Oolong & Black Tea
What Is Black Tea?
What is black tea? The fully oxidized tea category producing bold, malty, brisk flavors. From Assam CTC to Darjeeling estate teas, a complete overview.
Introduction
Black tea (called red tea in China, hong cha, for the color of its liquor rather than its leaves) is the world's most consumed tea category, accounting for approximately 70% of global production. It is defined by complete {{glossary:oxidation}} — 90-100% — which converts the leaf's catechins into {{glossary:theaflavins}} and thearubigins, creating the bold, malty, brisk flavors that characterize the category.
Processing
Black tea production follows the sequence of withering, rolling, oxidation, and firing. What distinguishes black tea processing is that the oxidation phase is allowed to run to near-completion. After rolling, leaves are spread on tables or troughs in a controlled environment (25-30 C, high humidity) for 1-3 hours until they reach the desired deep copper color and characteristic aroma. Firing at 80-90 C then halts the reaction.
Two Production Methods
{{glossary:orthodox-processing}}: Preserves leaf integrity through gentle rolling, producing a range of grades from whole leaf to fannings. Orthodox black teas are the specialty end of the market — Darjeeling, Keemun, Dian Hong, and premium Ceylon. {{glossary:ctc-processing}}: Crushes leaves into uniform granules for rapid, strong extraction. CTC dominates commercial production in India (Assam), Kenya, and Sri Lanka, optimized for tea bags and strong milk tea.
Major Producing Regions
India: Assam (bold, malty), Darjeeling (floral, muscatel), Nilgiri (bright, fragrant). China: Keemun (winey, smoky), Dian Hong/Yunnan (sweet, peppery, golden tips), Lapsang Souchong (pine-smoked). Sri Lanka (Ceylon): Classified by elevation — high grown (bright, citrusy), mid grown (balanced), low grown (full bodied, strong). Kenya: The world's largest black tea exporter, primarily CTC for global blending.
Flavor and Brewing
Black tea's fully oxidized chemistry means it tolerates boiling water (95-100 C) and longer steep times (3-5 minutes) without the harsh bitterness that plagues over-brewed green tea. This robustness, combined with its compatibility with milk and sugar, explains black tea's global dominance.