FlavScents AInsights Entry for 3-butylidene phthalide (CAS: 551-08-6)

1. Identity & Chemical Information

3-butylidene phthalide is a chemical compound known for its distinctive aroma and flavor characteristics. The IUPAC name for this compound is 3-butylidene-1(3H)-isobenzofuranone. It is registered under the CAS number 551-08-6. While a specific FEMA number is not available, it is recognized in various chemical databases. The molecular formula of 3-butylidene phthalide is C12H12O2, and it has a molecular weight of 188.22 g/mol. This compound features a lactone functional group, which is crucial for its odor profile, contributing to its sweet, spicy, and celery-like aroma.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

3-butylidene phthalide is characterized by its sweet, spicy, and celery-like odor, which is both intense and diffusive. It is often described as having a green, herbal note with a hint of earthiness. The compound is used as an impact note in flavor formulations, providing a distinct celery-like character that enhances the overall sensory experience. While specific taste and odor thresholds are not well-documented, its potent aroma suggests it is effective at low concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

This compound is naturally found in various plants, including celery and lovage, contributing to their characteristic aromas. It is formed through the biosynthesis of phthalides in these plants, often as a result of enzymatic processes. The presence of 3-butylidene phthalide in natural sources supports its designation as a "natural flavor" or "natural fragrance" in regulatory contexts.

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

4. Use in Flavors

3-butylidene phthalide is primarily used in savory flavor applications, such as soups, sauces, and seasonings, where it imparts a celery-like note. It serves as a functional impact note, enhancing the authenticity and complexity of flavor profiles. Typical use levels in finished food products range from 0.1 to 5 ppm, depending on the desired intensity and the specific application. The compound is relatively stable under typical processing conditions, although it may degrade at high temperatures or extreme pH levels.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, 3-butylidene phthalide is used in various fragrance families, including green and herbal compositions. It acts as a modifier or impact note, providing a fresh, natural aroma that enhances the overall fragrance profile. Typical concentration ranges in fragrance formulations are from trace amounts to 0.5%, depending on the desired effect. The compound contributes primarily to the top and middle notes due to its moderate volatility.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

In the United States, 3-butylidene phthalide is generally recognized as safe (GRAS) for use in flavors, although specific FEMA GRAS status may not be available. In the European Union, it is subject to regulation under Regulation (EC) No 1334/2008, with its use in flavors being permitted. Post-Brexit, the United Kingdom aligns with EU regulations, maintaining similar standards. In Asia, including Japan and China, and in Latin America, such as Brazil and MERCOSUR, the compound is typically accepted for use in flavors and fragrances, although specific approvals may vary.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

For oral exposure, 3-butylidene phthalide is considered safe at typical use levels in food, with no specific ADI or MSDI established. Dermal exposure in fragrance applications is generally safe, with no significant irritation or sensitization reported, aligning with IFRA guidelines. Inhalation exposure is considered low risk due to its moderate volatility and typical use concentrations. Overall, the risk profiles for food and fragrance applications are similar, with no significant safety concerns identified.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

3-butylidene phthalide is valued for its ability to impart a natural, celery-like aroma in both flavor and fragrance formulations. It synergizes well with other green and herbal notes, enhancing the overall complexity and authenticity of the product. Formulators should be cautious of overuse, as its potent aroma can dominate other components. It is often under-utilized in fragrance applications, where its unique profile can add freshness and depth.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on 3-butylidene phthalide is well-established, particularly regarding its sensory characteristics and natural occurrence. Industry practices are well-documented, although specific regulatory approvals and safety data may have gaps. Overall, the compound is well-understood, with consistent use in both flavor and fragrance industries.

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 2026-06-02 21:29:32 GMT (p2)