Carotenoids
The yellow-orange pigments hidden under the green — and the raw material for a good part of tea's fruit and floral aroma.
What a drinker notices
- Colour — appearance
Yellow-orange, visible in dried leaf and contributing to the colour of a whisked powdered tea. Fat-soluble and effectively absent from a steeped liquor, so in a normal cup they are seen in the leaf rather than in the water.
What this gets credited for, wrongly
Their aroma fragments are frequently credited to the pigments themselves. The pigments have no smell; what smells is what is left when they break, and the two are different compounds with a processing step between them.
What it is
Every tea leaf is yellow-orange underneath its chlorophyll; the green simply dominates until the chlorophyll goes. Carotenoids matter twice over in tea. They contribute to the colour of matcha and of dried leaf, and — much more interestingly — they are precursors: when they break down during withering, oxidation, sun-drying and roasting, the fragments left behind are aroma compounds with extremely low detection thresholds. A large part of the fruit, violet and woody character of oxidised and roasted teas comes from pigment being taken apart, which is one of the least obvious connections in tea chemistry.
Chemically: Fat-soluble yellow-orange tetraterpene pigments.
Where it occurs in the plant
Present throughout the leaf and masked by chlorophyll. Their level relative to chlorophyll rises as leaf matures and falls under shading, since shading raises chlorophyll faster.
What processing does to it
In tea, processing is not a modifier applied to a fixed composition — it is what decides the composition. These are the steps that move this compound, and each links to the step itself.
- Oxidation — Turns it into something else
- Degraded during oxidation, and the fragments are among the most potent aroma compounds in black tea. Pigment chemistry and aroma chemistry meet here.
- Sun-drying (shai qing) — Lowers it
- Sunlight breaks carotenoids down directly, which is one of the real compositional differences between a sun-dried maocha and a machine-dried one, and part of why sun-dried leaf smells the way it does.
- Shading — Lowers it
- Falls relative to chlorophyll under cover. Shaded leaf is greener partly because there is more green and partly because there is less yellow underneath it.
How brewing brings it out
Extraction rate: Not extracted by water at all
Fat-soluble and essentially not extracted by water. Like chlorophyll, they reach a drinker only where the whole leaf does.
Across infusions: Barely extracted at all in any infusion, being fat-soluble. What they contribute to a cup is what their breakdown products contribute, and those arrived during processing rather than during brewing.
Leaf, ratio and agitation: Relevant to matcha, koicha and culinary powdered tea, and to the appearance of dry leaf when buying. Irrelevant to the contents of a steeped cup.
What you can change
- Assess them by eye on the dry leaf
- Whisked or ground preparations are the only way they reach the cup
Where this gets misdescribed
That a tea's aroma comes only from compounds made as aroma. A good share of it is wreckage — pigments and lipids broken down by processing into fragments that happen to smell of fruit and flowers.
Teas this compound defines
Read next
- Beta-ionone — Violet and dried-fruit aroma from broken-down carotenoid pigment, detectable at some of the lowest levels in tea.
- Chlorophyll — The green of the leaf, and — because it barely dissolves — the reason a steeped green tea is yellow while a whisked one is green.
- Pheophytin — What chlorophyll becomes when heat or acid knocks the magnesium out — and the whole explanation for green tea going olive.
What this page does not say
This record describes pigments, their colour and their role as aroma precursors. It makes no statement about them as nutrients or about what they do in a body.
Sources
- TeaHQ editorial synthesis — TeaHQ
This page is TeaHQ’s own synthesis of well-established tea chemistry. No external technical document stands behind it, and that constraint is why there are almost no numbers here: directions, rankings and mechanisms are stated plainly, quantities are not, because a figure nobody can check would look more authoritative than it deserves.