Tea basics
You stand in a grocery aisle. Boxes say English Breakfast, Earl Grey, green tea, chamomile, matcha. Cafe menus add sencha, oolong, Assam. The companion chapters start talking about Camellia sinensis, oxidation, and catechins. How do those everyday labels connect?
This page is the bridge. It is not a second chemistry textbook and not a shopping guide. It maps common commercial names onto the plant and processing ideas that Chapter 1 uses—so when Module 1 says “green vs black,” you already know what your supermarket box probably meant.
Keep the Glossary for chapter jargon (HPA axis, ERN, BART). Keep the Cup reference for typical milligrams in a 250 mL mug. Use this page when a label on a shelf feels disconnected from the story.
Tap a footnote number to jump to the source, then the caret to jump back. Hover often shows a popup. Denser side-stories sit in collapsed “More detail…” foldouts.
- True tea vs herbal — Camellia leaf (green/black/oolong/white…) vs chamomile/peppermint/rooibos tisanes.
- Green / black fork — same plant; heat early (green) vs let it brown in air (black).
- One label example — English Breakfast is usually a strong black blend; sencha is everyday Japanese green.
- Numbers — when someone quotes milligrams, open the Cup reference.
The rest of this page is optional depth for when a shelf still feels foggy.
- True tea — an infusion from the tea plant Camellia sinensis (green, white, oolong, black, dark/Pu-erh, and so on).
- Herbal “tea” / tisane — hot-water infusions of other plants (chamomile, peppermint, rooibos…); usually no caffeine from Camellia.
- Oxidation — leaf enzymes plus air that darken catechins (tea people often say “fermentation,” but for ordinary green/black tea they usually mean this).
- Orthodox vs CTC — two black-tea factory styles: larger twisted leaf vs small fast-brewing granules.
What “tea” means on a commercial label
In everyday English, “tea” can mean almost anything steeped in hot water. In the science and trade language this site uses, true tea means leaves (and sometimes buds) of one species: Camellia sinensis.
That single plant is why Chapter 1 can say “one species, two main types” and still cover most of what you buy as green or black. Herbal boxes that say “tea” on the front—chamomile, peppermint, ginger, rooibos—are usually infusions of other plants. They can be lovely. They are not the same chemical story as caffeine, L-theanine, and EGCG from Camellia. FDA consumer materials have long noted that herbal teas come from other plants and should name the plant on the label.1 Trade groups likewise ask shoppers to keep “tea” for Camellia styles (green, black, oolong, white, dark) and call the rest herbals or tisanes.2
So when Module 1 talks about what is in your mug, it assumes a Camellia leaf unless it says otherwise. A caffeine-free “bedtime tea” made of chamomile is a different drink—and a different chapter of chemistry.
English borrowed the word tea for the Camellia drink, then stretched it to any hot infusion. That stretch is fine at a cafe counter. It becomes confusing in a science companion, because caffeine, L-theanine, and EGCG are signature Camellia characters—not universal “anything in a mug” characters.
Pack baseline for this site: commercial tea in Module 1 means Camellia sinensis. Herbal infusions are outside that chemical core unless a pack explicitly brings them in (this companion does not invent herbal dosing or economics).
Style map: processing paths, not different species
Green, white, oolong, black, and dark (Pu-erh) teas are mostly different factory paths on the same plant—not different species on the shelf. Chapter 1’s central fork is the same idea in two big strokes: stop the leaf enzymes early with heat (green path) or let them work with air (black path).
A useful mental ruler is how far enzymatic oxidation is allowed to run before heat locks the leaf:
| Everyday style | Rough processing idea | What you usually notice in the cup |
|---|---|---|
| Green | Heat early (steam or pan-fire) to stop browning enzymes | Pale to yellow-green; grassy/vegetal; catechins stay mostly “simple” |
| White | Minimal handling; young buds/leaves wilted and dried | Light color; delicate; least “factory drama” |
| Oolong | Partial oxidation (a wide band—light to quite dark) | Between green and black; floral to roasted depending on style |
| Black | Full enzymatic oxidation, then dry | Amber to deep red-brown; malty/brisk; many catechins linked into darker pigments |
| Dark (e.g. Pu-erh) | Extra microbial aging/fermentation after a tea base | Earthy, aged character; true microbes matter here |
The UK Tea & Infusions Association puts the same idea simply: length—or absence—of oxidation during processing is what separates black, green, oolong, and white character.3 Reviews of tea chemistry agree that style labels track processing more than species.4
Honesty from the packs: tea makers often say “fermentation” for the green→black change. Biochemically, ordinary oolong and black tea are aerobic enzymatic oxidation (leaf enzymes + air). True microbial fermentation shows up mainly in post-fermented dark teas such as Pu-erh.5
Trade and standards writing sometimes list six manufactured types (green, yellow, white, oolong, black, dark), sorted by processing and oxidation (see footnote on six-type framing in the References). Yellow tea is rare outside China and follows a green-like path with an extra “smothering/sweating” step; this companion does not need you to master it before Module 1.
Oolong oxidation is a range (often described from roughly ~10% to nearly ~80% depending on style), not a single midpoint. That is why one cafe “oolong” can taste almost green and another almost black—still one plant, different stopping points.
Six-type processing lists appear across tea-processing overviews and ISO classification work.6
So when a box says green or black, it is usually naming a process, not a different botanical species. That is the sentence Chapter 1 builds on.
Common grocery and cafe names → what they usually mean
Labels mix three things: place (Assam, Darjeeling), factory style (sencha, matcha), and blend or flavor recipe (English Breakfast, Earl Grey). The table below is a translation sheet—not a guarantee that every brand uses the name the same way.
| Label you see | What it usually means | Bridge into this site |
|---|---|---|
| English Breakfast | A blend of black teas chosen for a strong morning cup (often Assam and/or other robust blacks; recipes vary by brand) | Black-tea processing path; caffeine often toward the higher end of everyday cups—see Cup reference |
| Assam | Black tea from Assam (northeast India); often malty and strong; the region is the home story of the large-leaf assamica type | China-type vs Assam-type in Chapter 1 |
| Darjeeling | Tea from Darjeeling (Himalayan foothills); often delicate, high-grown; sold as black tea though some lots sit toward lighter oxidation | Geography + processing; not a separate species |
| Earl Grey | Usually black tea flavored with bergamot (citrus aroma); the base is still Camellia black tea | Flavoring on top of a black path—not a new plant |
| Ceylon / Kenyan | Black teas named for origin (Sri Lanka; Kenya)—common building blocks in blends | Origin labels ≠ different species |
| Sencha | Everyday Japanese green tea: leaves are typically steamed, then rolled and dried | Green path (heat stops enzymes early) |
| Matcha | Shade-grown green tea processed into fine powder you whisk into water (you drink the leaf, not only an infusion) | Pack note: shaded matcha/gyokuro often yield higher L-theanine in cup ranges—see Cup reference |
| Jasmine green | Green tea scented with jasmine blossoms; base is still green Camellia | Scenting ≠ herbal tisane |
| Oolong (Tieguanyin, Baozhong, etc.) | Partially oxidized Camellia tea; style names mark tradition and oxidation level | Middle of the oxidation ruler |
| Pu-erh / dark tea | Yunnan (and related) dark teas with microbial aging; “raw” vs “ripe” methods differ | Pack’s true-fermentation exception |
| Chamomile / peppermint / rooibos “tea” | Herbal infusions—not Camellia unless the label also lists tea leaf | Outside Module 1’s chemical core |
Usual meanings for blends, origins, and green styles follow the UK Tea & Infusions Association type pages cited above; sencha and matcha processing notes also match Japanese industry summaries;7 matcha/gyokuro theanine ranges sit on the pack Cup-reference baseline.8
English Breakfast is a recipe family, not a single garden. Blenders combine origins for color, strength, and milk-friendliness; two supermarket boxes can share the name and still differ.
Matcha vs sencha: sencha is steeped and the leaves are usually discarded; matcha is suspended powder, so more of the leaf solids enter the drink. Pack cup ranges already flag shaded gyokuro/matcha as often higher in L-theanine than ordinary green infusions.
Gunpowder, Keemun, Lapsang Souchong, Yunnan: more green or black style names you may see on shelves—still Camellia processing traditions, not separate species.
China-type vs Assam-type in plain language
Chapter 1’s first big plant idea is simple: almost all commercial tea is one species—Camellia sinensis—with two main “flavors” of plant, the way dogs are one species with many breeds.9
- China type (var. sinensis): smaller-leaved shrub; often linked with cooler hills; on average often richer in L-theanine.
- Assam type (var. assamica): larger-leaved, more tree-like; loves warm humid lowlands; on average often higher in caffeine and polyphenols.
Why grocery labels care: the word Assam on a box usually points to a region famous for assamica black tea. Darjeeling and many Chinese greens lean on sinensis-type material. Blends muddy the line—your “English Breakfast” may mix origins on purpose.
Honesty from the packs: “Assam always has far more caffeine” is too blunt. Averages often lean assamica-higher, but shade, fertilizer, and which leaf you pick can flip a single comparison.10 Chapter 1 walks that caveat with numbers; this page only needs the map.
→ Full story: Lesson 1.1 — Two plants, one species
Bag vs loose leaf, and CTC vs orthodox
Two separate questions get tangled on the shelf.
1. Bag vs loose is mostly about portion and particle size, not a different plant. A bag is a pre-measured serving; loose leaf is the same plant sold by weight. Bags often use smaller particles so color and strength appear quickly in a mug. The Cup reference models a common everyday baseline of about 2 g dry leaf per 250 mL—roughly one bag or a modest spoonful—while formal tasting (ISO 3103) uses a stronger ratio.11
2. Orthodox vs CTC is a black-tea factory distinction (how the leaf is broken before/during oxidation), not a green-tea rule.12
| Orthodox | CTC (crush, tear, curl) | |
|---|---|---|
| Leaf form | Larger twisted or broken leaf pieces | Small, uniform granules |
| Brew habit | Slower, often more layered | Fast, strong, deep color—common in bags and milk tea |
| Mental picture | Roll and bruise | Shred for speed |
UK trade pages describe orthodox rolling for larger grades and “unorthodox” CTC (or similar) machines that chop leaf into smaller particles for quicker brewing—exactly what many modern bag markets want.
Neither method invents a new species. Both can feed an “English Breakfast” blend. Particle size and blend recipe move the cup as much as the print on the box—another reason Module 1 refuses a single caffeine number for “tea.”
Smaller particles expose more surface area, so soluble solids—including caffeine and pigments—move into water faster. That does not automatically mean “more caffeine forever”; it often means a darker, brisker cup in the short steep times people use on a weekday morning. Pack extraction notes in Chapter 1 (temperature, time, leaf amount) are the dials; bag vs loose is one more dial, not a moral ranking.
How this page connects to Cup reference and Chapter 1
Read this site as three nested maps:
- Tea basics (this page) — what the words on the box usually mean.
- Chapter 1 — what the leaf and factory do chemically (China/Assam types; stop vs run oxidation; brewing; caffeine, L-theanine, EGCG).
- Cup reference — typical milligrams in a 250 mL cup under pack brewing baselines.
A short path many readers like:
- See English Breakfast → black blend → Cup reference black-tea caffeine row (about 40–80 mg in pack baselines) → Chapter 1 oxidation story.
- See sencha or matcha → green path → Cup reference green rows (and the matcha/gyokuro L-theanine note) → Chapter 1 heat-kill / catechin story.
- See chamomile tea → herbal infusion → not the Module 1 chemical core.
When you want chapter jargon (PPO, theaflavins, HPA axis), open the Glossary. When you want how brewing facts stitch to mood or decisions, open Linkages.
Where to go next
New to tea labels? You are in the right place. Ready for the chemistry story those labels sit on? Start Chapter 1: The Chemical Core. Want numbers for a standard mug first? Open the Cup reference.
Footnotes
U.S. Food and Drug Administration. (1996). Tea: A story of serendipity. FDA Consumer. https://permanent.access.gpo.gov/lps1609/www.fda.gov/fdac/features/296_tea.html (Notes that herbal teas are made from leaves of other plants and should name the plant.)↩︎
Tea Association of the USA. (2019). Comment on FDA food standards of identity modernization (Docket FDA-2018-N-2381): true tea from Camellia sinensis (green, black, oolong, white, dark) vs herbal tisanes. https://downloads.regulations.gov/FDA-2018-N-2381-1376/attachment_1.pdf↩︎
UK Tea & Infusions Association. Types of tea, origins & varieties. https://www.tea.co.uk/types-of-tea (Black/green/white/dark overview; English Breakfast and Earl Grey as black-tea blends; sencha steaming vs pan-firing; Pu-erh notes.)↩︎
Wong, M., et al. (2022). Phytochemical profile of differently processed tea: A review. Journal of Food Science. https://doi.org/10.1111/1750-3841.16137 (Green / white / oolong / black / pu-erh as processing categories.)↩︎
Source packs (Module 1 verification): ordinary oolong/black “fermentation” is enzymatic oxidation; true microbial fermentation mainly in post-fermented teas such as Pu-erh. See also Subramanian et al. (1999) and Tanaka & Kouno (2003) as cited in Chapter 1.↩︎
Processing overviews commonly list six manufactured types (green, yellow, white, oolong, black, dark) sorted by processing and oxidation—e.g. the tea-processing chapter in Food Reviews International (https://doi.org/10.1080/87559129509541052) and ISO tea-type classification work (ISO 20715:2023).↩︎
Kyoto Prefectural Tea Industry Chamber. Types of tea (sencha; matcha/tencha). https://www.ujicha.or.jp/en/knowledge/kinds/↩︎
Keenan, E. K., et al. (2011). How much theanine in a cup of tea? Food Chemistry, 125(2), 588–594. https://doi.org/10.1016/j.foodchem.2010.08.071 (Pack cup-reference baseline; shaded gyokuro/matcha noted higher.)↩︎
Wight, W. (1959). Nomenclature and taxonomy of the tea plant. Nature, 183(4677), 1726–1728. (Pack-cited naming frame for China-type vs Assam-type talk.)↩︎
Pack Module 1 verification note on caffeine averages vs growing conditions; Takeda (1994) cultivar survey as used in Chapter 1.↩︎
International Organization for Standardization. (2019). ISO 3103:2019 — Tea — Preparation of liquor for use in sensory tests. https://www.iso.org/standard/73224.html (Formal ~2 g / 100 mL vs everyday ~2 g / 250 mL baseline on Cup reference.)↩︎
UK Tea & Infusions Association. Creating the perfect blend (orthodox rolling vs CTC / unorthodox smaller particles for quicker brew). https://www.tea.co.uk/tea-processing-and-blending↩︎