AInsights Entry for 2-Octen-4-one (CAS: 4643-27-0)

1. Identity & Chemical Information

• Common Name(s): 2-Octen-4-one
• IUPAC Name: (E)-oct-2-en-4-one
• CAS Number: 4643-27-0
• FEMA Number: Not available
• Other Identifiers: FL number not available; CoE number not available; IFRA reference not available
• Molecular Formula: C8H14O
• Molecular Weight: 126.20 g/mol

2-Octen-4-one is a ketone characterized by an unsaturated carbon chain with a double bond and a carbonyl group. The presence of the carbonyl group is significant for its odor properties, contributing to its distinct sensory profile.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

2-Octen-4-one is known for its strong, mushroom-like odor with earthy and green nuances. It is often described as having a moderate to high intensity and is used as an impact note in flavor compositions. The compound's odor threshold is relatively low, making it effective even at minimal concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

2-Octen-4-one is naturally found in various foods, including mushrooms and some types of cheese. It can also form through the oxidation of unsaturated fatty acids, a process that occurs during the storage and processing of food products. This compound is relevant for "natural flavor" designations when derived from natural sources.

Citation hooks: FlavScents; food chemistry literature; EFSA/JECFA monographs

4. Use in Flavors

2-Octen-4-one is utilized in flavor formulations primarily for its mushroom-like and earthy notes. It is commonly used in savory applications, such as soups, sauces, and meat products. Typical use levels in finished food products range from 0.1 to 5 ppm, depending on the desired intensity and the specific application. The compound is relatively stable under typical processing conditions but may degrade under extreme heat or prolonged exposure to air.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, 2-octen-4-one is used to impart earthy and green notes, often in chypre and fougère fragrance families. It serves as a modifier or impact note, contributing to the complexity and depth of the fragrance. Typical concentrations in fragrance formulations are low, often less than 0.1%, due to its potent odor. The compound is volatile and primarily contributes to the top and middle notes of a fragrance.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Not explicitly listed as FEMA GRAS; usage in flavors should comply with general safety standards.
• European Union: Not specifically listed under Regulation (EC) No 1334/2008; use should align with general flavoring guidelines.
• United Kingdom: Follows EU regulations post-Brexit; no specific divergence noted.
• Asia: Limited specific data; general compliance with local flavoring regulations is advised.
• Latin America: No specific data; adherence to MERCOSUR and local regulations is recommended.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

• Oral Exposure: No specific ADI or MSDI established; use should be guided by general safety assessments and industry practices.
• Dermal Exposure: Limited data on irritation or sensitization; IFRA guidelines should be consulted for fragrance use.
• Inhalation Exposure: Volatile nature suggests potential for inhalation exposure; occupational safety measures should be considered in manufacturing settings.

Risk profiles may vary between food and fragrance applications, with dermal and inhalation routes being more relevant for fragrance use.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

2-Octen-4-one is valued for its ability to impart authentic mushroom and earthy notes in both flavors and fragrances. It synergizes well with other green and earthy compounds but can be overpowering if used excessively. Formulators should be cautious of its potent odor and adjust concentrations accordingly to avoid overwhelming the composition.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on 2-octen-4-one is well-established in terms of its sensory characteristics and typical applications. However, specific regulatory approvals and detailed toxicological data are less documented, requiring formulators to rely on general industry practices and safety assessments.

Citation hooks: FlavScents

QA Check

• All required sections 1–9 are present
• "Citation hooks:" line is present under each section
• Flavor section includes ppm ranges
• Toxicology section covers oral, dermal, inhalation
• Regulatory section mentions US, EU, UK, Asia, Latin America
• If complex natural material: includes section 5a (not applicable here)

About FlavScents AInsights (Disclosure)
FlavScents AInsights integrates information from authoritative government, scientific, academic, and industry sources to provide applied, exposure-aware insight into flavor and fragrance materials. Data are drawn from regulatory bodies, expert safety panels, peer-reviewed literature, public chemical databases, and long-standing professional practice within the flavor and fragrance community. Where explicit published values exist, they are reported directly; where gaps remain, AInsights reflects widely accepted industry-typical practice derived from convergent sensory behavior, historical commercial use, regulatory non-objection, and expert consensus. All such information is clearly labeled to distinguish documented data from professional guidance or informed estimation, with the goal of offering transparent, practical, and scientifically responsible context for researchers, formulators, and regulatory specialists. This section is generated using advanced computational language modeling to synthesize and structure information from established scientific and regulatory knowledge bases, with the intent of supporting—not replacing—expert review and judgment.

Generated 2026-08-19 13:37:03 GMT (p2)