically also have larger amounts of these compounds in your tea. For you to reduce the bitter taste, you need to use less tea leaves. Using too few, you will lose intensity and nuances, but the tea won’t taste bitter.

The perfect amount of tea hugely depends on the brewing method you use. With a gaiwan, I commonly use 1 gram per 1 oz or 3 grams per 100 mL. For larger brewing vessels I would use about the same amount of tea, but adjust the steeping time.

4. You Are Brewing Too Long

Bitter compounds tend to give a fuller and desirable taste in lower concentrations. In larger quantities, the bitter compounds of your black tea will dominate the taste. As with most teas, the bitter compounds of black tea are harder to dissolve than other desired contents.

If you brew your black tea for more than about 5-7 minutes, you will start to notice the bitter notes in the tea. The longer you brew, the more intense the bitterness will get. 

With shorter brewing times you will achieve a tea that is sweet and full. The bitter compounds will not have time to fully dissolve in the water. If you want your black tea to be welcoming in taste and mouthfeel you will need to adjust this brewing parameter accordingly.

Not All Black Teas Taste Bitter

Most brewing recommendations for black tea allow for boiling water and quite long steeping times. This shows that these black teas are not delicate. They can take a lot before getting bitter or otherwise unpleasant in taste. 

Black tea is a category that is most commonly defined as fully or heavily oxidized tea. This does not rule in or out roasting or other methods used in tea production. Neither does this give information on the material used, be it 3 leaves and a bud or all buds. 

Because of this, you can not determine if your tea could get bitter or not just by knowing that it is black tea. You need to consider the type of black tea and ideally the production methods necessary to produce the tea.

Black Teas That Do Not Get Bitter

There are two major factors that influence the amount of bitter compounds in black tea. Your brewing methods and parameters have a huge impact on the outcome of your tea. Two main factors determine the bitterness of the black tea.

1. Harvesting Season

Firstly, black tea that is harvested and produced in spring or ideally early spring will not taste bitter, but rather sweet and savory.

As described earlier the reason for this is that the tea plant does not need as much protection from insects, as insects are more active during the summer and autumn months. Further, the plant’s leaves will contain more nutrients as they are the first shoots after the winter months.

2. Production Method

The second factor for the bitterness of teas and especially oxidized and black teas is the production methods used. Some black teas will further get pan-fried or roasted, which results in a more robust, less delicate tea.

Through the heating process, bitter compounds can be decomposed. Additionally, roasting flavors will be created, which tend to taste and smell sweet and pleasant.

Think of roasted vegetables or other plant material which in the same way will turn to taste sweet and full. With this process, black tea rarely tastes bitter.

There’s a lot more to learn about tea! If you are looking for a good place to start, I highly recommend the book Tea: History, Terroirs, Varieties. You can check its current price on Amazon here.