FlavScents AInsights Entry for Gamma-Hexalactone (CAS: 695-06-7)

1. Identity & Chemical Information

Gamma-hexalactone, also known as 4-methyl-5-oxo-tetrahydrofuran, is a lactone compound with the CAS number 695-06-7. It is identified by the FEMA number 2544. The molecular formula for gamma-hexalactone is C6H10O2, and it has a molecular weight of 114.14 g/mol. This compound features a lactone ring, which is crucial for its characteristic coconut-like odor. The presence of the lactone functional group is significant in determining its sensory properties, particularly its sweet, creamy aroma.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Gamma-hexalactone is primarily recognized for its creamy, coconut-like odor, which is both sweet and milky. It is often described as having a moderate intensity with good diffusion properties. The compound is used as an impact note in flavor formulations, providing a rich, tropical character. While specific taste and odor thresholds are not widely documented, gamma-hexalactone is typically used in low concentrations due to its potent sensory impact.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Gamma-hexalactone occurs naturally in various fruits and dairy products. It is formed through the enzymatic degradation of fatty acids, a process that can occur during the ripening of fruits or fermentation of dairy. This compound is relevant to the designation of "natural flavor" due to its presence in natural sources and its formation through natural biochemical pathways.

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

4. Use in Flavors

Gamma-hexalactone is widely used in flavor formulations, particularly in tropical and dairy profiles. It is commonly found in coconut, cream, and butter flavors, where it acts as a key impact note. Typical use levels in finished food or beverage products range from 0.5 to 5 ppm, with higher concentrations potentially leading to an overpowering effect. The compound is relatively stable under normal 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, gamma-hexalactone is utilized in various fragrance families, including gourmand and tropical scents. It serves as a modifier, adding creamy and sweet nuances to compositions. Typical concentration ranges in fragrance formulations are from trace amounts up to 0.5%, depending on the desired intensity. Gamma-hexalactone contributes primarily to the middle notes of a fragrance due to its moderate volatility.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

In the United States, gamma-hexalactone 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 an FL number. The United Kingdom follows similar regulations post-Brexit. In Asia, gamma-hexalactone is generally accepted in Japan and China, though specific regulations may vary. In Latin America, countries like Brazil and members of MERCOSUR also permit its use, aligning with international standards.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

Gamma-hexalactone is considered safe for use in food and fragrance applications at typical exposure levels. For oral exposure, it has a high margin of safety, with no adverse effects reported at typical use levels. Dermal exposure in fragrance applications is generally safe, with low potential for irritation or sensitization, as supported by IFRA guidelines. Inhalation exposure is minimal due to its moderate volatility, but occupational exposure should be managed with standard safety practices.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Gamma-hexalactone is valued for its ability to impart a rich, creamy character to both flavors and fragrances. It synergizes well with other lactones and tropical notes, enhancing the overall profile. Formulators should be cautious of its potency, as overuse can lead to an undesirable, overpowering effect. It is often under-utilized in non-tropical applications, where it can add depth and complexity.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on gamma-hexalactone is well-established, with comprehensive sensory and regulatory information available. While industry practices are well-documented, some variability in natural occurrence data exists due to differences in source materials. Overall, the confidence in the data quality is high, with no significant gaps identified.

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 2026-06-25 12:12:50 GMT (p2)