FlavScents AInsights Entry: Hexanal (Aldehyde C-6)
1. Identity & Chemical Information
- Common Name(s): Hexanal, Aldehyde C-6
- IUPAC Name: Hexanal
- CAS Number: 66-25-1
- FEMA Number: 2559
- Other Identifiers: FL No. 02.015
- Molecular Formula: C6H12O
- Molecular Weight: 100.16 g/mol
Hexanal is a saturated aliphatic aldehyde characterized by a six-carbon chain with a terminal aldehyde group. Its structure contributes to its distinctive grassy and green odor, which is a key component in many natural flavors and fragrances. The aldehyde functional group is crucial for its reactivity and sensory properties.
Citation hooks: FlavScents; PubChem; FEMA
2. Sensory Profile
Hexanal is known for its strong, penetrating odor reminiscent of freshly cut grass, green leaves, and unripe fruit. It is often described as having a green, aldehydic, and slightly fatty character. The intensity of hexanal's odor is high, making it an impactful note in both flavor and fragrance compositions. Its odor threshold is relatively low, allowing it to be perceived at minimal concentrations, which makes it effective as an impact note or modifier in formulations.
Citation hooks: FlavScents; peer-reviewed sensory literature
3. Natural Occurrence & Formation
Hexanal is naturally found in a variety of plants and fruits, including apples, bananas, and citrus fruits. It is also present in essential oils such as eucalyptus and peppermint. Hexanal is commonly formed through the oxidative degradation of unsaturated fatty acids, particularly linoleic acid, during processes like lipid peroxidation. This pathway is significant in the context of food spoilage and the development of off-flavors. Its presence in natural sources supports its designation as a "natural flavor" or "natural fragrance" component.
Citation hooks: FlavScents; food chemistry literature; EFSA/JECFA monographs
4. Use in Flavors
Hexanal is widely used in flavor formulations to impart fresh, green, and fruity notes. It is commonly employed in fruit flavors, particularly apple and citrus, as well as in vegetable and herbal profiles. Hexanal serves as an impact note, providing realism and freshness to flavor systems. Typical use levels in finished food products range from 0.1 to 5 ppm, with variations depending on the desired intensity and product type. Hexanal is relatively stable under acidic conditions but can degrade under high heat or oxidative environments, which formulators must consider during product development.
Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature
5. Use in Fragrances
In the fragrance industry, hexanal is valued for its ability to impart fresh, green, and aldehydic notes. It is used in a variety of fragrance families, including green, floral, and citrus compositions. Hexanal acts as a top note due to its high volatility, contributing to the initial impression of freshness and naturalness. Typical concentrations in fragrance formulations range from trace amounts to 0.5%, depending on the desired effect and product type.
Citation hooks: FlavScents; IFRA; fragrance chemistry texts
6. Regulatory Status (Regional Overview)
United States
Hexanal is approved for use as a flavoring agent under FEMA GRAS status. It is also recognized by the FDA as a safe substance when used in accordance with good manufacturing practices.
European Union
Hexanal is listed under Regulation (EC) No 1334/2008 with an assigned FL number, indicating its approval for use in flavorings.
United Kingdom
Post-Brexit, the UK aligns with EU regulations regarding flavoring substances, maintaining similar approval status for hexanal.
Asia
In Japan, hexanal is permitted for use in food flavorings. Regulatory details for China and ASEAN countries are less explicit but generally align with international standards.
Latin America
Countries like Brazil and those in MERCOSUR follow similar guidelines to the US and EU, allowing hexanal in food and fragrance applications.
Citation hooks: FEMA; EFSA; national authority publications
7. Toxicology, Safety & Exposure Considerations
Oral Exposure
Hexanal is considered safe for oral consumption at typical flavoring levels, with an acceptable daily intake (ADI) not specifically established but implied under GRAS status.
Dermal Exposure
In fragrance applications, hexanal is generally non-irritating at typical use levels. However, it can cause sensitization in some individuals, necessitating adherence to IFRA guidelines.
Inhalation Exposure
Due to its volatility, hexanal can be inhaled, but it is not associated with significant respiratory risks at typical exposure levels in consumer products.
Overall, hexanal's risk profile is similar across food and fragrance applications, with safety ensured through adherence to regulatory guidelines and industry best practices.
Citation hooks: EFSA; FEMA; PubChem; toxicology literature
8. Practical Insights for Formulators
Hexanal is a valuable ingredient for its ability to impart fresh, green notes that enhance the realism of both flavors and fragrances. It synergizes well with other aldehydes and green notes, providing a crisp, natural character. Formulators should be cautious of its high volatility and potential for oxidation, which can lead to off-notes. It is often under-used in complex formulations where its impact can be overshadowed by more dominant ingredients.
Citation hooks: FlavScents; industry practice
9. Confidence & Data Quality Notes
The data on hexanal is well-established, with comprehensive sensory and regulatory information available. Industry practices are well-documented, though some regional regulatory details may lack specificity. Overall, hexanal is a well-understood compound with reliable data supporting its use.
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 2026-03-04 15:56:58 GMT (p2)
