What is 3-hydroxy-5-methyl-2-hexanone?
3-hydroxy-5-methyl-2-hexanone (CAS Number: 163038-04-8) is an organic ketone compound with hydroxyl functional groups. It belongs to the class of naturally-inspired synthetic flavoring molecules commonly used in the food industry. The compound has a molecular formula of C7H14O2 and exists as a liquid at room temperature with a characteristic fruity aroma profile.
Common Uses
This flavoring agent is employed primarily in the formulation of:
- Flavored beverages (soft drinks, fruit juices, flavored water)
- Confectionery products (candies, chewing gum)
- Baked goods and snack foods
- Dairy products (yogurts, flavored milk)
- Frozen desserts
The compound contributes fruity and slightly floral notes that enhance the sensory profile of these products. Like other synthetic flavoring agents, it is typically used in very small concentrations—often measured in parts per million—to achieve the desired flavor intensity.
Safety Assessment
3-hydroxy-5-methyl-2-hexanone has not been formally evaluated by the FDA under the Generally Recognized As Safe (GRAS) designation process, meaning it does not have explicit GRAS status. However, the FDA's adverse event reporting system contains zero reported adverse events associated with this additive, and there have been no FDA-issued recalls linked to its use in food products.
The lack of adverse events and recalls suggests that where this compound has been used in food applications, no significant safety concerns have been identified by consumers or regulatory authorities. The absence of negative data does not constitute formal safety approval but indicates no documented harm from current usage patterns.
As a flavoring agent, this compound would be used only in trace amounts in food products, which minimizes potential exposure. Standard food safety principles apply: flavoring agents are incorporated at concentrations many times lower than those typically used in toxicological studies.
Regulatory Status
In the United States, 3-hydroxy-5-methyl-2-hexanone is not classified as a GRAS substance by the FDA. This means it does not have blanket approval for use in foods and would require pre-market approval or authorization through an alternative regulatory pathway if used intentionally as a food ingredient. Some manufacturers may use this compound under the FDA's Flavor and Extract Manufacturers' Association (FEMA) GRAS (GRAS) framework, which operates parallel to FDA GRAS determinations.
Regulatory status varies internationally. The European Food Safety Authority (EFSA) maintains separate approval lists for flavoring substances, and approval varies by jurisdiction. Manufacturers intending to use this additive should verify current regulatory compliance in their specific markets and jurisdictions.
Key Studies
Published literature on 3-hydroxy-5-methyl-2-hexanone in food safety applications is limited, reflecting its specialized use as a minor flavoring component. The compound's safety profile for food use has not been extensively documented in peer-reviewed literature, which is not unusual for synthetic flavoring agents used at extremely low concentrations.
Structurally similar compounds in the ketone and alcohol families have been evaluated for safety in food applications. General toxicology principles suggest that compounds with similar chemical structures to approved flavoring agents typically undergo comparable safety assessment protocols, though individual compounds require their own evaluation.
The absence of regulatory approval and the lack of published safety studies suggest that this particular compound's use in foods remains limited or that use levels remain below regulatory scrutiny thresholds in jurisdictions where it is permitted.