What is (E)-2-Hexenyl Butyrate?
(E)-2-hexenyl butyrate, identified by CAS number 53398-83-7, is a synthetic ester belonging to the class of compounds known as volatile flavor compounds. It is chemically derived from butyric acid and hexenol, and exists as a clear to pale yellow liquid with a fruity, fresh, and slightly green aroma profile. This compound is one of many ester-based flavorings used in the food industry to replicate natural flavor notes found in fruits and other botanical sources.
Common Uses
As a flavoring agent, (E)-2-hexenyl butyrate is used in very small concentrations in various food and beverage applications. Its primary applications include flavoring in processed foods, beverages, confectionery, and dairy products where fruity or fresh green notes are desirable. Like most synthetic flavor compounds, it is typically used at parts-per-million (ppm) levels, meaning only trace amounts are necessary to achieve the desired sensory effect. The compound is particularly valued in the beverage industry for imparting fresh, fruit-forward characteristics without adding actual fruit ingredients.
Safety Assessment
The safety profile of (E)-2-hexenyl butyrate is supported by the absence of any reported adverse events to the FDA and zero documented recalls associated with this ingredient. As a synthetic ester, it belongs to a well-established class of flavor compounds that have been used in the food industry for decades. The low usage levels typical for ester-based flavorings further minimize any potential exposure concerns. No significant toxicological flags have been identified in available scientific literature regarding this specific compound at food-use levels.
The compound undergoes typical metabolic pathways when ingested, being hydrolyzed into its component parts—butyric acid and hexenol—both of which have well-established safety profiles in food applications. Butyric acid is a naturally occurring short-chain fatty acid found in butter and other dairy products, while hexenol compounds are present naturally in various fruits and vegetables.
Regulatory Status
(E)-2-hexenyl butyrate is not listed as Generally Recognized As Safe (GRAS) by the FDA, which means it has not undergone the formal GRAS notification process. However, this does not indicate a safety concern; rather, it reflects the regulatory pathway chosen by manufacturers and suppliers. The compound is permitted for use in food flavorings under FDA regulations for synthetic flavoring substances. Its legal status in the United States allows its use in food applications, and it is recognized in flavor ingredient databases maintained by flavor manufacturers and regulatory bodies.
In the European Union, similar ester-based flavoring compounds are evaluated under the European Flavoring Regulation, which maintains safety thresholds for volatile flavor components. The absence of regulatory restrictions on this ingredient reflects confidence in its safety profile when used in intended applications.
Key Studies
While (E)-2-hexenyl butyrate does not have extensive published clinical literature specifically devoted to it—which is typical for narrow-use synthetic flavor ingredients—its safety is supported by the broader scientific understanding of short-chain esters and their metabolism in humans. The chemical structure and properties place it within established categories of flavoring compounds that have been evaluated for safety by regulatory bodies and flavor industry scientific panels.
The lack of adverse event reports and recalls, combined with its use in extremely small concentrations, provides practical evidence of safety in real-world food applications. Continued monitoring through the FDA's adverse event reporting system serves as an additional safeguard for consumer protection.