FlavScents AInsights Entry for 4-Ethyl Guaiacol (CAS: 2785-89-9)

1. Identity & Chemical Information

• Common Name(s): 4-Ethyl Guaiacol
• IUPAC Name: 2-Methoxy-4-ethylphenol
• CAS Number: 2785-89-9
• FEMA Number: 3177
• Other Identifiers: FL No. 02.013
• Molecular Formula: C9H12O2
• Molecular Weight: 152.19 g/mol

4-Ethyl guaiacol is a phenolic compound characterized by the presence of an ethyl group and a methoxy group attached to a benzene ring. The functional groups contribute to its distinctive smoky, spicy aroma, which is significant in both flavor and fragrance applications.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

4-Ethyl guaiacol is known for its smoky, spicy, and clove-like aroma, often described as having a sweet, phenolic character. It is a potent odorant with a low detection threshold, contributing significantly to the sensory profile of products even at low concentrations. Its intensity and diffusion make it an impactful note in both flavor and fragrance formulations, often used to impart a smoky or roasted character.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

4-Ethyl guaiacol naturally occurs in various foods and beverages, particularly those that undergo fermentation or roasting processes, such as wine, whiskey, and coffee. It is formed through the degradation of lignin, a complex organic polymer found in plant cell walls, during thermal processing or microbial fermentation. This compound is often associated with the "natural flavor" designation due to its presence in naturally processed foods.

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

4. Use in Flavors

4-Ethyl guaiacol is utilized in flavor formulations to impart smoky, spicy, and clove-like notes. It is commonly used in savory applications, such as barbecue sauces, smoked meats, and certain alcoholic beverages like whiskey and wine. Typical use levels in finished products range from 0.1 to 5 ppm, depending on the desired intensity and product type. It is relatively stable under heat and acidic conditions, making it suitable for various culinary applications.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, 4-ethyl guaiacol is used to add depth and complexity to compositions, often as a trace realism or modifier note. It is found in fragrance families such as woody, spicy, and oriental. Typical concentration ranges in formulations are from trace amounts up to 0.5%, depending on the desired effect. Its volatility allows it to contribute to both the middle and base notes of a fragrance.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Recognized as GRAS by FEMA for flavor use.
• European Union: Approved under Regulation (EC) No 1334/2008 with FL number 02.013.
• United Kingdom: Aligns with EU regulations post-Brexit.
• Asia: Approved for use in Japan and China, with specific restrictions in some ASEAN countries.
• Latin America: Generally accepted, with specific regulations in Brazil and MERCOSUR countries.

Explicit approvals and harmonized assumptions are common, though some country-specific variability exists.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

• Oral Exposure: Considered safe for use in food at typical concentrations, with a high margin of safety.
• Dermal Exposure: Generally non-irritating and non-sensitizing at typical fragrance concentrations; IFRA guidelines should be consulted.
• Inhalation Exposure: Low volatility reduces inhalation risk, though occupational exposure should be monitored in manufacturing settings.

Risk profiles are similar for food and fragrance applications, with no significant differences noted.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

4-Ethyl guaiacol is valued for its ability to impart a smoky, spicy character to both flavors and fragrances. It synergizes well with other phenolic compounds and can enhance the complexity of a formulation. Common pitfalls include overuse, which can lead to an overpowering or artificial taste or scent. It is often under-used in applications where a subtle smoky note could enhance the overall profile.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on 4-ethyl guaiacol is well-established, with comprehensive sensory and regulatory information available. Industry practices are well-documented, though some variability in natural occurrence data exists due to differences in processing methods.

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 2026-03-04 15:10:41 GMT (p2)