FlavScents AInsights Entry for para-Dimethyl Hydroquinone (CAS: 150-78-7)

1. Identity & Chemical Information

• Common Name(s): para-Dimethyl hydroquinone
• IUPAC Name: 2,5-Dimethylbenzene-1,4-diol
• CAS Number: 150-78-7
• FEMA Number: Not applicable
• Other Identifiers: Not available
• Molecular Formula: C8H10O2
• Molecular Weight: 138.17 g/mol

para-Dimethyl hydroquinone is a phenolic compound characterized by two methyl groups attached to a hydroquinone structure. The presence of hydroxyl groups contributes to its antioxidant properties, which are relevant in both flavor and fragrance applications. The compound's structure influences its odor profile, often described as sweet and phenolic.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

para-Dimethyl hydroquinone is known for its sweet, phenolic odor with moderate intensity. It is often used as a background note to enhance the complexity of a fragrance or flavor profile. The compound's sensory characteristics make it suitable for use as a modifier, adding depth and richness to formulations. Specific odor and taste thresholds are not well-documented, but its impact is generally considered subtle yet noticeable.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

para-Dimethyl hydroquinone is not commonly found in nature but can be synthesized through chemical processes. It is not typically associated with natural flavor or fragrance designations due to its synthetic origin. The compound can be formed through the methylation of hydroquinone, a process often utilized in industrial settings.

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

4. Use in Flavors

In flavor applications, para-dimethyl hydroquinone is used to impart a sweet, phenolic note that can enhance the overall profile of a product. It is typically employed in low concentrations, often below 10 ppm, to avoid overpowering other flavor components. Its stability under various conditions, such as heat and pH, makes it a versatile ingredient in flavor systems. However, formulators should be cautious of its potential to oxidize, which can alter its sensory characteristics.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

para-Dimethyl hydroquinone is utilized in fragrance formulations for its ability to add a sweet, phenolic nuance. It is commonly found in woody and oriental fragrance families, where it serves as a modifier or impact note. Typical concentrations in fragrance products range from trace amounts to 0.1%, depending on the desired effect. Its volatility allows it to contribute to both the middle and base notes of a fragrance composition.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: para-Dimethyl hydroquinone is not explicitly listed as GRAS by FEMA for flavor use. Its use in fragrances is subject to IFRA guidelines.
• European Union: Not specifically listed under Regulation (EC) No 1334/2008 for flavor use. Fragrance use is regulated under general safety standards.
• United Kingdom: Follows EU regulations post-Brexit with no significant divergence reported.
• Asia: Limited specific regulatory information available; general safety standards apply.
• Latin America: Regulatory status varies; formulators should consult local regulations.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

• Oral Exposure: Limited data on acceptable daily intake (ADI) or threshold of toxicological concern (TTC) for flavor use. Formulators should adhere to industry-typical low concentrations.
• Dermal Exposure: Generally considered safe in fragrance applications at typical use levels. IFRA guidelines should be consulted to avoid irritation or sensitization.
• Inhalation Exposure: Volatility suggests potential for inhalation exposure, but no specific occupational hazards reported at typical use levels.

Risk profiles may differ between food and fragrance applications, with fragrance use generally posing lower systemic exposure risks.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

para-Dimethyl hydroquinone is valued for its ability to enhance the complexity of both flavors and fragrances. It synergizes well with other phenolic compounds and can be used to add depth to woody and oriental profiles. Formulators should be mindful of its oxidation potential, which can affect stability and sensory characteristics. Overuse can lead to an overpowering phenolic note, so careful calibration is essential.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on para-dimethyl hydroquinone is well-established in terms of its chemical identity and sensory profile. However, specific regulatory and toxicological data are less comprehensive, requiring formulators to rely on industry-typical practices and guidelines. Known data gaps include detailed exposure thresholds and comprehensive regional regulatory information.

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
• Section 5a is not applicable as para-dimethyl hydroquinone is a single compound

If any item is missing, immediately revise the entry to fix it before returning the final output.

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 2026-02-07 18:32:22 GMT (p2)