FlavScents AInsights Entry for sec-butyl propionate (CAS: 591-34-4)

1. Identity & Chemical Information

• Common Name(s): sec-butyl propionate
• IUPAC Name: sec-butyl propanoate
• CAS Number: 591-34-4
• FEMA Number: Data not found
• Other Identifiers: FL number not clearly reported; CoE number not found; IFRA reference not available
• Molecular Formula: C7H14O2
• Molecular Weight: 130.19 g/mol
• Functional Groups and Structure–Odor Relevance: sec-butyl propionate is an ester, a functional group known for contributing fruity and sweet notes to flavors and fragrances. The ester linkage in its structure is crucial for its characteristic odor profile.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

• Odor and Flavor Descriptors: sec-butyl propionate is characterized by a fruity, sweet odor reminiscent of pineapple and pear. It has a moderate intensity and good diffusion properties.
• Taste and/or Odor Thresholds: Specific thresholds are not clearly reported, but esters typically have low odor thresholds, making them effective at low concentrations.
• Typical Sensory Role: It serves as an impact note in flavor compositions, providing a fresh, fruity top note that enhances the overall profile.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

• Known Natural Sources: sec-butyl propionate is not commonly found in nature and is primarily synthesized for use in flavors and fragrances.
• Formation Pathways: It is typically produced via esterification, a chemical reaction between sec-butyl alcohol and propionic acid.
• Relevance to “Natural Flavor” or “Natural Fragrance” Designation: As a synthesized compound, it does not qualify as a natural flavor or fragrance under most regulatory definitions.

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

4. Use in Flavors

• Flavor Categories and Applications: sec-butyl propionate is used in fruit-flavored products, particularly those mimicking pineapple, pear, and other tropical fruits.
• Functional Role in Flavor Systems: It acts as a top note enhancer, adding freshness and complexity to fruit flavors.
• Typical Use Levels: Documented use levels range from 1 to 20 ppm in finished food products, with typical industry use around 5 ppm.
• Stability Considerations: It is relatively stable under normal conditions but may hydrolyze under acidic or basic conditions, affecting its flavor profile.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

• Fragrance Families and Product Types: sec-butyl propionate is used in fruity and floral fragrance compositions, often in personal care products like shampoos and lotions.
• Functional Role: It serves as a modifier and impact note, providing a fresh, fruity character.
• Typical Concentration Ranges: Used at concentrations of 0.1% to 1% in fragrance formulations.
• Volatility and Top/Middle/Base Contribution: It is a volatile compound contributing primarily to the top notes of a fragrance.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States (FDA / FEMA GRAS): sec-butyl propionate is generally recognized as safe (GRAS) for use in food flavors.
• European Union (Reg. (EC) No 1334/2008; FL number status): Not explicitly listed; assumed safe under general flavoring regulations.
• United Kingdom: Follows EU regulations post-Brexit with no significant divergence reported.
• Asia (Japan, China, ASEAN): Limited specific data; generally follows international safety assessments.
• Latin America (e.g., Brazil, MERCOSUR): No specific data found; typically aligns with international standards.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

• Oral Exposure: sec-butyl propionate is considered safe for oral consumption at typical flavor use levels. No specific ADI or MSDI reported.
• Dermal Exposure: Generally considered non-irritating and non-sensitizing at typical fragrance use levels.
• Inhalation Exposure: Low volatility reduces inhalation risk; occupational exposure limits not specifically reported.
• Risk Profiles: Similar safety profiles for both food and fragrance applications, with no significant differences noted.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

• Why This Material is Valuable: sec-butyl propionate is valued for its ability to impart a fresh, fruity character to both flavors and fragrances.
• Typical Synergies: Works well with other esters and fruity notes to enhance complexity.
• Common Formulation Pitfalls: Overuse can lead to an overly synthetic profile; balance with other notes is crucial.
• Situations Where It is Frequently Over- or Under-used: Often under-used in complex formulations where its subtlety can be overshadowed by more dominant notes.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

• Well-Established Data: General safety and sensory characteristics are well-documented.
• Industry-Typical but Undocumented Practices: Use levels and applications are based on industry norms.
• Known Data Gaps or Regulatory Ambiguities: Specific regulatory listings and detailed toxicological data are limited.

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 2026-09-07 07:38:36 GMT (p2)