FlavScents AInsights Entry for (E)-2-hexenoic acid (CAS: 13419-69-7)

1. Identity & Chemical Information

• Common Name(s): (E)-2-hexenoic acid
• IUPAC Name: (E)-hex-2-enoic acid
• CAS Number: 13419-69-7
• FEMA Number: Not available
• Other Identifiers: Not available
• Molecular Formula: C6H10O2
• Molecular Weight: 114.14 g/mol

(E)-2-hexenoic acid is an unsaturated carboxylic acid characterized by a double bond in the trans configuration. The presence of the carboxylic acid group contributes to its acidic properties, while the unsaturation influences its reactivity and sensory attributes. The structure-odor relevance is significant as the double bond configuration can affect the material's volatility and sensory perception.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

(E)-2-hexenoic acid is known for its sharp, pungent odor with green and slightly fatty undertones. It is often described as having a sour, vinegary aroma, which can be intense and diffusive. The compound's sensory role is typically as a modifier, providing a tangy, fresh note that can enhance the realism of green or fruity compositions.

Taste and odor thresholds for (E)-2-hexenoic acid are not well-documented, but its potent aroma suggests a low threshold, making it effective even at minimal concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

(E)-2-hexenoic acid is not commonly found in nature but can be formed through the oxidation of hexanal or the enzymatic degradation of fatty acids. It is not typically associated with "natural flavor" or "natural fragrance" designations due to its synthetic origin in most commercial applications.

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

4. Use in Flavors

(E)-2-hexenoic acid is used in flavor formulations to impart a fresh, tangy note, often in fruit and vegetable flavors. It acts as a functional modifier, enhancing the authenticity of green and citrus profiles. Typical use levels in finished food or beverage products range from 0.1 to 5 ppm, with higher concentrations potentially leading to overpowering or off-notes.

Stability considerations include sensitivity to heat and oxidation, which can alter its sensory characteristics. Formulators should ensure proper storage and handling to maintain its integrity.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In fragrance applications, (E)-2-hexenoic acid contributes to green and fresh accords, often used in fine fragrances and personal care products. It serves as a trace realism enhancer or a modifier, with typical concentrations ranging from 0.01% to 0.1% in formulations. Its volatility places it in the top to middle note category, providing an initial burst of freshness.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Not explicitly listed as FEMA GRAS; usage should comply with general safety standards.
• European Union: Not specifically listed under Regulation (EC) No 1334/2008; usage 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 flavor and fragrance 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

For oral exposure, (E)-2-hexenoic acid's safety profile is not well-documented, necessitating cautious use in flavor applications. Dermal exposure in fragrance use should consider potential irritation or sensitization, although specific IFRA guidelines are not available. Inhalation exposure is generally low risk due to its limited volatility, but occupational safety measures should be observed.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

(E)-2-hexenoic acid is valued for its ability to impart a fresh, tangy note, enhancing the realism of green and fruity profiles. It synergizes well with other green and citrus compounds but can be overpowering if overused. Formulators should be mindful of its stability and potential for off-notes at higher concentrations.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

Data on (E)-2-hexenoic acid is limited, with much reliance on industry-typical practices and undocumented insights. Regulatory ambiguities exist, particularly in non-EU regions, necessitating careful compliance verification.

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 2026-09-14 19:32:12 GMT (p2)