Brewing Basics & Parameter Quick-Reference

Brewing tea isn’t mysterious. A good cup mostly comes down to four variables: water temperature, leaf amount, time and vessel. Understanding how they interact beats memorising any single “standard.” Brewing isn’t a maths problem with one right answer; it’s a parameter-tuning problem with boundaries: once you grasp the basic relationships between water, leaf, heat and time, you can reliably brew the concentration and style you want for your own palate and the tea in hand.

A useful calibration habit is to change one variable at a time. If the cup is harsh, shorten the steep or cool the water first; if it is weak, modestly add leaf, time or heat. Temperature, time and leaf size all change extraction, so no single slogan replaces tasting[1][3]. The quick-reference table below lets you pick a tea category and toggle “Gongfu / Western” for suggested starting points:

How the four variables shape the cup

Brewing is essentially the transfer of soluble substances from leaf into water. Together, the four variables determine a cup’s concentration and component balance[1][3]:

• Water temperature changes extraction rate and balance. Raising it generally speeds the extraction of caffeine, polyphenols and other solubles. Whole leaf, roasted or compressed tea may start hotter; tender buds and broken leaf may benefit from cooler water or less time to control harshness[1][2]. This is not a rule that high heat “scalds” an entire category: tenderness, shape and processing vary within every type.
• Leaf amount (leaf-to-water ratio) is an important strength dial. For a longer everyday steep, try roughly 1.5–2 g / 100 ml; for gongfu, try roughly 4–8 g / 100 ml with much shorter repeated infusions. The broad span reflects leaf volume, integrity and target strength; these are not sensory-evaluation standard values[3].
• Time works with leaf amount, temperature and shape. Broken leaf extracts faster than whole leaf, while tightly rolled leaf may need time to open. Gongfu can start at a dozen or so seconds and everyday brewing at 2–4 minutes, then be corrected by tasting[1][2].
• Vessel affects heat and viewing: a glass is great for watching tender green tea unfurl; a gaiwan is versatile and gives fine control of temperature and timing; a Yixing pot retains heat well for oolong and dark tea; black tea often uses a porcelain pot[5].

A simplified framework:

Tea concentration ≈ f(temperature, time, leaf-to-water ratio, leaf brokenness)

Temperature, time and brokenness set the extraction rate; the leaf-to-water ratio sets the concentration ceiling. The four compensate for each other: more leaf can be balanced by less time, hotter water by less leaf, broken leaf by faster pouring.

Leaf-to-water ratio and concentration: an intuitive view

The leaf-to-water ratio is the easiest variable to overlook and the most powerful for repeatable results. It directly sets the cup’s concentration ceiling:

• 1 g / 100 ml (about 1:100): on the light side; good for large-cup long steeping or those who prefer a delicate cup.
• 2 g / 100 ml (about 1:50): a common everyday starting point, moderate in strength.
• 4–5 g / 100 ml (about 1:25–1:20): a gongfu starting point, paired with short steeps for rich but layered flavour.
• 8 g / 100 ml or more: high-concentration gongfu, suited to heavily roasted oolong, aged pu-erh and other durable teas.

The same tea brewed at 1:50 for 3 minutes and at 1:25 for 1.5 minutes may end up at a similar concentration, yet the cups will not be identical: the higher-ratio, shorter-time combination usually gives a more concentrated aroma and lower bitterness, while the lower-ratio, longer-time brew tends to give a fuller but flatter flavour.

Extraction kinetics in brief: why components move at different speeds

Tea constituents move from leaf into water as an approximately first-order process that approaches equilibrium: the extraction rate is proportional to how far the system still is from equilibrium, so extraction is fast at first and slows later[1][2]. Different constituents are not in step:

Two familiar experiences follow:

• Cooler water, softer cup. Overall, caffeine extracts faster than polyphenols such as black-tea theaflavins. At lower temperature both slow down, but caffeine still largely extracts within a short time while polyphenol accumulation is suppressed — bitterness remains, astringency recedes, and the cup tastes softer. This is a qualitative extrapolation from hot-water kinetics, and it runs in the same direction as the “sweeter, less bitter” character of cold-brewed tea.
• Broken leaf brews fast. Smaller particles mean more surface area and shorter diffusion paths, so rate constants rise[2]. CTC fannings therefore suit a shorter steep or cooler water, while whole, tightly rolled leaf can be given time to open.

The Arrhenius effect of temperature

Extraction rate rises with temperature according to the Arrhenius relationship:

k = A · exp(−Eₐ / RT)

where Eₐ is the activation energy. The activation energy for caffeine extraction is about 40 kJ/mol (similar values reported across teas), so temperature increases markedly speed extraction[3]. Different components have different activation energies: caffeine is relatively temperature-sensitive, while larger molecules such as theaflavins, theabrownins and pectin extract more slowly. This means changing temperature changes not only concentration but also the balance of bitterness, astringency and umami — higher temperatures favour strength and boldness, lower temperatures favour softness.

These are illustrative rate patterns; actual brewing is also affected by water quality, leaf condition and vessel, and the final parameters should still be set by tasting.

Leaf shape and brokenness: diffusion control

Tea extraction is not simple “dissolution” but diffusion inside a solid. Leaf shape directly determines the diffusion path length:

• Whole leaf / strip tea: cell structure is intact, so constituents must diffuse from the interior to the surface. Rate constants are smaller and the tea is more durable. Suited to high temperature, longer times or many gongfu infusions.
• Broken leaf / CTC: cells are largely ruptured and solutes are directly exposed. Rate constants are large and extraction is very fast. Suited to short steeps, cooler water or teabag-style brewing.
• Compressed tea: leaves are pressed together, so water penetration and leaf opening take time. The first steep is often a “wetting” or “rinse” to help the leaves unfold before normal extraction begins.

So brewing parameters should be chosen not only by tea category but first by leaf form. The same loose raw pu-erh and its cake version, the same whole Longjing and its broken dust, can need very different parameters.

Gongfu vs. Western: two concentration strategies

The reason gongfu can yield many infusions is that each steep extracts only part of the leaf’s solubles. After the first pour, plenty of material remains inside the leaf; concentration then decays roughly exponentially across subsequent steeps. Western brewing uses a low leaf ratio and long time to approach extraction equilibrium in one go, giving a strong cup but leaving less to extract later.

Neither is “better” — they are different aims: gongfu to explore the layers, Western for easy daily drinking.

Parameter-tuning decision tree

When a cup is not to your taste, adjust in this order:

Too bitter or astringent

• Lower the water temperature by 5–10 °C.
• Shorten the steeping time.
• Reduce the leaf amount.
• Pour faster and drain the leaves thoroughly.
• Check whether you are using broken leaf or CTC; if so, shorten further.

Too weak or thin

• Increase the leaf amount.
• Lengthen the steeping time.
• Raise the water temperature.
• Check whether compressed tea has not opened; give it a wetting steep.

Weak aroma

• Check whether the water temperature is too low (aroma volatiles need enough heat).
• Avoid long covered steeps that drive off low-boiling aromatics.
• Use an aroma-neutral vessel such as a gaiwan.
• Check whether the tea has been stored damp or absorbing odours.

Key principle: change only one variable at a time, taste, then decide the next move. Recording each session is the fastest way to improve consistency.

A simple brewing log template

For repeatable results, note the following each time:

Keeping notes for three to five sessions builds a “parameter feel” for that tea, freeing you from fixed slogans.

Cold, warm and hot brewing: choices across the temperature spectrum

Temperature affects not only speed but also the final balance in the cup:

• Hot brew (90–100 °C): caffeine and polyphenols extract quickly and fully, aroma is lifted, and the cup is bold and aromatic. Good for teas whose structure and fragrance you want to explore.
• Warm brew (60–80 °C): caffeine still extracts fairly quickly, but polyphenol extraction is suppressed, giving a softer, less astringent cup. Good for tender green teas or a lighter preference.
• Cold brew (4–10 °C, several hours): everything extracts very slowly at low temperature, but the relative proportions of caffeine and amino acids differ from hot brewing, often yielding a sweeter, less bitter cup with fresh, low-boiling aromatics dominant.

Cold brew is not a “healthier” or “superior” version; it is simply another extraction curve. Some teas shine cold, others need heat to reveal their aromatic backbone.

Echoing the craft

Why do some teas make sense as a hot-water starting point while others benefit from cooler or shorter brewing? Craft and oxidation affect composition and leaf structure, but tenderness, shape, roast, compression and the drinker’s goal matter too. Use the six crafts in “The Science” as context, then determine parameters by tasting.

Common misconceptions

1. “Green tea cannot take boiling water.” Within a category, tenderness and leaf shape matter; this is not an absolute ban. Premium tender green tea is safer at 80–85 °C, but a coarse pan-fired green can take boiling water.
2. “Rinsing tea detoxifies it.” Wetting only helps compressed leaves open; it does not “detoxify” tea or replace sound raw material and storage hygiene.
3. “The first infusion is always the weakest.” Not necessarily in gongfu: the first steep is often the most aromatic. In Western long steeping, the first pour is usually the strongest.
4. “Long covered steeping makes the tea richer.” Extended high-temperature steeping over-extracts polyphenols and caffeine, producing bitterness that overwhelms umami; this is not true richness.
5. “Good tea is forgiving no matter how you brew it.” Good tea has more margin for error, but careless brewing still wastes its layers; brewing is the final step that realises the leaf’s potential.

Related entries

• How water quality changes the cup — hardness, alkalinity and mineral ions
• The Science of each craft — how composition is preserved or transformed during processing
• Leaf chemistry — the forms of catechins, caffeine and theanine in the leaf

References

1. Spiro, M., Jaganyi, D., & Broom, M. C. (1992). Kinetics and equilibria of tea infusion. Part 9: The rates and temperature coefficients of caffeine extraction from green Chun Mee and black Assam Bukial teas. Food Chemistry, 45(5), 333–335. https://doi.org/10.1016/0308-8146(92)90033-X — Effect of temperature on the rate of caffeine extraction (temperature coefficients).
2. Price, W. E., & Spiro, M. (1985). Kinetics and equilibria of tea infusion: rates of extraction of theaflavin, caffeine and theobromine from several whole teas and sieved fractions. Journal of the Science of Food and Agriculture, 36(12), 1309–1314. https://doi.org/10.1002/jsfa.2740361216 — Extraction rates from whole leaf vs sieved broken fractions; theaflavin extracts more slowly than caffeine.
3. Jaganyi, D., & Price, R. D. (1999). Kinetics of tea infusion: the effect of the manufacturing process on the rate of extraction of caffeine. Food Chemistry, 64(1), 27–31. https://doi.org/10.1016/S0308-8146(98)00101-0 — Caffeine extraction at 80 °C: rate constant about 0.99 min⁻¹, activation energy about 40.3 kJ/mol; diffusion through the leaf matrix is strongly hindered.
4. GB/T 23776-2018. Methodology of sensory evaluation of tea. National Standard of the People’s Republic of China. — Cited to distinguish fixed sensory-evaluation conditions from this page’s everyday and gongfu starting points; the table is not a transcription of the standard.
5. Wan Xiaochun. Tea Biochemistry (3rd ed.). China Agriculture Press, 2003. — L-theanine and amino acids dissolve readily and early; volatility of aroma compounds and how the aroma profile evolves while brewing.

These are editorial starting points, not a national standard or quality judgment. Tenderness, leaf shape/compression, roast, storage, water and taste can all change the useful settings. Green tea normally needs no rinse; wetting can help compressed leaf open, but it does not “detox” tea or replace sound production and storage hygiene.