FlavScents AInsights Entry for Dextro-Limonene (CAS: 5989-27-5)

1. Identity & Chemical Information

• Common Name(s): Dextro-limonene, (R)-limonene
• IUPAC Name: (R)-1-methyl-4-(1-methylethenyl)cyclohexene
• CAS Number: 5989-27-5
• FEMA Number: 2633
• Other Identifiers: FL No. 02.015
• Molecular Formula: C10H16
• Molecular Weight: 136.24 g/mol

Dextro-limonene is a monocyclic monoterpene with a characteristic citrus odor. Its structure consists of a cyclohexene ring with a methyl and an isopropenyl group, contributing to its distinctive scent profile. The presence of the isopropenyl group is crucial for its odor characteristics, providing a fresh, zesty citrus note.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Dextro-limonene is renowned for its fresh, sweet citrus aroma, reminiscent of oranges and lemons. It is a high-impact odorant with a strong diffusion and moderate intensity. The compound is often used as a top note in fragrance compositions due to its volatility and bright, uplifting scent. The odor threshold is relatively low, making it effective even at minimal concentrations.

In flavor applications, dextro-limonene imparts a citrusy taste, enhancing the freshness and juiciness of fruit flavors. It serves as both an impact note and a modifier, adding realism and complexity to flavor profiles.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Dextro-limonene is naturally found in the rinds of citrus fruits such as oranges, lemons, and limes. It is a major component of citrus essential oils, particularly orange oil, where it can constitute up to 90% of the oil's composition. The compound is biosynthesized in plants via the mevalonate pathway, a key route for the formation of terpenes.

Its natural occurrence in citrus fruits qualifies it for use in "natural flavor" and "natural fragrance" designations, aligning with consumer preferences for natural ingredients.

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

4. Use in Flavors

Dextro-limonene is extensively used in flavor formulations, particularly in citrus-flavored products such as beverages, candies, and baked goods. It acts as a flavor enhancer, providing a fresh, juicy citrus note that complements other fruit flavors.

Typical use levels in finished food products range from 10 to 100 ppm, with higher concentrations used in more robust citrus profiles. It is generally stable under acidic conditions but can degrade under prolonged heat exposure, leading to potential off-flavors.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, dextro-limonene is a key component in citrus, fresh, and fruity fragrance families. It is used in a variety of products, including perfumes, colognes, and household cleaners, to impart a clean, invigorating scent.

Dextro-limonene typically functions as a top note due to its high volatility, providing an initial burst of freshness. Concentration ranges in fragrance formulations vary widely, often between 0.1% and 5%, depending on the desired intensity and product type.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Recognized as GRAS by FEMA for flavor use. No specific restrictions for fragrance use.
• European Union: Approved for use in food flavorings under Regulation (EC) No 1334/2008. Listed with FL No. 02.015.
• United Kingdom: Follows EU regulations post-Brexit with no significant divergence.
• Asia: Approved for use in Japan and China, with specific concentration limits in certain applications.
• Latin America: Generally accepted in Brazil and MERCOSUR countries, with harmonized standards for flavor and fragrance use.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

Dextro-limonene is considered safe for use in food and fragrance applications, with a high margin of safety.

• Oral Exposure: The compound has a high ADI, with no significant toxicological concerns at typical use levels.
• Dermal Exposure: Generally non-irritating and non-sensitizing, though IFRA recommends concentration limits in leave-on products to minimize potential sensitization.
• Inhalation Exposure: Low volatility reduces occupational exposure risks, but adequate ventilation is recommended in industrial settings.

Risk profiles are similar across food and fragrance applications, with no significant differences in safety considerations.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Dextro-limonene is valued for its ability to impart a fresh, authentic citrus note, making it indispensable in both flavor and fragrance formulations. It synergizes well with other citrus and fruity notes, enhancing overall freshness and appeal.

Common pitfalls include overuse, which can lead to overpowering or artificial profiles, and instability under heat, which can cause degradation. Formulators should balance its use with stabilizers or antioxidants to maintain integrity.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on dextro-limonene is well-established, with extensive documentation in both flavor and fragrance contexts. Industry practices are well-documented, though some regional regulatory nuances may require further verification. No significant data gaps or ambiguities are noted.

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 2026-03-09 07:16:08 GMT (p2)