Matcha Tastes Like Grass or Bitter: A Cafe Fix List

By Christian Mauerer, founder of One with Tea. Published October 8, 2026.

When matcha tastes bitter at your bar, check the water first. Bitterness is linked to caffeine, and bitter and astringent taste to tea polyphenols such as catechins. In the studies below, hotter water dissolved more phenolics from matcha and raised bitterness scores in leaf tea. When it tastes like grass, the leaf's green notes are coming through, and my first suspects are the age of the powder, the dose and the grade. Work through six checks in order: water, dose, sifting, age, batch, then grade. The first five need only a scale, a thermometer and a strainer.

If you are comparing, here is caffeine and L-theanine across every tea type.

This guide is for cafe and boba operators, not home brewers. Making one cup at home? Our matcha troubleshooting guide covers the home fixes. I'm Christian, and I plan every drink at 3 g of matcha, so the numbers below use that dose. The order of checks is my own diagnostic starting point, not a lab result. Where a paper backs a step, I link it.

Key Takeaways

Check the water first: pull the matcha base at 150 to 160°F (65 to 71°C), never boiling. Hotter water raised bitterness scores in one leaf-tea panel and dissolved more phenolics in one matcha study, but the one matcha panel, which scored liking, rated plain matcha's taste about the same at all three temperatures.
Weigh 3 g per shot and sift every dose. Date every opened bag, and stir any batch before each pour.
Milk softened astringency in an abstract-only lab test on chilled catechin solutions, not matcha, so test every fix in the milk you pour.
If five checks pass and the cup is still harsh or flat, compare grades blind. No study I found tested grade for taste in matcha.

A man in a mustard-yellow jacket holding up a single tea shoot beside a field of bright new tea growth, with a dark forest behind, on a farm in Shizuoka — Looking closely at one shoot on a farm in Shizuoka. The grassy note starts in the leaf.

Why does matcha taste like grass or bitter?

Caffeine and polyphenols such as catechins are among the compounds linked to bitter matcha, and in the Ali et al. study below hotter water dissolved more phenolics from matcha. It tastes like grass when the leaf's green notes outweigh the sweet, savory ones, and some grassiness is normal in whole shade-grown leaf. Name the one you have before you change anything.

The fix list: what the cup says, what to check, what to change
The cup says	Check first	Fix
Bitter, dry, harsh	Water temperature	Pull the matcha base at 150 to 160°F (65 to 71°C). Never boiling. Iced: cool water.
Thin, mostly milk	Dose against the cup size	Weigh 3 g on a scale and size in whole shots. A double is 6 g in 90 ml.
Gritty, or uneven from cup to cup	Sifting	Sift every dose.
Dull, flat or brownish	Age and storage of the powder	Date every opened bag, oldest first, sealed, cool and out of the light.
Grassy or sharp	Age, dose and grade	Check the powder's color and open date, then the dose against the milk, then compare grades blind.
Weaker or different late in the shift	A batch that settled or sat	Stir before every pour, keep it cold, batch for the rush only.
Still harsh or flat after the first five	Grade	Compare the next grade blind, in your own milk, at the same dose and temperature.

What bitter is made of

Bitter is a taste, and astringent is a dry, tightening mouthfeel. A 2023 study of 11 matcha samples from the Chinese market describes tea polyphenols as related to the bitter and astringent taste of tea soup. It calls caffeine highly related to bitterness and free amino acids important to the fresh taste (Luo et al., 2023). Catechins are one group of those polyphenols. Two of them, epigallocatechin gallate (EGCG) and epicatechin gallate (ECG), show relatively strong affinity for TAS2R39, one of the human bitter taste receptors (Jalševac et al., 2022, a review).

What grassy is made of

In one 2020 aroma study of green tea, cis-3-hexen-1-ol was the most influential of 12 green-aroma components, and the paper says the "raw grass" version of that odor, from an over-strong green aroma, is thought to hurt green tea aroma (Nie et al., 2020). That tea was a Chinese green bud tea, not matcha.

A little green note belongs in matcha: our taste guide describes good matcha as savory and smooth, with a gentle sweetness and a fresh, grassy note. It's a fault when the grass is sharp or the cup has nothing else in it. I found no study that tied a grassy cup of matcha to powder age, dose or grade, so my checks for it are a heuristic.

Is your water too hot?

Rows of bright green new tea growth across a field in Shizuoka with a dark cedar forest behind — New growth on a Shizuoka farm. Hotter water pulls more out of the same powder, so the pull is the first thing to check.

Anything above about 160°F (71°C) is hotter than my matcha base, so check it first. I pull the base at 150 to 160°F (65 to 71°C), as in our matcha shot guide, and never use boiling water. Our best temperature for matcha guide warns that water above 185°F (85°C) scorches the powder and turns it bitter. Its headline figure is about 175°F (80°C) for matcha in general, and I start a milk-drink base at the cooler range.

What the studies show

In a 2025 panel of nine trained tasters, standard Longjing leaf tea's bitterness rose from 3.13 to 5.17 out of 10 between 70 and 100°C water (Deng et al., 2025).

The panel brewed Longjing for 4 minutes at 70, 80, 90 and 100°C. Lower temperatures (70 to 80°C, with 70°C optimal) enhanced umami and reduced bitterness and astringency. Astringency rose from 2.07 to 4.13, which the authors tie to faster leaching of flavonols and their glycosides.

Source: Deng et al., Food Chemistry: X, 2025. Standard grade (the premium grade's bitterness rose 33%). Nine trained panelists, 4-minute brews tasted at 45°C, scores from 0 (very weak) to 10 (very strong). Leaf tea, not matcha.

Hotter water also pulls more phenolics from matcha itself. In 5-minute extractions of 3.0 g of ceremonial-grade matcha in 150 mL of water, total phenolics were 40.21 mg GAE (gallic acid equivalents) per 100 mL at 70°C and 56.81 at 100°C (Ali et al., 2026).

Source: Ali et al., Foods, 2026, Table 3, plain matcha, filtered, Folin-Ciocalteu assay. These are 3 g in 150 mL (1:50), a thinner brew than a bar shot. The same study's 5°C extract, stirred for 12 hours, gave 24.89. Total phenolics are linked to bitter and astringent taste, but this table is a chemistry result, not a taste score.

What the matcha panel found

The Ali et al. study was mainly about berry blends, and its 50 semi-trained panelists from a Saudi university scored liking, not bitterness, on extracts cooled to 25°C. Plain matcha's taste scores were nearly flat across 5, 70 and 100°C (8.10, 8.00 and 8.00 out of 9, with the same significance letters in the paper's Table 1), and overall acceptability stayed near 8. I found no panel that scored bitterness in plain matcha across temperatures, so use the bar check below as the real test.

How to check your bar

Check what your bar actually delivers. Put a thermometer in the water you use for matcha. A hot water tap or kettle set for coffee or tea may sit well above 150 to 160°F, and I don't know what yours reads. If it runs hot, temper it with cool water or set the kettle lower. For iced drinks, use cool or room-temperature water, as in our no-whisk guide.

Is the dose right for the drink?

As our matcha shot guide says, scoops pack differently from barista to barista, so weigh every dose and size it in whole shots. I plan every drink at 3 g of matcha, pulled at 1:15 in 45 ml of water. That's the house shot from that guide, and 3 g is the low end of the 3 to 4 g latte dose in the quick answer of our preparation guide. At 3 g, one kilogram makes about 333 drinks, and the order calculator turns your daily drinks into kilograms.

Match the shots to the cup: I'd use a double (6 g in 90 ml) for a large iced or boba cup, and a single for a standard latte. My working theory for a grassy latte is dilution: against a lot of milk, a thin dose may leave little but the green note. I haven't tested that, so the bar test below checks it. Keep the dose fixed in whole shots while you change the water, so you test one thing at a time.

Are you sifting every dose?

Sift every dose, even in a rush. As our no-whisk guide explains, matcha is milled leaf that spreads through liquid rather than dissolving, water can't get to every particle in a cluster, and what stays dry ends up as a gritty pocket in someone's drink. A small fine-mesh strainer over the pitcher or shaker is enough.

How old is your powder, and how long has the batch sat?

A tracked tea harvesting machine beside a hedge of tea bushes, with a strip of wild grass and bare soil in the foreground, on a farm in Shizuoka — Wild grass in the foreground, a tea hedge behind. Freshness starts at the farm, and the bar either keeps it or loses it.

Use color as a first clue, not proof of age. A vivid green powder looks fresh, and a dull olive or tan one can mean oxidation or a later harvest, a point our guide to matcha for cafes and lattes makes about lattes.

A 2026 review of matcha in foods says oxygen, light and storage conditions contribute substantially to pigment oxidation and color deterioration. Separately, it notes that matcha-enriched foods with substantial chlorophyll degradation often look dull or brownish and taste more bitter (Onder et al., 2026, a review in Foods). It covers matcha used in foods, not opened bags, so read it as a reason to watch the color, not as a shelf-life figure.

These habits need no equipment. Write the open date on every bag and use the oldest bag first. Keep the working container sealed, out of heat and light, and decant only what a shift needs. I don't have a tested figure for how fast an opened bag fades at a bar, so I won't give you a number of days. Judge it by color and by the cup.

A batch gets its own check. Matcha is milled leaf, not an extract, so it settles. Stir or shake the batch before every pour, keep it cold, and batch for the rush rather than the whole day. Our matcha concentrate guide has the recipe and the hold limits. If the first drink of the shift tastes better than the last, suspect the batch.

Does milk change how astringent matcha tastes?

Milk components softened astringency in lab tests, which is a reason to judge your fix in the milk you pour. In chilled catechin solutions, not matcha, the astringency suppression effect was about 58 to 65% in the three milk-component samples that left out lactose (Miura and Akuzawa, 2010, abstract).

A 2024 review adds that β-casein binding to catechins reduces the astringency of tea polyphenols in milk tea (Wijegunawardhana et al., 2024). Neither tested matcha, and the 2010 abstract scored astringency only. I found no study of how plant milks change matcha's taste, so test your fix in the milk you pour, hot and iced, not in a cup of water.

When is the fix a better grade?

Close view of a red tea harvesting machine's cutting head moving over a hedge of fresh green tea leaves in Shizuoka — A harvester working over a hedge in Shizuoka. Grade starts here, in how the leaf was grown and cut.

A better grade fixes bitter matcha only if a blind comparison in your own cups shows it, so compare grades after water, dose, sifting, powder age and batch are ruled out.

How shading changes the leaf

Shading is one of several things behind grade, alongside cultivar, harvest timing and processing. Matcha is shade-grown: nets cut sunlight by about 70 to 95% for the last 20 to 30 days before harvest, which suppresses catechin biosynthesis and promotes chlorophyll, L-theanine and other free amino acids. A 2026 review ties that to the enhanced umami taste and lower astringency of high-quality matcha (Onder et al., 2026).

The same review cites an analysis of matcha samples of different quality grades, in which high-quality samples had relatively high amino acid levels and relatively low catechin levels, and lower-quality samples the reverse.

What grade labels tell you

Ceremonial and culinary are informal trade labels, and I found no published standard that defines either, so the name on the bag tells you less than the cup does. A 2023 study describes ceremonial as the highest quality matcha for brewed drinks and culinary as more economical. In one brand's range, culinary matcha had total phenolics of 149.5 mg GAE per g of tea against 111.6 for ceremonial, with the same direction in two other brands. The authors note that ceremonial matcha is prized for a milder taste (Meyer et al., 2023).

From our tea room

Organic Ceremonial Matcha Powder - USDA Certified (30g)

Stone-milled ceremonial grade, USDA Organic, third-party lab tested.

View Ceremonial Matcha

Grade labels don't settle it, though. In the Longjing panel, the premium grade, made from younger and more tender leaf, had more polyphenols, caffeine and amino acids than the standard grade and scored higher on bitterness, astringency and umami. Its bitterness score rose less with heat, 33% from 70 to 100°C against 65% for the standard grade, but it still rose, and its umami score fell from 8.10 to 5.60 (Deng et al., 2025). That's leaf tea, not matcha, but it's a reason to compare grades in your own cups, not by label.

Which of our grades to compare

For a milk drink, I'd compare Latte Grade (Organic) with Ceremonial (Organic) in your own milk. For a straight whisked drink, I'd compare Ceremonial (Organic) with Superior or Royal, which are offered on request.

How do you test a fix on your own bar?

Change one thing at a time. Water first, then dose, then grade. If you change two, you won't know which one worked.
Weigh and sift the same 3 g every time. Pull each version in 45 ml of water, and measure the water's temperature with a thermometer.
Make each version in your own milk, hot and iced. Label the cups A, B and C, not by name.
Have two or three people taste and write one word per cup. Bitter, grassy, flat or sweet. Keep the version the room agrees on.

I haven't run this as a controlled study. It's a bar-side check so you decide on your own cups.

Frequently asked questions

Is matcha supposed to taste like grass?

A little, yes. Matcha is whole ground shade-grown leaf, so a fresh green note is normal. A sharp, raw-grass taste usually means something is off: check the powder's color and open date, then the dose against the milk, then the grade.

Why does my matcha taste bitter?

Check the water, then the dose and the grade, and test the fix in your own milk. Hotter water dissolves more total phenolics, a group linked to bitter and astringent taste: 3 g of ceremonial matcha in 150 mL released 41% more at 100°C than at 70°C (56.81 vs 40.21 mg GAE per 100 mL, Ali et al., 2026), though that study's panel scored liking and rated plain matcha's taste about the same at 5, 70 and 100°C.

Can a better grade fix bitter matcha?

No published test I found shows it, so compare blind. In one study, same-brand ceremonial matcha had lower total phenolics than culinary (111.6 vs 149.5 mg GAE per g), but that is not a taste score. Fix the water, dose, sifting and powder age first, then compare grades in your own milk.

Wholesale matcha for your bar

If you're fixing the cup behind a matcha menu, our wholesale terms are made for it. In-stock bulk starts at 1 kg, with the exact minimum confirmed in your quote, and ships from our US inventory, so you can run the bar test before you commit to a large order. Samples are available on request, and the sample terms come with your written quote.

Latte Grade (Organic) is 100% organic matcha with no sugar, no creamer and no premix, so the sweetness stays your recipe's call, and Ceremonial (Organic) is for straight whisked matcha and the signature drinks where the tea leads. Both are stocked in the US. Superior and Royal, our premium Uji ceremonial grades, are offered on request, with availability and lead time confirmed in your quote, and they are not organic certified.

When you buy through a broker, you're trusting a middleman's word on quality. When you buy from us, you're buying from someone who stood in the field where your tea was grown.

Submit the quote request form and my current price sheet opens right away. I read every quote request myself, and your written quote follows within 2 business days.

See matcha for cafes Request a quote and samples

Running a boba or milk tea shop? Grades and terms for your menu are on matcha for bubble tea shops.

About the author: I'm Christian Mauerer, founder of One with Tea. We import Japanese matcha into the US, including USDA Organic grades, and I visited tea farms across Japan, from Uji in Kyoto to Shizuoka and Kagoshima, documenting the people and the process for our documentary. The studies above are linked so you can read them yourself. The 3 g dose, the order of the checks and the bar test are my own starting points, not lab-tested standards, and our lab results page explains what we test our matcha for.

The regional picture is here: which Japanese prefectures actually grow the tea.