Cup reference

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Before Chapter 1 talks about plants and processing, and before Chapter 2 talks about how you feel, it helps to know what “a cup” even means. People say the phrase casually. Labs and home kitchens mean very different strengths. If the words on the box still feel disconnected from the chemistry, skim Tea basics first (aisle labels → processing paths), then come back here for milligrams.

This page standardizes on a 250 mL cup and lists typical lab and consumer-brew ranges from the source packs. Use it as a map, not a promise about your exact mug. When a module mentions “200 mg L-theanine,” come back here and compare: that lab capsule is often much stronger than one ordinary mug. Tap a footnote marker to jump to the source (and the caret to jump back). Hover often shows a popup.

Why the numbers move

Leaf quality, brand, and steep time move the numbers. Green and black tea also differ because of processing (see Module 1 · Brewing and Compounds): many catechins stay simple in green tea; in black tea many are linked into darker pigments, so EGCG and total catechins in the cup are usually much lower 12.

The table uses a common everyday baseline: 2 g dry leaf per 250 mL (one bag or a modest spoonful). Formal tasting (ISO 3103) uses about 2 g per 100 mL (about 5 g per 250 mL)—stronger than many home cups.

If your green tea tastes mild, you may be below these ranges. If your black tea keeps you up, you may be toward the high end of caffeine (about 40–80 mg in these sources for the black-tea row). Compare cups using the same volume when you can.

Typical yields (packs)

Compound Tea type Typical yield Usual brew in these sources Citation
Caffeine Green 30–50 mg 2 g leaf, 250 mL, 80°C, 3 min Chin et al. (2008) 3
Caffeine Black 40–80 mg 2 g leaf, 250 mL, 100°C, 3–5 min Hicks et al. (1996) 4
L-Theanine Green 15–30 mg (shaded Gyokuro or Matcha often 45–80 mg) 2 g, 250 mL, 80°C, 3 min Keenan et al. (2011) 5
L-Theanine Black 10–25 mg 2 g, 250 mL, 100°C, 3–5 min Keenan et al. (2011) 6
EGCG Green 50–120 mg 2 g, 250 mL, 80°C, 3 min Perva-Uzunalić et al. (2006) 7
EGCG Black 1–10 mg (most converted during oxidation) 2 g, 250 mL, 100°C, 3–5 min Del Rio et al. (2004) 8
Total catechins Green 100–300 mg 2 g, 250 mL, 80°C, 3 min Bhagwat et al. / USDA flavonoid database 9
Total catechins Black 10–50 mg (many linked into darker pigments) 2 g, 250 mL, 100°C, 5 min Lakenbrink et al. (2000) 10

Keenan’s group measured L-theanine in real 200 mL cups after a two-minute steep and found brew time was the biggest dial—ordinary black tea often landed near 24 mg, with lower averages for some greens in that particular sample set 11. Pack ranges above blend those findings with other consumer-brew notes so a 250 mL home cup stays easy to compare.

NoteTea vs coffee caffeine (qualitative)

On this site, everyday tea cups in the table above land in the tens of milligrams of caffeine (roughly 30–80 mg for the green/black rows). A large coffee is usually described as a stronger caffeine hit than those tea rows—which is why Module 2 can say tea is often “less caffeine than a large coffee” plus a second compound coffee does not share. Exact coffee milligrams are pack-silent here; we do not invent a coffee column. Compare tea numbers to the table above, not to an unverified cafe estimate.

Practical notes (still from the packs)

Water temperature. Hotter water pulls more catechins. Steeping green tea at 100°C instead of 80°C can raise total catechin yield by about 25%, but it also pulls more bitter material and can hurt taste 12. That is the same brew-temperature thread Chapter 1 uses when it talks about EGCG needing heat.

Why 250 mL? Papers often use 200 mL or 250 mL. This site standardizes on 250 mL so comparisons stay consistent.

Leaf amount. Formal tasting (ISO 3103) uses about 2 g per 100 mL (about 5 g per 250 mL). The table above uses a common everyday baseline: 2 g dry leaf per 250 mL cup (one bag or modest spoonful).

Beginner tip. When you read Chapter 2 study doses like “200 mg L-theanine,” compare them to this table: a typical green cup here is about 15–30 mg L-theanine (shaded Gyokuro or Matcha often 45–80 mg). Lab capsules are often much stronger than one ordinary mug.

Formal sensory preparation under ISO 3103:2019 uses about 2 g tea per 100 mL freshly boiling water (about 5 g per 250 mL)—brew times on the order of 6 minutes for black tea and 3–5 minutes for green depending on leaf grade.13 Many home cups use closer to 2 g per 250 mL. That single difference can move caffeine and theanine yields a lot before brand even enters the story.

Keenan’s group measured L-theanine in real 200 mL cups after a two-minute steep and found brew time was the biggest dial—ordinary black tea often near 24 mg L-theanine in that design.14 Pack ranges in the table blend those findings with other consumer-brew notes for a 250 mL everyday baseline.

When Chapter 2 says “200 mg L-theanine,” compare to this page: a typical green cup here is about 15–30 mg (shaded Gyokuro/Matcha often 45–80 mg). Lab capsules are often much stronger than one ordinary mug.

From here, the natural next stop is Module 1 hub—how those numbers got into the water in the first place. Still puzzled by sencha vs English Breakfast? Open Tea basics.

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Footnotes

  1. Perva-Uzunalić, A., et al. (2006). Extraction of active ingredients from green tea (Camellia sinensis): Extraction efficiency of major catechins and caffeine. Food Chemistry, 96(4), 597–605. https://doi.org/10.1016/j.foodchem.2005.03.015↩︎

  2. Del Rio, D., et al. (2004). HPLC-MSⁿ analysis of phenolic compounds and purine alkaloids in green and black tea. Journal of Agricultural and Food Chemistry, 52(10), 2807–2815. (Pack-cited for EGCG in black tea.)↩︎

  3. Chin, J. M., et al. (2008). Caffeine content of brewed teas. Journal of Analytical Toxicology, 32(8), 702–704.↩︎

  4. Hicks, M. B., et al. (1996). Tea preparation and its influence on methylxanthine concentration. Food Chemistry, 56(4), 425–428. (Pack-cited for black-tea caffeine.)↩︎

  5. Keenan, E. K., et al. (2011). How much theanine in a cup of tea? Effects of tea type and method of preparation. Food Chemistry, 125(2), 588–594. https://doi.org/10.1016/j.foodchem.2010.08.071↩︎

  6. Keenan, E. K., et al. (2011). How much theanine in a cup of tea? Effects of tea type and method of preparation. Food Chemistry, 125(2), 588–594. https://doi.org/10.1016/j.foodchem.2010.08.071↩︎

  7. Perva-Uzunalić, A., et al. (2006). Extraction of active ingredients from green tea (Camellia sinensis): Extraction efficiency of major catechins and caffeine. Food Chemistry, 96(4), 597–605. https://doi.org/10.1016/j.foodchem.2005.03.015↩︎

  8. Del Rio, D., et al. (2004). HPLC-MSⁿ analysis of phenolic compounds and purine alkaloids in green and black tea. Journal of Agricultural and Food Chemistry, 52(10), 2807–2815. (Pack-cited for EGCG in black tea.)↩︎

  9. Bhagwat, S., et al. (2011 / USDA releases). USDA Database for the Flavonoid Content of Selected Foods. https://www.ars.usda.gov/ARSUserFiles/80400525/Data/Flav/Flav3.3.pdf↩︎

  10. Lakenbrink, C., et al. (2000). Flavonoids and other polyphenols in consumer brews of tea and other caffeinated beverages. Journal of Agricultural and Food Chemistry, 48(7), 2575–2582. (Pack-cited for black-tea catechins.)↩︎

  11. Keenan, E. K., et al. (2011). How much theanine in a cup of tea? Effects of tea type and method of preparation. Food Chemistry, 125(2), 588–594. https://doi.org/10.1016/j.foodchem.2010.08.071↩︎

  12. Perva-Uzunalić, A., et al. (2006). Extraction of active ingredients from green tea (Camellia sinensis): Extraction efficiency of major catechins and caffeine. Food Chemistry, 96(4), 597–605. https://doi.org/10.1016/j.foodchem.2005.03.015↩︎

  13. International Organization for Standardization. (2019). ISO 3103:2019 — Tea — Preparation of liquor for use in sensory tests. https://www.iso.org/standard/73224.html↩︎

  14. Keenan, E. K., et al. (2011). How much theanine in a cup of tea? Effects of tea type and method of preparation. Food Chemistry, 125(2), 588–594. https://doi.org/10.1016/j.foodchem.2010.08.071↩︎