# L-fenchone

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> Markdown URL: https://additivefacts.com/additives/l-fenchone.md

**Safety rating:** UNKNOWN
**CAS number:** 7787-20-4
**Category:** flavoring
**FDA GRAS:** no
**Adverse events (FDA AERS):** 0
**FDA recalls:** 0
**Last updated:** 2026-04-02

## Summary

L-fenchone is a naturally occurring organic compound classified as a flavoring agent. It is derived from fennel and other botanical sources, and is used in the food industry to provide characteristic aromatic and taste properties to various food products.

## Regulatory status

| Country | Status |
| --- | --- |
| United States | approved |
| European Union | not_evaluated |
| United Kingdom | not_evaluated |
| Canada | not_evaluated |
| Australia | not_evaluated |
| Japan | not_evaluated |
| South Korea | not_evaluated |
| Brazil | not_evaluated |
| China | not_evaluated |
| India | not_evaluated |

## Detailed analysis

## What is L-fenchone?

L-fenchone (CAS Number 7787-20-4) is a bicyclic ketone compound that occurs naturally in essential oils of fennel, anise, and other aromatic plants. It is the levorotatory enantiomer of fenchone, meaning it rotates polarized light to the left. As a volatile organic compound, L-fenchone contributes to the distinctive aromatic profile of fennel-based flavoring systems. The compound is a colorless to pale yellow liquid with a characteristic warm, spicy, and herbaceous odor.

## Common Uses

L-fenchone functions as a flavoring agent and flavoring adjuvant in the food industry. It is utilized in small quantities to impart or enhance fennel-like, anise-like, and herbal notes in various food products. Common applications include:

- Beverages (alcoholic and non-alcoholic)
- Confectionery and candy products
- Baked goods and bread products
- Dairy products
- Seasonings and spice blends
- Herbal tea formulations

Because L-fenchone is naturally present in the botanical sources from which fennel flavoring is derived, it represents one component of traditional fennel flavor preparations used for centuries in culinary applications.

## Safety Assessment

L-fenchone has not been formally evaluated by the FDA for GRAS (Generally Recognized As Safe) status. However, this classification does not necessarily indicate safety concerns; rather, it reflects that formal GRAS notification or petition has not been submitted to the FDA for this specific compound.

The compound has not generated any adverse event reports in the FDA database, and there are no documented FDA recalls associated with L-fenchone. As a naturally occurring component of fennel essential oil, which has a long history of use in food applications, L-fenchone carries an implicit safety profile based on traditional use. However, the absence of formal GRAS status means its use in food products in the United States is subject to FDA regulations for food additives.

The European Food Safety Authority (EFSA) has evaluated fenchone as a flavoring substance. In the EFSA's assessment of flavoring compounds used in food, fenchone (including both enantiomers) has been evaluated within the context of botanical flavoring preparations. The EFSA's Panel on Food Additives and Nutrient Sources added to Food (ANS) considers such compounds acceptable for use when they are components of traditionally used botanical flavoring sources.

Toxicological studies on fenchone and related compounds suggest a low order of toxicity when used at levels typical in food flavoring applications. The rapid metabolism and elimination of such volatile compounds supports their safety at food-use concentrations.

## Regulatory Status

In the United States, L-fenchone is not on the GRAS list, meaning it is technically subject to food additive regulations if used intentionally in food products. However, it may be used as a component of natural flavoring complexes derived from fennel and related plants, which can be used under FDA regulations for natural flavors.

In the European Union, fenchone is listed as a flavoring substance in the Register of Flavoring Substances and may be used in food products according to EU Regulation (EC) No 1334/2008, which governs the use of flavoring substances.

Other countries' regulatory frameworks vary, with some allowing its use within traditional botanical flavoring preparations and others requiring specific approvals.

## Key Studies

Limited published literature exists specifically on L-fenchone in isolation. Most safety data derives from studies on fennel essential oil and fenchone as a component thereof. These studies generally support the safety of fenchone at levels encountered in food applications.

Research on fennel and its constituents indicates that the compound undergoes hepatic metabolism and is rapidly eliminated, consistent with a low toxicity profile for volatile ketones. The EFSA's flavor evaluation documents provide the most comprehensive current assessment of fenchone's safety in food use contexts.

## Sources

- FDA Substances Added to Food (CFSAN)
- OpenFDA Adverse Event Reporting System (AERS)
- OpenFDA Food Recalls
- EFSA OpenFoodTox
- EU Food Additive Portal

## Citation

Additive Facts. "L-fenchone — Safety, regulation, and evidence." https://additivefacts.com/additives/l-fenchone. Accessed 2026-05-19.