FlavScents AInsights Entry for WS-23 (CAS: 51115-67-4)

1. Identity & Chemical Information

• Common Name(s): WS-23
• IUPAC Name: 2-Isopropyl-N,2,3-trimethylbutanamide
• CAS Number: 51115-67-4
• FEMA Number: Not available
• Other Identifiers: Not available
• Molecular Formula: C10H21NO
• Molecular Weight: 171.28 g/mol

WS-23 is a synthetic cooling agent known for its ability to impart a cooling sensation without the minty flavor associated with menthol. Its structure includes an amide functional group, which is crucial for its cooling effect. The compound's cooling sensation is attributed to its interaction with the TRPM8 receptor, which is responsible for sensing cold temperatures.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

WS-23 is characterized by its potent cooling effect, which is perceived as clean and refreshing. Unlike menthol, WS-23 does not have a strong odor, making it ideal for applications where a cooling sensation is desired without altering the flavor profile. The intensity of the cooling effect is moderate to strong, and it is often used as an impact note in formulations. The taste threshold for WS-23 is relatively low, allowing for effective use at minimal concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

WS-23 is a synthetic compound and does not occur naturally. It is produced through chemical synthesis, typically involving the reaction of isopropylamine with a suitable acid chloride. As a synthetic cooling agent, WS-23 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

WS-23 is widely used in the flavor industry to impart a cooling sensation in various products, including beverages, confectionery, and oral care products. It is particularly popular in mint-flavored products where a cooling effect is desired without the minty taste. Typical use levels in finished products range from 10 to 100 ppm, with higher concentrations used in applications requiring a more pronounced cooling effect. WS-23 is stable under a wide range of pH conditions and is resistant to degradation by heat and oxidation.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, WS-23 is used to add a cooling effect to personal care products, such as lotions and shampoos. It is often used in conjunction with other cooling agents to enhance the overall sensory experience. WS-23 contributes primarily to the top notes of a fragrance, providing an immediate cooling sensation upon application. Typical concentrations in fragrance formulations range from 0.1% to 1%.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: WS-23 is not explicitly listed as GRAS by FEMA but is used in accordance with good manufacturing practices.
• European Union: Not specifically listed under Regulation (EC) No 1334/2008; usage is subject to general safety assessments.
• United Kingdom: Follows EU regulations post-Brexit with no significant divergence reported.
• Asia: Usage varies; Japan and China require specific safety assessments for new additives.
• Latin America: Regulatory status varies; Brazil and MERCOSUR countries typically align with international safety standards.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

WS-23 is considered safe for use in food and fragrance applications when used within recommended concentrations. Oral exposure through flavor use is generally regarded as safe, with no specific ADI or MSDI established. Dermal exposure in fragrance applications has not shown significant irritation or sensitization potential, aligning with IFRA guidelines. Inhalation exposure is minimal due to low volatility, but occupational safety measures should be observed during handling.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

WS-23 is valued for its ability to provide a cooling sensation without altering the flavor profile, making it versatile across various applications. It synergizes well with other cooling agents like menthol and WS-3, enhancing the overall cooling effect. Formulators should be cautious of overuse, as excessive concentrations can lead to an overpowering sensation. It is often under-utilized in non-mint applications where a subtle cooling effect could enhance consumer experience.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on WS-23 is well-established, with extensive industry use supporting its safety and efficacy. While specific regulatory approvals may vary, industry practices provide a reliable framework for its application. Known data gaps include specific ADI values, which are typically addressed through industry-typical usage 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 2026-06-09 07:29:12 GMT (p2)