FlavScents AInsights Entry for Butyl Butyrate (CAS: 109-21-7)

1. Identity & Chemical Information

• Common Name(s): Butyl Butyrate
• IUPAC Name: Butyl butanoate
• CAS Number: 109-21-7
• FEMA Number: 2203
• Other Identifiers: FL No. 09.010
• Molecular Formula: C8H16O2
• Molecular Weight: 144.21 g/mol

Butyl butyrate is an ester formed from butyric acid and butanol. It is characterized by its fruity odor, which is a result of its ester functional group. This compound is often used in flavor and fragrance formulations due to its pleasant aroma reminiscent of pineapple and apple.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Butyl butyrate is known for its sweet, fruity odor with notes of pineapple and apple. It is often described as having a medium intensity and good diffusion, making it suitable for use as an impact note in both flavors and fragrances. The taste threshold for butyl butyrate is relatively low, allowing it to impart a noticeable flavor even at low concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Butyl butyrate occurs naturally in various fruits, including apples, bananas, and strawberries. It is formed through esterification, a reaction between butyric acid and butanol, which can occur naturally in fruits or be synthesized for industrial use. Its presence in natural sources allows it to be designated as a "natural flavor" in certain regulatory contexts.

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

4. Use in Flavors

Butyl butyrate is widely used in the flavor industry, particularly in fruit-flavored products such as candies, beverages, and baked goods. It serves as a key impact note, providing a sweet, fruity character. Typical use levels in finished products range from 1 to 50 ppm, with higher concentrations used in more intense flavor profiles. It is generally stable under typical processing conditions but may degrade under extreme heat or acidic conditions.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, butyl butyrate is used in various product types, including perfumes, air fresheners, and personal care products. It contributes to fruity and tropical fragrance families, often serving as a top note due to its volatility. Typical concentrations in fragrance formulations range from 0.1% to 1%, depending on the desired intensity and product type.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Butyl butyrate is approved for use as a flavoring agent under FEMA GRAS status.
• European Union: It is listed under Regulation (EC) No 1334/2008 with an assigned FL number, indicating its approval for use in food.
• United Kingdom: Post-Brexit, the regulatory status aligns with the EU, maintaining its approval for use.
• Asia: In Japan and China, butyl butyrate is permitted for use in food and fragrances, subject to local regulations.
• Latin America: Countries like Brazil and members of MERCOSUR recognize butyl butyrate as a safe flavoring agent.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

For oral exposure, butyl butyrate is considered safe at typical use levels, with an acceptable daily intake (ADI) established by regulatory bodies. Dermal exposure in fragrance applications shows low irritation potential, but formulators should adhere to IFRA guidelines to prevent sensitization. Inhalation exposure is generally low risk due to its volatility, but occupational safety measures should be in place to minimize prolonged exposure.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Butyl butyrate is valued for its ability to impart a fresh, fruity note to both flavors and fragrances. It synergizes well with other esters and fruity compounds, enhancing the overall profile. Formulators should be cautious of its volatility and potential for degradation under extreme conditions. It is often under-used in complex formulations where its impact could be beneficial.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on butyl butyrate is well-established, with comprehensive documentation available from authoritative sources. While industry practices are generally consistent, some undocumented uses may exist. Regulatory ambiguities are minimal, with clear guidelines provided by major regulatory bodies.

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 2026-01-20 08:26:10 GMT (p2)