delta-Undecalactone

What delta-Undecalactone smells like

delta-Undecalactone smells creamy and peach-like, with a waxy, fatty quality. The Good Scents Company lists creamy, fatty, coconut, fruity, peach and waxy; a panel adds milky and lactonic with a slight green fruity nuance; Bedoukian peachy, fruity and waxy, for peach, apricot, vanilla and cream notes; Moellhausen creamy, fatty, somewhat fruit-like, peach and coconut. Peach and cream are the most consistent; how much coconut varies by source.

Leading note

Creamy peach

Supporting facets

Coconut, waxy, fatty

Faint facets

Milky, green

Character

Creamy, soft, smooth

• creamy
• coconut
• peach
• milky

What makes delta-Undecalactone distinctive

Between the coconut and the peach: the delta lactone where the fruit starts to show through the cream.

How delta-Undecalactone is used

Used in peach, apricot, vanilla and cream notes, in creamy gourmand and coconut accords, and as a lactonic modifier in white florals.

Typical role: blender (smooths the joins between other materials).

How delta-Undecalactone differs from similar materials

delta-Decalactone

delta-Decalactone is more coconut and milk; delta-undecalactone leans more towards peach.

delta-Dodecalactone

delta-Dodecalactone is heavier and more buttery; the undecalactone is lighter and more peach-like.

Each difference compares the published descriptions of the two materials. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.

Identity and classification

Type

Aroma chemical

Origin

Occurs in nature

Odour family

Gourmand / Fruity

Note position

Heart to base note

Physical form at room temperature

Liquid

Also known as

5-Undecanolide, 6-Hexyltetrahydro-2H-pyran-2-one

CAS number

710-04-3

Molecular formula

C11H20O2

Molecular weight

184.27 g/mol

IUPAC name

6-hexyloxan-2-one

The CAS number, formula and molecular weight are taken from PubChem compound 61204, whose own record lists this CAS number; checked 19 October 2026.

Safety and compliance

Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. Companies notifying the ECHA C&L Inventory report it as not meeting the GHS hazard criteria (1,466 of 1,509 reports). Unless it is harmonised, this is the notifiers' own classification, not a binding one.

This page is general information, not a safety assessment or a specification. Confirm identity, composition, IFRA status and allergen content from your supplier's documents for the lot you hold.

Materials it works with

• delta-Decalactone

  Aroma chemical · Gourmand / Fruity — creamy, milky, coconut, buttery

• delta-Dodecalactone

  Aroma chemical · Gourmand / Fruity — creamy, buttery, coconut, peach

• gamma-Undecalactone (Aldehyde C-14)

  Aroma chemical · Fruity / Gourmand — peach, apricot, creamy, fruity

• Coumarin

  Aroma chemical · Powdery / Fougère — hay, sweet, almond, tobacco

Used in formulas and accords

Used in 2 published formulas

delta-Undecalactone is an ingredient in 2 perfume formulas in the Formula & Accord Library.

RUŌOD House Originals

Original compositions by RUŌOD House.

• Apricot Dust

  RUŌOD House Original

• Orange Soda Sunset

  RUŌOD House Original

Further reading

• Building a Gourmand Accord: Vanilla, Caramel and Beyond

  The materials of gourmand perfume — vanillin, ethyl maltol, coumarin, lactones, roasted notes — how to keep them wearable, and color and crystal problems.

Questions about delta-Undecalactone

Sources

• PubChem — compound 61204, checked 19 October 2026.
• PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
• The Good Scents Company — delta-undecalactone (with Bedoukian and Moellhausen descriptions) — odour database.
• ChemicalBook — delta-undecalactone (CAS 710-04-3) — odour database.
• Parchem — delta undecalactone specification — distributor's description.
• Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 20 October 2026. Evidence: more than one published description. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.