FlavScents AInsights Entry for Rhubarb Oxirane (CAS: 41816-03-9)

1. Identity & Chemical Information

• Common Name(s): Rhubarb oxirane
• IUPAC Name: 2-(3,4-dimethylphenyl)oxirane
• CAS Number: 41816-03-9
• FEMA Number: Not available
• Other Identifiers: Not available
• Molecular Formula: C10H12O
• Molecular Weight: 148.20 g/mol

Rhubarb oxirane is a single chemical compound characterized by an oxirane (epoxide) functional group attached to a dimethylphenyl ring. The presence of the oxirane group is significant for its reactivity and potential odor characteristics, contributing to its sensory profile.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Rhubarb oxirane is noted for its distinctive odor profile, which can be described as fresh, green, and slightly fruity with a rhubarb-like nuance. The intensity of its aroma is moderate, making it suitable for use as a character impact note in both flavors and fragrances. The compound's diffusion is relatively quick, contributing to its role as a top note in formulations.

Taste and odor thresholds for rhubarb oxirane are not clearly reported in the literature, but its sensory role is typically as a modifier or enhancer, adding complexity and freshness to compositions.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Rhubarb oxirane is not known to occur naturally and is typically synthesized for use in flavor and fragrance applications. Its formation involves chemical synthesis pathways that include the epoxidation of dimethylphenyl precursors. Due to its synthetic origin, rhubarb oxirane does not qualify for "natural flavor" or "natural fragrance" designations under most regulatory frameworks.

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

4. Use in Flavors

Rhubarb oxirane is used in a variety of flavor categories, including fruit, vegetable, and herbal profiles. It serves as a functional modifier, enhancing the freshness and complexity of flavor systems. Typical use levels in finished food or beverage products range from 0.5 to 5 ppm, with higher concentrations potentially leading to overpowering effects.

Stability considerations include moderate resistance to heat and pH variations, although it may be susceptible to oxidation, necessitating careful formulation and storage conditions.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In fragrance applications, rhubarb oxirane is valued for its fresh, green, and slightly fruity aroma, fitting well within floral, green, and fruity fragrance families. It is often used as a top note, providing an initial burst of freshness. Typical concentration ranges in fragrance formulations are from 0.1% to 1%, depending on the desired intensity and product type.

The compound's volatility supports its role as a top note, contributing to the initial impression of a fragrance.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Rhubarb oxirane does not have a specific FEMA GRAS status and should be used in compliance with general safety guidelines.
• European Union: Not explicitly listed under Regulation (EC) No 1334/2008; usage should align with general safety and labeling requirements.
• United Kingdom: Post-Brexit regulations align closely with EU standards; no specific divergence noted.
• Asia: Limited specific data; usage should comply with national safety standards.
• Latin America: No specific regulatory data available; general safety compliance is advised.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

• Oral Exposure: No specific ADI or MSDI values are available; formulators should adhere to industry-typical safety margins.
• Dermal Exposure: Limited data on irritation or sensitization; IFRA guidelines should be consulted for fragrance use.
• Inhalation Exposure: Volatility suggests potential for inhalation exposure; occupational safety measures should be considered.

Risk profiles may differ between food and fragrance applications, with fragrance use requiring additional dermal and inhalation safety assessments.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Rhubarb oxirane is valued for its ability to impart a fresh, green character to both flavors and fragrances. It synergizes well with other green and fruity notes, enhancing overall complexity. Common formulation pitfalls include overuse, leading to an overpowering effect, and underuse, resulting in a lack of desired freshness.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

Data on rhubarb oxirane is well-established in terms of its chemical identity and sensory profile. However, there are gaps in specific regulatory approvals and detailed toxicological data. Industry practices often rely on general safety guidelines and empirical formulation experience.

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 2026-07-13 16:06:41 GMT (p2)