First, Know What You're Actually Tasting
Most people use "bitter" for two genuinely different sensations, and knowing which one you're getting helps narrow down the cause.
Astringency
A dry, puckering sensation felt on the sides and edges of the tongue — similar to red wine or dark chocolate. This is often a desirable part of tea's character, not a flaw.
Bitterness
A sharper, more unpleasant taste felt toward the back and middle of the tongue. This is the sensation people usually mean when they say their tea "went wrong."
The Most Likely Culprits
Over-Extraction
Steeping too long or using water that's too hot pulls out more tannins than the tea can balance. Our full brewing guide covers the correct time and temperature for every tea type.
Squeezing the Tea Bag
It's a small habit with a real effect — squeezing forces out extra tannin-rich liquid that was still trapped in the leaves, tipping a balanced cup into a bitter one.
Low-Grade Leaves or Tea Dust
Broken leaves and fine tea dust (common in cheaper tea bags) have far more surface area exposed to water, so they release tannins faster and more intensely than whole or large-leaf tea.
It Might Be Your Water, Not Your Tea
Hard water — water naturally high in calcium and magnesium — reacts differently with tea compounds than soft water does, and tends to bring out a harsher, flatter bitterness rather than the pleasant astringency you'd get otherwise. This is part of why tea grown in regions with naturally soft water, like much of Japan, has adapted over centuries to suit it. If you live in a hard water area of the UK and your tea consistently tastes off even with careful brewing, filtered or bottled water is worth testing before blaming the tea itself.
Sometimes, It's Not the Tea — It's You
Bitter taste perception has a genuine genetic component. Researchers use sensitivity to a compound called PROP (propylthiouracil) as a marker for how strongly someone perceives bitterness generally, including in tea. People with this heightened sensitivity are sometimes called "supertasters."
of people are estimated to be highly sensitive "supertasters" — if you're one of them, tea that others find perfectly balanced may genuinely taste more bitter to you.
This is documented in peer-reviewed research on the genetics of bitter taste perception, which found that genetically predicted bitterness sensitivity is causally linked to how much tea and coffee people choose to drink.
Why Milk Actually Fixes a Bitter Cup
If your tea has already gone bitter, milk is the most reliable rescue. Proteins in milk bind to tannins, softening their harsh edge and restoring balance almost instantly — this is genuine chemistry, not just a matter of taste preference. It's a useful fix for the cup in front of you, though brewing it right the first time is still the better long-term habit.
Quick Diagnostic Checklist
Did you steep it longer than recommended for that tea type?
Was the water too hot for a delicate tea like green or white?
Did you squeeze the tea bag before removing it?
Do you live in a hard water area?
Is the tea a cheaper, dust-grade blend rather than whole leaf?
Switch to Whole Leaf, Skip the Dust
Since leaf grade is one of the causes above, here are two ways to move away from bitter tea-bag dust entirely.
Complete Kit
Loose Leaf Tea Starter Set
Teapot with infuser, a precise 2g measuring spoon, and 100g of whole-leaf tea — no more guessing, no more dust.
3 x 100g
Exotic Loose Leaf Tea Bundle
Spiced Apple Chai, Tropical Rooibos, and Jasmine & Mint Green Tea — finest whole leaf, no artificial flavouring.
Read the Full Guide
Tea vs Coffee: Caffeine Content, Health Benefits & Which to Choose →
Related Reading
How to Brew Loose Leaf Tea Properly →
Shop Our Loose Leaf Tea Range
Whole-leaf teas naturally release fewer harsh tannins than dust-grade bags.
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