FlavScents AInsights Entry for Alpha-Ionone (CAS: 127-41-3)

1. Identity & Chemical Information

Alpha-ionone is a key compound in the realm of flavor and fragrance chemistry. Its IUPAC name is (3E)-3,5,5-trimethylcyclohex-3-en-1-one. The CAS number for alpha-ionone is 127-41-3, and it is recognized by FEMA with the number 2593. Other identifiers include its FL number 07.008 and CoE number 146. The molecular formula of alpha-ionone is C13H20O, with a molecular weight of 192.3 g/mol. Structurally, alpha-ionone is characterized by a cyclohexene ring with a ketone functional group, which is crucial for its odor profile. The presence of the conjugated double bond system contributes to its distinctive violet-like aroma, making it a valuable component in both flavor and fragrance formulations.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Alpha-ionone is renowned for its floral, woody, and fruity aroma, often described as reminiscent of violets. It exhibits a moderate to strong intensity with a high diffusion rate, making it an impactful note in compositions. The odor threshold of alpha-ionone is relatively low, allowing it to impart its characteristic scent even at minimal concentrations. In flavor applications, it serves as a modifier, enhancing the floral and fruity notes of a formulation. Its ability to blend seamlessly with other floral and fruity components makes it a versatile ingredient in both flavor and fragrance systems.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Alpha-ionone naturally occurs in a variety of plant sources, including violets, raspberries, and certain types of tea. It is formed through the oxidative degradation of carotenoids, such as beta-carotene, which are abundant in many fruits and vegetables. This compound is often associated with the "natural flavor" designation due to its presence in these natural sources. The enzymatic breakdown of carotenoids during processing or ripening leads to the formation of alpha-ionone, contributing to the characteristic aroma of many natural products.

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

4. Use in Flavors

In the flavor industry, alpha-ionone is utilized across various categories, including fruit, floral, and tea flavors. It plays a functional role as a modifier, enhancing the overall complexity and authenticity of flavor profiles. Typical use levels in finished food or beverage products range from 0.1 to 5 ppm, with industry-typical concentrations often falling between 0.5 and 2 ppm. Alpha-ionone is relatively stable under normal processing conditions, but it may degrade under extreme heat or acidic conditions, which should be considered during formulation.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

Alpha-ionone is a staple in the fragrance industry, commonly found in floral, woody, and fruity fragrance families. It serves as an impact note, providing a violet-like scent that enhances the floral character of a fragrance. Typical concentration ranges in fragrance formulations vary, but it is often used at levels of 0.1% to 1% depending on the desired intensity. Alpha-ionone contributes primarily to the middle notes of a fragrance, offering moderate volatility that allows it to blend well with both top and base notes.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

In the United States, alpha-ionone is recognized as GRAS (Generally Recognized As Safe) by FEMA for flavor use. In the European Union, it is listed under Regulation (EC) No 1334/2008 with the FL number 07.008. The United Kingdom follows similar regulations post-Brexit. In Asia, alpha-ionone is approved for use in Japan and China, with specific guidelines varying by country. In Latin America, countries like Brazil and those in MERCOSUR have harmonized regulations that generally align with international standards. However, formulators should verify specific country regulations due to potential variability.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

Alpha-ionone is considered safe for use in flavors and fragrances when used within recommended limits. For oral exposure, the acceptable daily intake (ADI) is not explicitly defined, but it is deemed safe under FEMA GRAS guidelines. Dermal exposure in fragrance applications is generally well-tolerated, with low potential for irritation or sensitization, as supported by IFRA standards. Inhalation exposure is considered safe at typical fragrance concentrations, though occupational exposure should be monitored to prevent overexposure. The risk profiles for food and fragrance applications are similar, with no significant differences noted.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Alpha-ionone is valued for its ability to impart a natural violet-like aroma, making it a sought-after ingredient in both flavor and fragrance formulations. It synergizes well with other floral and fruity notes, enhancing the overall complexity of a composition. Common formulation pitfalls include overuse, which can lead to an overpowering scent, and instability under extreme conditions. It is frequently under-used in formulations seeking a subtle floral enhancement, where its low odor threshold can be advantageous.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on alpha-ionone is well-established, with comprehensive sensory and regulatory information available. Industry practices are well-documented, though some variability in use levels and regulatory interpretations may exist. Known data gaps are minimal, with most information being consistent across authoritative sources.

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 2026-04-04 23:16:48 GMT (p2)