FlavScents AInsights Entry for 4-Methyl Guaiacol (CAS: 93-51-6)

1. Identity & Chemical Information

• Common Name(s): 4-Methyl Guaiacol
• IUPAC Name: 2-Methoxy-4-methylphenol
• CAS Number: 93-51-6
• FEMA Number: 2673
• Other Identifiers: FL No. 02.013
• Molecular Formula: C8H10O2
• Molecular Weight: 138.17 g/mol

4-Methyl guaiacol is a phenolic compound characterized by a methoxy group and a methyl group attached to a benzene ring. Its structure is significant for its odor properties, contributing to its smoky and spicy aroma, which is relevant in both flavor and fragrance applications.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

4-Methyl guaiacol is known for its distinctive smoky, spicy, and clove-like aroma. It is often described as having a warm, woody character with moderate intensity and good diffusion. The compound plays a crucial role as an impact note in flavor systems, providing depth and complexity. While specific taste and odor thresholds are not widely reported, its potent sensory attributes make it effective even at low concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

4-Methyl guaiacol naturally occurs in various smoked foods and is a component of wood smoke. It is also found in roasted coffee, whiskey, and certain types of cheese. The compound can form through the pyrolysis of lignin, a major component of wood, during smoking or roasting processes. Its presence in natural products allows it to be designated as a "natural flavor" under certain regulatory frameworks.

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

4. Use in Flavors

4-Methyl guaiacol is utilized in a variety of flavor categories, including smoked, roasted, and spicy profiles. It serves as an impact note, enhancing the authenticity and depth of flavors in sauces, meats, and beverages. Typical use levels in finished products range from 0.1 to 5 ppm, with higher concentrations potentially leading to overpowering effects. The compound is stable under typical food processing conditions, though it may degrade under extreme heat or prolonged exposure to air.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In fragrance formulations, 4-methyl guaiacol is used to impart a smoky, woody character, often in oriental and woody fragrance families. It functions as a modifier or trace realism note, contributing to the complexity of the scent profile. Typical concentrations range from trace amounts to 0.5% in the final product, depending on the desired intensity. Its volatility allows it to act as a middle note, providing a lasting presence in the fragrance composition.

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 No. 02.013.
• United Kingdom: Aligns with EU regulations post-Brexit.
• Asia: Approved for use in Japan and China, with specific concentration limits.
• Latin America: Generally accepted in Brazil and MERCOSUR countries, subject to local regulations.

Explicit approvals and harmonized assumptions exist, though formulators should verify specific country requirements due to potential variability.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

For oral exposure, 4-methyl guaiacol is considered safe within the established FEMA GRAS limits, with a margin of safety supported by its low toxicity profile. Dermal exposure in fragrance applications is generally safe, though IFRA guidelines should be consulted to avoid sensitization. Inhalation exposure is minimal due to its moderate volatility, but occupational safety measures should be in place during handling to prevent irritation.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

4-Methyl guaiacol is valued for its ability to impart a rich, smoky character to both flavors and fragrances. It synergizes well with other phenolic compounds and can enhance the authenticity of smoked and roasted profiles. Formulators should be cautious of its potency, as overuse can lead to an overpowering effect. It is often under-utilized in complex blends where its subtlety can add depth without dominating the profile.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on 4-methyl guaiacol is well-established, with comprehensive sensory and regulatory information available. While industry practices are generally documented, some regional regulatory nuances may require further verification. Known data gaps are minimal, primarily related to specific sensory thresholds.

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 2026-04-10 08:35:44 GMT (p2)