Preparation & barista workflow
Why Is My Matcha Latte Bitter? A Troubleshooting Guide
A bitter matcha latte usually has one of four causes: water that is too hot, too much matcha for the cup, a paste that has stood too long, or powder that is past its best. Check water temperature first, then dose, then timing, and only then the matcha itself; that order finds the problem fastest. Some bitterness is part of matcha's character, so the goal is balance, not none at all.
Bitterness or astringency?
Before troubleshooting, be clear on what you taste. Bitterness is a taste on the tongue, often lingering at the back. Astringency is a drying, grippy feeling on the gums and cheeks. Both come from the tea, both rise with hotter water, but astringency is also more noticeable when there is less milk to soften it. Ask staff to describe what they notice; it narrows the diagnosis.
Diagnosis table: symptom → likely cause → fix
| Symptom | Likely cause | Fix |
|---|---|---|
| Sharp, harsh bitterness on every drink | Paste water too hot (straight from the hot tap) | Bring paste water to around 80 °C; check with a thermometer |
| Bitter and very intense, dark green colour | Dose too high for the cup | Weigh the dose; check grams against cup size |
| Bitter only in small cups | Same dose used for all sizes | Set a dose per cup size on the recipe card |
| Bitterness varies between baristas | Scooping by eye; different water sources | Weigh every dose; use one water method for everyone |
| Bitter, drying finish in plant-milk lattes | Milk flavour or low fat lets bitterness through | Test another barista milk, or adjust dose and milk volume |
| Bitter and flat, with dull colour | Paste made in advance and left standing | Make the paste per drink; combine straight away |
| Bitter and stale, slightly hay-like, across all drinks | Powder degraded by heat, air or long open storage | Check stock against the signs of degradation; open fresh stock |
| Bitter in a pure (water-only) serve but fine in lattes | No milk to soften it; matcha choice | Check temperature and dose; consider a matcha made for pure preparation |
| Bitter after switching suppliers | Different matcha, same recipe | Re-test dose and temperature for the new powder |
Check order on the bar
Work through these in order. Change one variable at a time and taste again.
- Water temperature. Probe the paste water in the jug. Producer guidance such as Ippodo's usucha method uses 80 °C; most espresso hot-water taps run well above that. See water temperature for matcha.
- Dose. Weigh the matcha. A scoop by eye can vary considerably. Compare your grams to cup size using the grams per latte guide.
- Milk ratio. Measure the milk. Less milk than intended makes the same dose taste stronger and more bitter.
- Timing. Is the paste made per drink, or batched and left to stand? A paste that waits tends to lose freshness of flavour.
- The powder. If all of the above are right and every drink still tastes bitter and stale, look at the stock.
When the problem is the matcha itself
Matcha that has been stored warm, left open, or kept for a long time after opening loses its fresh, rounded character and can taste flat and bitter. Look for other signs at the same time: a duller, yellowish or olive colour, and a weaker or hay-like aroma. The guide on signs your matcha stock has degraded explains what to check and what to do.
If your stock looks and smells fine, the matcha may simply not suit the drink. For milk drinks, use a matcha made for milk, such as Ceremonial Barista Matcha. For water-only serves, where nothing softens bitterness, Ceremonial Matcha for pure preparation is the product made for that use.
A quick side-by-side test
When you are not sure which variable is the cause, run this on your own bar:
- Make two lattes with the same dose and milk.
- Use around 80 °C water for one and hot-tap water for the other.
- Taste side by side.
- If both are bitter, repeat at a lower dose.
- If both are still bitter, repeat with a freshly opened bag or sample.
Write down what changed the result, then update your recipe card.
Prevent it from coming back
- [ ] Paste water temperature checked at the start of each shift
- [ ] Dose weighed, not scooped by eye
- [ ] One dose per cup size, written on the recipe card
- [ ] Paste made per drink
- [ ] Working tin closed, away from the machine and steam
- [ ] Stock rotated: oldest opened first
Next step
If you suspect the powder, compare your current matcha with both 10 g samples using the side-by-side test above, then choose the 1 kg bag that matches your drinks.