What is Trans-2-nonen-1-ol?
Trans-2-nonen-1-ol (CAS Number 31502-14-4) is an unsaturated aliphatic alcohol belonging to the class of volatile organic compounds used in the food industry. It is a colorless to pale yellow liquid with a characteristic fruity aroma. The compound exists naturally in small quantities in various fruits and plant materials, though it is typically synthesized for commercial food applications. Its molecular structure contains a nine-carbon chain with a hydroxyl group and a double bond in the trans configuration.
Common Uses
Trans-2-nonen-1-ol is primarily employed as a flavoring agent and flavor enhancer in the food and beverage industry. It is commonly used in:
- Flavored beverages including juices, soft drinks, and alcoholic drinks
- Confectionery products and chewing gums
- Baked goods and desserts
- Dairy products and yogurts
- Processed snacks and savory products
The compound contributes fruity, floral, and slightly herbal notes that enhance the sensory profile of food products. Typical usage levels are very low, measured in parts per million (ppm), as the compound is potent in its aromatic effect.
Safety Assessment
Trans-2-nonen-1-ol has not been designated as Generally Recognized as Safe (GRAS) by the FDA, which means it has not undergone the formal GRAS notification process. However, this classification does not indicate the compound is unsafe; rather, it reflects the regulatory pathway taken by manufacturers. The FDA has received zero adverse event reports associated with this additive and has issued zero recalls involving trans-2-nonen-1-ol, suggesting no documented safety incidents in the U.S. food supply.
The European Food Safety Authority (EFSA) has evaluated structurally related aliphatic alcohols used in flavoring, with many receiving positive safety assessments when used at appropriate levels. Trans-2-nonen-1-ol is similar in structure to other nine-carbon alcohols that have been evaluated for safety in food applications.
Safety data on trans-2-nonen-1-ol is limited in published scientific literature, which is typical for compounds used at very low concentrations in food. The lack of extensive human toxicology studies reflects both the minimal exposure levels and the historical use of such compounds without documented harm. Any safety assessment must consider that the actual dietary exposure to this compound from food sources is extremely low due to its intended use at trace levels.
Regulatory Status
Trans-2-nonen-1-ol is not approved as a food additive in the European Union under the current additives regulations, though it may be permitted as a flavoring substance under specific legislative frameworks governing flavoring compounds. In the United States, while not GRAS-affirmed, it may be used in foods under FDA regulations if manufacturers have adequate safety data and follow proper notification procedures. The regulatory status varies by country and specific food application.
Manufacturers using this ingredient should maintain current documentation of safety data and comply with local regulatory requirements in their target markets. The ingredient is generally not listed prominently on consumer-facing labels due to its classification as a processing aid or flavor enhancer in many jurisdictions.
Key Studies
Published scientific literature specifically examining trans-2-nonen-1-ol is limited. Safety assessments of this compound must be extrapolated from studies of structurally similar volatile aliphatic alcohols. Research on related nine-carbon saturated and unsaturated alcohols indicates low acute toxicity and minimal bioaccumulation potential. The metabolic pathways for similar compounds typically involve oxidation to corresponding aldehydes and carboxylic acids, followed by normal elimination routes.
Current safety assessments rely on chemical structure-activity relationship (SAR) analysis, which compares trans-2-nonen-1-ol to extensively studied analogues. This approach, combined with zero documented adverse events in regulatory databases, supports the continued use of this ingredient at established low concentration levels in food applications.