FlavScents AInsights Entry for Acetal (CAS: 105-57-7)

1. Identity & Chemical Information

• Common Name(s): Acetal, 1,1-Diethoxyethane
• IUPAC Name: 1,1-Diethoxyethane
• CAS Number: 105-57-7
• FEMA Number: 2003
• Other Identifiers: FL No. 02.001
• Molecular Formula: C6H14O2
• Molecular Weight: 118.18 g/mol

Acetal is a simple aliphatic compound characterized by its two ethoxy groups attached to a central carbon. This structure contributes to its fruity, ethereal odor, which is often associated with green apple or pear notes. The presence of the ether functional group is crucial for its volatility and odor profile, making it a valuable component in both flavor and fragrance formulations.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Acetal is known for its distinctive fruity aroma, often described as reminiscent of green apples or pears. It exhibits a moderate intensity and is typically used as an impact note in flavor compositions. The compound's odor threshold is relatively low, allowing it to impart a noticeable effect even at minimal concentrations. In flavor systems, acetal is valued for its ability to enhance the freshness and juiciness of fruit profiles, acting as a modifier to add realism and complexity.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Acetal is not commonly found in nature but can be formed through the acid-catalyzed reaction of ethanol with acetaldehyde. This reaction pathway is relevant in the context of alcoholic beverages and fermented products, where acetal may be present as a byproduct. Its formation through natural fermentation processes allows it to be designated as a "natural flavor" under certain regulatory frameworks, provided it is derived from natural sources.

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

4. Use in Flavors

Acetal is primarily used in fruit flavor formulations, particularly those mimicking apple, pear, and other green fruits. It serves as an impact note, providing a fresh, juicy character that enhances the overall flavor profile. Typical use levels in finished food or beverage products range from 1 to 10 ppm, with higher concentrations potentially leading to an overpowering effect. Acetal is relatively stable under acidic conditions but may degrade under high heat or oxidative environments, necessitating careful formulation considerations.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, acetal is utilized for its fresh, fruity aroma, fitting well within the fruity and floral fragrance families. It acts as a modifier, adding a crisp, green note that enhances the realism of fruit and floral compositions. Typical concentration ranges in fragrance products are from 0.1% to 1%, depending on the desired intensity and product type. Acetal's volatility makes it 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: Acetal is approved for use as a flavoring agent under FEMA GRAS status.
• European Union: Listed under Regulation (EC) No 1334/2008 with FL No. 02.001, allowing its use in food flavorings.
• United Kingdom: Post-Brexit regulations align with EU standards, maintaining its approved status.
• Asia: In Japan and China, acetal is permitted for use in flavors, subject to specific concentration limits.
• Latin America: Recognized under MERCOSUR regulations, with usage aligned to international standards.

Explicit approvals and harmonized assumptions are generally consistent across regions, though formulators should verify specific country regulations for any updates or variations.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

Acetal is considered safe for use in food and fragrance applications at typical exposure levels.

• Oral Exposure: The compound has a high margin of safety when used within recommended ppm levels in food products. No specific ADI or MSDI values are established, but its FEMA GRAS status supports its safety.
• Dermal Exposure: In fragrance applications, acetal is not known to cause irritation or sensitization at typical use levels. IFRA guidelines do not list specific restrictions for acetal.
• Inhalation Exposure: Given its volatility, inhalation exposure is possible, but occupational exposure limits are not typically exceeded in standard use scenarios.

Overall, the risk profiles for food and fragrance applications are similar, with no significant safety concerns identified at standard usage levels.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Acetal is valued for its ability to impart a fresh, fruity character to both flavors and fragrances. It synergizes well with other fruity and floral notes, enhancing the overall complexity and realism of formulations. Common pitfalls include overuse, which can lead to an artificial or overpowering effect. Formulators should balance acetal with other components to achieve the desired sensory profile without overwhelming the composition.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on acetal is well-established, with comprehensive documentation available from authoritative sources such as FEMA and EFSA. Industry practices are consistent with documented guidelines, though specific ppm ranges may vary based on formulation goals. No significant data gaps or regulatory ambiguities are noted, providing a high level of confidence in the material's safety and efficacy.

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 2026-01-21 13:32:01 GMT (p2)