FlavScents AInsights Entry for Isobutyraldehyde (CAS: 78-84-2)

1. Identity & Chemical Information

• Common Name(s): Isobutyraldehyde
• IUPAC Name: 2-Methylpropanal
• CAS Number: 78-84-2
• FEMA Number: 2173
• Other Identifiers: FL No. 02.015
• Molecular Formula: C4H8O
• Molecular Weight: 72.11 g/mol
• Functional Groups and Structure–Odor Relevance: Isobutyraldehyde is an aliphatic aldehyde with a branched structure. The presence of the aldehyde group contributes to its characteristic pungent, fruity odor, which is significant in both flavor and fragrance applications.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Isobutyraldehyde is characterized by a sharp, pungent odor with fruity and nutty undertones. It is often described as having a green, apple-like scent, which can be quite intense and diffusive. In flavor applications, it is used to impart a fresh, fruity note, often enhancing the realism of apple and other fruit flavors. The odor threshold is relatively low, making it effective even at minimal concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Isobutyraldehyde occurs naturally in various fruits and is a byproduct of fermentation processes. It can be formed through the oxidative degradation of isobutanol or via the Maillard reaction during food processing. Its presence in natural sources allows it to be designated as a "natural flavor" under certain regulatory frameworks.

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

4. Use in Flavors

Isobutyraldehyde is utilized in a variety of flavor categories, including fruit, nut, and dairy flavors. It serves as an impact note, providing a fresh, fruity character that enhances the authenticity of apple and other fruit flavors. Typical use levels in finished food or beverages range from 0.1 to 5 ppm, with higher concentrations potentially leading to overpowering notes. It is relatively stable under normal processing conditions but may degrade under extreme heat or acidic conditions.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In fragrance formulations, isobutyraldehyde is used across several fragrance families, including fruity, green, and floral compositions. It acts as a modifier or impact note, contributing to the top notes of a fragrance due to its high volatility. Typical concentrations range from trace amounts to 0.5%, depending on the desired intensity and character of the fragrance.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Recognized as GRAS by FEMA for flavor use.
• European Union: Approved under Regulation (EC) No 1334/2008 with FL No. 02.015.
• United Kingdom: Follows EU regulations post-Brexit with no significant divergence reported.
• Asia: Approved for use in Japan and China, with specific concentration limits varying by country.
• Latin America: Generally accepted in Brazil and MERCOSUR countries, though specific regulations may vary.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

For oral exposure, isobutyraldehyde is considered safe at typical flavor use levels, with an established ADI not clearly reported but generally recognized as safe under FEMA GRAS. Dermal exposure in fragrance applications is limited by IFRA standards to prevent irritation and sensitization. Inhalation exposure is primarily a concern in occupational settings, where adequate ventilation and protective measures are recommended to minimize risk.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Isobutyraldehyde is valued for its ability to impart a fresh, fruity note that enhances the authenticity of fruit flavors and fragrances. It synergizes well with other aldehydes and esters, but care must be taken to avoid overuse, which can lead to an overpowering or harsh character. It is often under-utilized in complex formulations where its impact can be subtly integrated.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on isobutyraldehyde is well-established, with comprehensive sensory and regulatory information available. Industry practices are well-documented, though specific numeric safety thresholds are not always explicitly reported. Known data gaps include detailed toxicological profiles for non-oral exposure routes.

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 2026-07-13 22:01:19 GMT (p2)