FlavScents AInsights Entry: 2-Isobutyl-3-methoxypyrazine (CAS: 24683-00-9)

1. Identity & Chemical Information

• Common Name(s): 2-Isobutyl-3-methoxypyrazine
• IUPAC Name: 2-Isobutyl-3-methoxypyrazine
• CAS Number: 24683-00-9
• FEMA Number: 3152
• Other Identifiers: FL No. 07.008
• Molecular Formula: C9H14N2O
• Molecular Weight: 166.22 g/mol

2-Isobutyl-3-methoxypyrazine is a pyrazine compound characterized by its potent odor profile. The methoxy group attached to the pyrazine ring significantly contributes to its distinctive earthy and green bell pepper-like aroma. This compound is often used in very low concentrations due to its high odor intensity.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

2-Isobutyl-3-methoxypyrazine is renowned for its strong, earthy, and green bell pepper aroma. It is a high-impact odorant with a very low odor threshold, often detectable at concentrations as low as 2 ng/L in water. Its intense aroma makes it a powerful impact note in flavor formulations, where it can add authenticity and complexity to vegetable, herbaceous, and earthy profiles.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

This compound naturally occurs in various plants, including bell peppers, peas, and certain grape varieties. It is biosynthesized in plants through enzymatic pathways involving amino acid precursors. Its presence in grapes is particularly significant in the context of wine production, where it contributes to the varietal character of certain wines, such as Sauvignon Blanc.

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

4. Use in Flavors

2-Isobutyl-3-methoxypyrazine is used in flavor formulations to impart green, earthy, and vegetable notes. It is commonly employed in savory applications, including soups, sauces, and seasonings, as well as in certain alcoholic beverages to enhance complexity. Typical use levels in food range from 0.01 to 0.1 ppm, with higher concentrations potentially leading to overpowering and undesirable effects. The compound is stable under typical processing conditions but can degrade under extreme heat or acidic environments.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In perfumery, 2-isobutyl-3-methoxypyrazine is used to add a green, fresh, and earthy character to fragrance compositions. It is often found in fougère and chypre fragrance families, where it serves as a modifier or impact note. Typical concentrations in fragrances are very low, often below 0.01%, due to its potent aroma. It 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)

• United States: Recognized as GRAS by FEMA for flavor use.
• European Union: Approved under Regulation (EC) No 1334/2008 with FL No. 07.008.
• United Kingdom: Follows EU regulations post-Brexit.
• Asia: Approved for use in Japan and China, with specific restrictions on concentration levels.
• Latin America: Generally accepted in MERCOSUR countries, with adherence to international guidelines.

Explicit approvals exist for flavor use, while fragrance applications are subject to IFRA guidelines. There are no significant regulatory uncertainties reported.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

For oral exposure, 2-isobutyl-3-methoxypyrazine is considered safe at typical use levels, with a high margin of safety due to its low concentration in food products. Dermal exposure in fragrances is generally safe, with no significant irritation or sensitization reported at typical use levels. Inhalation exposure is minimal due to its low volatility and use in trace amounts. Overall, the risk profile is similar for both food and fragrance applications.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

2-Isobutyl-3-methoxypyrazine is valued for its ability to impart a realistic green and earthy note, enhancing the authenticity of vegetable and herbaceous flavors. It synergizes well with other pyrazines and green notes but can easily dominate a formulation if not used judiciously. Formulators should be cautious of its potent aroma and ensure precise dosing to avoid overpowering the desired flavor profile.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on 2-isobutyl-3-methoxypyrazine is well-established, with comprehensive sensory and regulatory information available. Industry practices are well-documented, though specific use levels in formulations may vary. No significant data gaps or regulatory ambiguities are noted.

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 2026-02-19 14:26:18 GMT (p2)