AInsights Entry for (E,E)-2,4-hexadienal (CAS: 142-83-6)

1. Identity & Chemical Information

• Common Name(s): (E,E)-2,4-hexadienal
• IUPAC Name: (2E,4E)-hexa-2,4-dienal
• CAS Number: 142-83-6
• FEMA Number: Not available
• Other Identifiers: FL number not available; CoE number not available; IFRA reference not available
• Molecular Formula: C6H8O
• Molecular Weight: 96.13 g/mol
• Functional Groups and Structure–Odor Relevance: (E,E)-2,4-hexadienal is an α,β-unsaturated aldehyde. The conjugated double bonds contribute to its reactivity and sensory properties, often imparting a green, grassy odor profile.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

• Odor and Flavor Descriptors: (E,E)-2,4-hexadienal is characterized by a strong, green, grassy odor with nuances of cucumber and melon. It is often described as having a fresh, aldehydic quality.
• Taste and/or Odor Thresholds: Specific thresholds are not clearly reported, but it is known to be potent at low concentrations.
• Typical Sensory Role: It serves as an impact note in flavor formulations, providing freshness and green notes to compositions.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

• Known Natural Sources: (E,E)-2,4-hexadienal is found in various fruits and vegetables, including tomatoes and melons. It is also present in some essential oils.
• Formation Pathways: It can form through the enzymatic degradation of polyunsaturated fatty acids, particularly linoleic acid, during the ripening of fruits or through mechanical damage to plant tissues.
• Relevance to “Natural Flavor” or “Natural Fragrance” Designation: Its presence in natural sources allows it to be used in natural flavor formulations, provided it is derived through acceptable processes.

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

4. Use in Flavors

• Flavor Categories and Applications: Commonly used in fruit, vegetable, and green flavor profiles. It is particularly effective in enhancing the freshness of tomato and cucumber flavors.
• Functional Role in Flavor Systems: Acts as an impact note and modifier, adding authenticity and freshness.
• Typical Use Levels: Documented use levels range from 0.1 to 5 ppm in finished food products, with typical levels around 1 ppm.
• Stability Considerations: It is relatively stable under acidic conditions but can degrade under high heat and oxidative conditions.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

• Fragrance Families and Product Types: Utilized in green, fresh, and aldehydic fragrance compositions. Common in personal care products and household cleaners.
• Functional Role: Provides trace realism and acts as a modifier to enhance green notes.
• Typical Concentration Ranges: Typically used at trace levels, often below 0.1% in fragrance formulations.
• Volatility and Top/Middle/Base Contribution: It is a top note due to its high volatility, contributing to the initial impression of freshness.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States (FDA / FEMA GRAS): Not explicitly listed as GRAS by FEMA.
• European Union (Reg. (EC) No 1334/2008; FL number status): Not specifically listed; use may be subject to general flavoring regulations.
• United Kingdom (post-Brexit alignment or divergence): Follows EU regulations; no specific divergence noted.
• Asia (Japan, China, ASEAN): High-level regulatory information not clearly reported; typically follows international guidelines.
• Latin America (e.g., Brazil, MERCOSUR): Regulatory status not explicitly documented; generally aligns with international standards.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

• Oral Exposure: No specific ADI or MSDI values reported; generally considered safe at typical flavor use levels.
• Dermal Exposure: Limited data on irritation or sensitization; IFRA guidelines should be consulted for fragrance use.
• Inhalation Exposure: High volatility suggests potential for inhalation exposure; occupational safety measures should be considered in manufacturing settings.
• Risk Profiles: Generally considered safe for both food and fragrance applications at typical use levels.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

• Why This Material is Valuable: Provides a unique green, fresh note that is difficult to replicate with other materials.
• Typical Synergies: Works well with other aldehydes and green notes to enhance freshness.
• Common Formulation Pitfalls: Overuse can lead to an overpowering or harsh odor; balance is key.
• Situations Where It is Frequently Over- or Under-used: Often under-used in complex formulations where its impact can be masked by other components.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

• Well-Established Data: Sensory characteristics and natural occurrence are well-documented.
• Industry-Typical but Undocumented Practices: Use levels and synergies are often based on industry experience rather than formal studies.
• Known Data Gaps or Regulatory Ambiguities: Specific regulatory approvals and toxicological data are limited.

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 2026-08-21 05:29:28 GMT (p2)