FlavScents AInsights Entry for 2-Methyl Butyric Acid (CAS: 116-53-0)

1. Identity & Chemical Information

2-Methyl butyric acid, also known as isovaleric acid, is a carboxylic acid with the IUPAC name 2-methylbutanoic acid. It is identified by the CAS number 116-53-0. The FEMA number for this compound is 2693. Other identifiers include the FL number 08.005 and CoE number 186. The molecular formula is C5H10O2, and it has a molecular weight of 102.13 g/mol. The structure of 2-methyl butyric acid includes a carboxyl group, which is crucial for its acidic properties and contributes to its characteristic odor profile.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

2-Methyl butyric acid is characterized by a strong, pungent odor often described as cheesy, sweaty, or rancid. It has a sour, acidic taste with a low odor threshold, making it a potent impact note in formulations. Despite its intense aroma, it is used in small quantities to add complexity and authenticity to flavor profiles, often serving as a background realism enhancer in cheese and dairy flavors.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

This compound naturally occurs in various foods, including cheese, beer, and soy sauce, often as a result of fermentation processes. It can also be formed through the enzymatic degradation of leucine, an amino acid, in biological systems. Its presence in natural products 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

2-Methyl butyric acid is commonly used in flavor formulations for dairy products, especially cheese, where it enhances the authenticity of the flavor profile. It is also used in fruit flavors to add depth and complexity. Typical use levels in finished food products range from 0.1 to 5 ppm, depending on the desired intensity and the specific application. It is relatively stable under acidic conditions but can degrade under high heat or oxidative environments.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, 2-methyl butyric acid is used in trace amounts to add a naturalistic touch to compositions, particularly in recreating the scent of aged cheese or fermented products. It is typically found in the base notes due to its low volatility. Concentration ranges are generally qualitative, as its potent odor requires careful balancing within formulations.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

In the United States, 2-methyl butyric acid is recognized as GRAS (Generally Recognized As Safe) by FEMA for flavor use. In the European Union, it is approved under Regulation (EC) No 1334/2008 and assigned the FL number 08.005. The United Kingdom follows similar regulations post-Brexit. In Asia, it is approved for use in Japan and China, though specific limits may vary. In Latin America, it is generally accepted, but formulators should verify country-specific regulations.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

For oral exposure, 2-methyl butyric acid is considered safe at typical use levels in food, with an acceptable daily intake (ADI) not specifically established but implied through GRAS status. Dermal exposure in fragrances is limited due to potential irritation and sensitization, with IFRA providing guidelines for safe use. Inhalation exposure is generally low risk due to its low volatility, but occupational exposure should be minimized through proper ventilation.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

2-Methyl butyric acid is valued for its ability to impart authenticity and complexity to flavor profiles, particularly in dairy and fruit applications. It synergizes well with other fatty acids and esters. Formulators should be cautious of its potent odor, which can easily overpower a blend if used excessively. It is often under-used due to its intense aroma, but when balanced correctly, it can significantly enhance product realism.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on 2-methyl butyric acid is well-established, with comprehensive sensory and regulatory information available. Industry practices are well-documented, though specific use levels may vary by application. Some regulatory ambiguities exist in less-regulated markets, necessitating careful verification by formulators.

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 2026-07-09 18:15:05 GMT (p2)