FlavScents AInsights Entry: Buchu Mercaptan (CAS: 38462-22-5)

1. Identity & Chemical Information

• Common Name(s): Buchu Mercaptan
• IUPAC Name: 2-Methyl-2-propanethiol
• CAS Number: 38462-22-5
• FEMA Number: Not available
• Other Identifiers: Not available
• Molecular Formula: C4H10S
• Molecular Weight: 90.19 g/mol

Buchu mercaptan is characterized by its thiol functional group, which is responsible for its potent odor. The presence of the sulfur atom in the thiol group contributes to its distinctive and intense aroma, often described as reminiscent of blackcurrant or cat urine. This compound is a single, discrete chemical entity.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Buchu mercaptan is known for its strong, penetrating odor, often described as blackcurrant-like with sulfurous undertones. It is highly diffusive and can be perceived at very low concentrations. The compound serves as an impact note in flavor and fragrance formulations, providing a unique character that can enhance the perception of fruitiness, particularly in blackcurrant and tropical fruit profiles. The odor threshold is extremely low, making it effective in trace amounts.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Buchu mercaptan is naturally found in the essential oils of certain plants, notably those in the Rutaceae family, such as Agathosma betulina (buchu). It can also form through enzymatic degradation of precursor compounds in these plants. Its presence in natural sources allows it to be used in "natural flavor" designations, provided it is derived from these botanical origins.

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

4. Use in Flavors

Buchu mercaptan is primarily used in fruit flavor formulations, especially those mimicking blackcurrant, passion fruit, and other tropical fruits. It acts as a powerful impact note, enhancing the authenticity and complexity of these flavors. Typical use levels in finished food or beverage products are extremely low, often in the range of 0.01 to 0.1 ppm, due to its intense aroma. It is relatively stable under typical processing conditions but can be sensitive to oxidation, which may alter its sensory profile.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In fragrance applications, buchu mercaptan is used to impart a fresh, fruity note, often in compositions that require a blackcurrant or tropical fruit character. It is typically used in trace amounts due to its high potency. The compound contributes primarily to the top note of a fragrance, given its high volatility. It is used in a variety of product types, including fine fragrances, personal care products, and household items.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Buchu mercaptan does not have a specific FEMA GRAS status but can be used in flavors under general safety guidelines.
• European Union: It is regulated under the EU's flavoring regulations (Reg. (EC) No 1334/2008) but does not have a specific FL number.
• United Kingdom: Post-Brexit, the UK aligns with EU regulations for flavorings.
• Asia: Specific regulatory information for Japan, China, and ASEAN countries is not clearly reported.
• Latin America: Regulatory status in Brazil and MERCOSUR countries is not explicitly documented.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

For oral exposure, buchu mercaptan is used at very low levels, minimizing potential toxicity concerns. No specific ADI or MSDI values are available, but its use is generally considered safe within industry-typical concentrations. Dermal exposure in fragrance applications should consider potential irritation or sensitization, although specific IFRA guidelines are not available. Inhalation exposure is primarily relevant in occupational settings, where adequate ventilation should be ensured due to its volatility.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Buchu mercaptan is valued for its ability to impart a distinctive blackcurrant note, enhancing the realism and complexity of fruit flavors and fragrances. It synergizes well with other fruity and green notes but should be used judiciously to avoid overpowering the formulation. Common pitfalls include overuse, leading to an undesirable sulfurous character. It is often under-utilized in formulations where a subtle fruitiness is desired.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on buchu mercaptan is well-established in terms of its sensory characteristics and typical use levels. However, specific regulatory approvals and toxicological data are less documented, requiring formulators to rely on industry-typical practices and general safety guidelines.

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 2026-01-29 01:56:51 GMT (p2)