Citrus × junos Sieb. ex Tanaka (syn. Citrus junos Tanaka)
Appearance
colorless to yellow clear liquid
Odor Strength
High
Producing Countries
Japan (Kochi, Tokushima, Ehime prefectures), South Korea (Jeollanam-do), China (Yunnan, Sichuan, Hubei)
Pyramid
Top
Crushed rind, tart zest, a trace of sulfur. Yuzu smells like grapefruit peel blended with mandarin and pressed into damp herbs — citrus that is green and angular, never sweet. The identity compound, yuzunone, exists in no other commercially traded citrus species.
Tart, angular, green-bitter. The opening is rind-forward — grapefruit zest crossed with mandarin peel, but drier and more herbal than either. A sulfurous flash (common in expressed citrus) vanishes in seconds. Underneath the citrus bite, gamma-terpinene contributes a thyme-like herbal warmth absent from lemon or lime. Less sweet than bergamot, less acidic than lemon, less tropical than mandarin. Compared to combava (petitgrain combava), yuzu is less aldehydic and less rosy — it stays in citrus-herbal territory rather than drifting toward citronella. The drydown is clean, faintly woody-green, with a trace of waxy persistence from heavier sesquiterpene fractions.
Evolution over time
Immediately
Immediately
Sharp citrus-rind burst — grapefruit bitterness, mandarin zest, a brief sulfurous flash. Green-herbaceous from gamma-terpinene (thyme-like warmth). Angular, not sweet.
After a few hours
After a few hours
Citrus softens into a drier, more terpenic register. The herbal quality becomes dominant. Faint woody undertone from beta-farnesene. Less acidic, more aromatic.
After a few days
After a few days
Clean, faintly waxy-green residue. More persistent than lemon oil but lighter than petitgrain. Dry, austere, barely perceptible.
Terroir & Expressions
Indicative 2025 wholesale prices.
The Full Story
Yuzu (Citrus junos Sieb. ex Tanaka) is a natural F1 hybrid between a mandarin orange subspecies (mangshanyeju) and Ichang papeda (Citrus ichangensis), originating in the mountainous interior of central China. It reached Japan and Korea between the 6th and 8th centuries. The correct binomial notation is Citrus × junos, reflecting its hybrid origin — Tanaka classified it as a species (C. junos) in 1921, but molecular marker analysis has since confirmed the papeda-mandarin parentage. The fruit is small, bumpy-skinned, intensely aromatic, and nearly inedible raw.
Chemistry
Cold-pressed yuzu peel oil is dominated by limonene (approximately 78% by GC-MS), with gamma-terpinene as the second major constituent (9–14%). Minor components include beta-myrcene (~1.8%), alpha-pinene (~1.3%), delta-elemene, p-cymene, and the sesquiterpene (E)-beta-farnesene. Linalool is present only at trace levels (~0.03%), unlike in most other citrus peel oils. The identity compound is yuzunone — (6Z,8E)-undeca-6,8,10-trien-3-one — a conjugated trienone first identified by Sawamura et al. (2009) that has not been found in any other commercially traded Citrus species. Though present at very low concentration, yuzunone is a high-impact odorant contributing the green-balsamic quality that distinguishes yuzu from grapefruit or mandarin.
Distinction from Other Citrus
Yuzu oil is not phototoxic. Unlike bergamot, expressed lime, and bitter orange peel oils, cold-pressed yuzu contains no detectable bergapten (<0.1 ppm detection limit). This makes it one of the few expressed citrus oils that can be used in leave-on products without IFRA phototoxicity restrictions. The high gamma-terpinene content and very low limonene-to-terpinene ratio give yuzu a more herbaceous, less candy-sweet character than lemon or sweet orange. The presence of beta-farnesene (a sesquiterpene, MW 204) grants slightly better tenacity on skin than lighter citrus oils built purely on monoterpene hydrocarbons.
Production
Japan is the primary producer. Kochi prefecture alone accounts for approximately 51% of national yuzu output (Ministry of Agriculture, Forestry and Fisheries, 2021 data: ~23,000 tonnes nationally). Korea and southern China produce smaller quantities. Oil yield by cold pressing is roughly 0.67% — about 300 kg of grated peel per 2 kg of oil — making yuzu expensive relative to lemon or orange. CO2 supercritical extraction produces a fundamentally different oil (limonene drops to 1.6–2.0%, oxygenated terpenes dominate) and is not interchangeable in formulation.
This note in Première Peau. Gravitas Capitale · Nuit Elastique · Rose Monotone. Sample all seven extraits in the Discovery Set.
Yuzunone — (6Z,8E)-undeca-6,8,10-trien-3-one — was identified by Sawamura et al. in 2009 as the first character-impact compound unique to yuzu peel oil. It occurs in no other commercially traded Citrus species. The molecule is a conjugated trienone, structurally unusual for a citrus volatile, and contributes the green-balsamic quality that makes yuzu smell like yuzu and not like grapefruit.
Extraction & Chemistry
Extraction method: Cold pressing (expression) of Citrus junos peel. The fruit rind is mechanically scarified to rupture oil glands in the flavedo; the released oil is separated from juice by centrifugation. Yield is approximately 0.67% — roughly 300 kg of grated peel per 2 kg of oil — making yuzu one of the lower-yielding citrus oils. Steam distillation of the peel produces a slightly different profile (more terpenic, less aldehydic). CO2 supercritical extraction yields an oil with a fundamentally altered composition — dramatically lower limonene (1.6–2.0%) and higher oxygenated terpenes — and should not be considered interchangeable with expressed oil. Major production: Japan (Kochi prefecture accounts for approximately 51% of national output), with smaller production in Korea and China.
Not assigned (expressed peel oil). CAS 233683-84-6 applies to Citrus junos juice/leaf oil, not the peel oil used in perfumery.
Botanical Name
Citrus × junos Sieb. ex Tanaka (syn. Citrus junos Tanaka)
IFRA Status
Not restricted for phototoxicity. Cold-pressed yuzu oil contains no detectable bergapten (<0.1 ppm), unlike bergamot or expressed lime. Citral content requires EU allergen declaration above threshold in leave-on products (EU Regulation 2023/1545).
Synonyms
YUZU · YUJA (유자, Korean) · CITRUS JUNOS · CITRUS × JUNOS · JAPANESE CITRUS · HANA YUZU (ornamental variety)
Physical Properties
Odor Strength
High
Lasting Power
24 hours
Appearance
colorless to yellow clear liquid
Specific Gravity
0.830–0.860 @ 20 °C
Refractive Index
1.460–1.490 @ 20 °C
In Perfumery
Top-note modifier and citrus complexifier. Yuzu peel oil provides a tart, bitter-herbaceous brightness distinct from the fruity sweetness of orange or the acid sharpness of lemon. Its identity rests on yuzunone — (6Z,8E)-undeca-6,8,10-trien-3-one — a conjugated trienone first identified by Sawamura et al. (2009) that exists in no other commercially traded citrus oil. This molecule, present at trace concentrations, imparts a green-balsamic undertone that separates yuzu from every other hesperidic material. The oil's limonene dominance (~78%) is typical of citrus, but the supporting cast — gamma-terpinene (9–14%), beta-farnesene, alpha-pinene — creates a terpenic complexity unusual for an expressed peel oil. Beta-farnesene (MW 204, sesquiterpene) also grants slightly better tenacity than lemon or lime oils, which rely almost entirely on lighter monoterpenes. Functionally, yuzu works in fresh-aromatic and minimalist compositions. It pairs with green tea, hinoki, shiso, and aquatic materials. It bridges citrus and herbal families without the soapy sweetness of linalool-heavy petitgrain oils. Usage is not restricted for phototoxicity — bergapten is undetectable (<0.1 ppm) in cold-pressed yuzu oil — but citral content requires EU allergen declaration above threshold concentrations. No Première Peau fragrance currently features yuzu as a declared ingredient.
