TeaHQ

Bruising (shaking)

Deliberate, repeated agitation that damages the leaf edges so oxidation begins there and nowhere else.

搖青Stage 3 of 13: BruisingAlso called shakingAlso called tossingAlso called rattling

The categories this step defines

In tea, processing is not a modifier applied to a category — it is what creates the category. These are the types that exist because this step exists.

  • Oolong — Deliberate bruising to initiate edge oxidation, halted partway, frequently followed by roasting.

What it is

Withered leaf is tumbled in bamboo drums or tossed by hand, over and over, with rests in between. The impacts rupture cells along the leaf margin while leaving the centre intact, so oxidation starts at the rim and works inward under the maker’s control. A finished oolong leaf held to the light often shows this directly: a reddened border around a still-green middle, sometimes called the green leaf with a red edge. The number of shakes, their vigour and the length of the rests between them are the main levers an oolong maker has, and they are judged largely by smell.

Also transliterated as: yao qing, yaoqing.

What it does to the leaf

Ruptures cells selectively at the leaf margin, initiating localised enzymatic oxidation while the leaf centre remains unoxidised.

What it does to the cup

Builds the floral, orchid and stone-fruit aromatics that distinguish oolong from both green and black tea; heavier bruising pushes towards honeyed and fruity character.

Variants that matter

Ways this step is carried out that produce genuinely different results, rather than regional names for the same thing.

Hand tossing in baskets
Traditional and still used for small-batch Wuyi and Anxi production; slower, and highly dependent on the maker’s judgement.
Drum tumbling
Mechanised rotation gives repeatable agitation across larger batches, at some cost to batch-by-batch nuance.

Where this gets misdescribed

Bruising is often described as simply 'partial oxidation', as though the leaf were oxidised uniformly and then stopped halfway. The distinction matters: oolong is not a uniformly half-oxidised leaf but a leaf oxidised heavily at the edges and barely at all in the centre.

Other steps at the Bruising stage

  • Leafhopper feeding damage (zhu xian) — A small green leafhopper feeds on the growing shoot and the plant answers. The answer is the raw material: shoots that have been fed on are picked in that state, and a tea made from undamaged leaf on the same bush is a different tea.

Teas that go through this step

Guides covering this step

  • What is oolong tea? — Partially oxidised tea, bruised deliberately and often roasted. It is the widest-ranging category in tea, and calling it 'halfway between green and black' is the most misleading simplification in the subject.
  • Why oolong can taste floral — Because bruising the leaf edges and letting oxidation run partway generates aromatic compounds that neither green nor black tea produces — and because stopping at the right moment is a judgement made by smell.
  • The day after picking, hour by hour — Almost everything that determines what a tea will be happens within about thirty hours of the leaf leaving the bush. Following one basket of leaf through that period is the most direct way to understand why the categories exist.
  • How oolong is made, and why it is the most labour-intensive category — Oolong is not a tea that was oxidised halfway. It is a leaf oxidised heavily at its edges and barely at all in its centre, produced by a cycle of shaking and resting that runs through the night and is judged entirely by the maker’s nose.
  • Volatile aroma compounds, and why they are the most fragile part of a tea — Hundreds of volatile compounds have been identified in tea, most of them present in tiny quantities and most of them generated during processing rather than present in the fresh leaf. They supply nearly all of what people call flavour, and they are the first thing any tea loses.
  • One fresh leaf, and every decision that follows it — Follow a single plucked shoot from the basket and take the forks one at a time. Each answer closes some doors permanently and opens others, and by the fifth answer the tea has a name.
  • Reading a processing description on a packet — Most of what a packet says about processing is either a translation artefact, a marketing term, or a genuine and checkable fact. Telling the three apart is a learnable skill and it is worth more than any tasting note.
  • Reading a wet leaf backwards to the process — The spent leaf in the bottom of the pot is the most honest document a tea comes with. Almost every processing decision leaves a mark on it, and reading those marks is a skill that takes an afternoon to start and rewards a lifetime.

Sources

  • TeaHQ editorial synthesis — TeaHQ

This page is TeaHQ’s own synthesis of well-attested production practice. No external technical document stands behind it, so it describes what producers do rather than asserting measured process parameters.

How TeaHQ handles sources

Written comparisons

Where TeaHQ has set this step against something it is routinely confused with, and argued the differences out in full.

  • Rolling vs bruising — Both steps damage the leaf on purpose so that oxidation can proceed, and they damage it in completely different geometries. Rolling ruptures cells throughout and gives the leaf its selling shape; bruising ruptures cells only at the margin and leaves the middle untouched.