AInsights Entry for Isoamyl Alcohol (CAS: 123-51-3)

1. Identity & Chemical Information

Isoamyl alcohol, also known as isopentyl alcohol, is a colorless liquid with a characteristic strong odor. Its IUPAC name is 3-methylbutan-1-ol. The CAS number for isoamyl alcohol is 123-51-3. It is identified by FEMA number 2059. Other identifiers include FL number 02.015 and CoE number 145. The molecular formula is C5H12O, and it has a molecular weight of 88.15 g/mol. Isoamyl alcohol contains a primary alcohol functional group, which contributes to its solubility in water and its characteristic odor profile.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Isoamyl alcohol is known for its strong, pungent odor reminiscent of banana or pear, often described as fruity and sweet. It has a moderate intensity and good diffusion properties. The taste threshold is relatively low, making it a potent impact note in flavor formulations. It is typically used as a background realism enhancer or as a modifier in both flavor and fragrance compositions.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Isoamyl alcohol naturally occurs in various fruits, including bananas and apples, and is a byproduct of fermentation processes. It is formed through the enzymatic degradation of amino acids during fermentation, particularly from leucine. Its presence in natural sources allows it to be designated as a "natural flavor" or "natural fragrance" under certain regulatory frameworks.

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

4. Use in Flavors

Isoamyl alcohol is widely used in flavor formulations, particularly in fruit flavors such as banana, apple, and pear. It serves as an impact note and a background realism enhancer. Typical use levels in finished food or beverages range from 1 to 30 ppm, with higher concentrations used in more robust flavor profiles. It is relatively stable under heat and acidic conditions but can oxidize over time, affecting its sensory properties.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In fragrances, isoamyl alcohol is used across various fragrance families, including fruity and floral compositions. It acts as a modifier and an impact note, contributing to the top and middle notes of a fragrance. Typical concentration ranges are from trace amounts to 1% in finished products, depending on the desired intensity and diffusion. Its volatility makes it suitable for top and middle note applications.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

In the United States, isoamyl alcohol is recognized as GRAS (Generally Recognized As Safe) by FEMA for flavor use. In the European Union, it is listed under Regulation (EC) No 1334/2008 with an assigned FL number. The United Kingdom follows similar regulations post-Brexit. In Asia, it is approved for use in Japan and China, with specific guidelines in ASEAN countries. In Latin America, countries like Brazil and members of MERCOSUR have harmonized regulations allowing its use in flavors and fragrances.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

Isoamyl alcohol is considered safe for oral exposure at typical use levels, with an acceptable daily intake (ADI) established by regulatory bodies. Dermal exposure in fragrance applications is generally safe, though it may cause irritation or sensitization in sensitive individuals. Inhalation exposure is minimal due to its low volatility, but occupational exposure should be monitored to prevent respiratory irritation. The risk profiles for food and fragrance applications are similar, with no significant differences noted.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Isoamyl alcohol is valued for its ability to enhance fruit flavors and add realism to fragrance compositions. It synergizes well with other esters and alcohols, providing a balanced and rounded profile. Formulators should be cautious of its strong odor, which can dominate if overused. It is often under-utilized in complex formulations where subtlety is required.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on isoamyl alcohol is well-established, with comprehensive documentation available from authoritative sources. Industry practices are well-documented, though some variability exists in use levels and sensory descriptions. Known data gaps are minimal, with regulatory frameworks providing clear guidance on 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

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 2026-09-10 20:44:05 GMT (p2)