FlavScents AInsights Entry for Citral (CAS: 5392-40-5)

1. Identity & Chemical Information

Citral, a key component in the flavor and fragrance industry, is known by several names, including lemonal. Its IUPAC name is 3,7-dimethyl-2,6-octadienal. The CAS number for citral is 5392-40-5, and it is recognized by FEMA with the number 2303. Other identifiers include the FL number 05.015 and CoE number 140. Citral has the molecular formula C10H16O and a molecular weight of 152.23 g/mol. It consists of two geometric isomers: geranial (trans-citral) and neral (cis-citral), which contribute to its characteristic lemon scent. The aldehyde functional group in citral is crucial for its odor profile, providing a fresh, citrusy aroma that is highly valued in both flavor and fragrance formulations.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Citral is renowned for its strong, fresh lemon scent, often described as citrusy, zesty, and slightly sweet. It is a high-impact aroma compound with a significant diffusion and intensity, making it a prominent top note in fragrance compositions. The odor threshold of citral is relatively low, allowing it to be perceived at minimal concentrations. In flavor applications, citral imparts a lemon-like taste, enhancing the freshness and brightness of citrus flavors. It serves as an impact note, providing a realistic lemon character to both flavors and fragrances.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Citral naturally occurs in the essential oils of several plants, most notably in lemongrass (Cymbopogon citratus), lemon myrtle (Backhousia citriodora), and the peel of citrus fruits. It is biosynthesized in plants through the isoprenoid pathway, where it functions as a precursor to other terpenoids. Citral's presence in natural sources qualifies it for "natural flavor" or "natural fragrance" designations, depending on the extraction and processing methods used.

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

4. Use in Flavors

In the flavor industry, citral is extensively used to impart a lemony taste to a wide range of products, including beverages, confectionery, and baked goods. It functions as a primary flavoring agent, providing both impact and authenticity to citrus profiles. Typical use levels in finished food products range from 1 to 30 ppm, with higher concentrations used in more robust citrus flavors. Citral is sensitive to heat and oxidation, which can lead to degradation and loss of flavor intensity, thus requiring careful formulation and storage considerations.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

Citral is a versatile ingredient in the fragrance industry, commonly used in citrus, floral, and fresh fragrance families. It acts as a top note, providing an immediate burst of freshness and realism. Typical concentration ranges in fragrance formulations vary from trace amounts to several percent, depending on the desired intensity and product type. Citral's volatility makes it an excellent choice for top note applications, although it may require stabilization to prevent degradation.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

In the United States, citral is generally recognized as safe (GRAS) for use in food by FEMA. The European Union lists citral under Regulation (EC) No 1334/2008 with the FL number 05.015, allowing its use in food flavorings. The United Kingdom, post-Brexit, aligns with EU regulations. In Asia, citral is approved for use in Japan and China, with specific guidelines under ASEAN regulations. In Latin America, countries like Brazil and those in MERCOSUR recognize citral's use in both flavors and fragrances, although specific limits may vary.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

Citral's safety profile is well-documented, with an acceptable daily intake (ADI) established by EFSA. For oral exposure, citral is considered safe within the typical use levels in food. Dermal exposure in fragrances may cause irritation or sensitization in sensitive individuals, and it is subject to IFRA standards to mitigate these risks. Inhalation exposure is generally low risk due to citral's volatility and rapid dispersion. The risk profiles for food and fragrance applications are similar, with appropriate use levels ensuring consumer safety.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Citral is valued for its potent lemon aroma and flavor, making it a staple in citrus formulations. It synergizes well with other citrus and floral notes, enhancing freshness and complexity. Formulators should be cautious of citral's sensitivity to heat and oxidation, which can lead to degradation. Overuse can result in an overpowering or artificial lemon note, while underuse may fail to achieve the desired impact. Balancing citral with stabilizers and antioxidants can enhance its longevity in formulations.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on citral is robust, with well-established sensory and safety profiles supported by extensive research and industry practice. While most regulatory and safety information is well-documented, some regional variations in regulatory limits may exist. Industry practices for citral use are generally consistent, although specific formulation techniques may vary.

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 for citral)

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 2026-08-27 17:42:34 GMT (p2)