# Methyl Isobutanethioate

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> Markdown URL: https://additivefacts.com/additives/methyl-isobutanethioate.md

**Safety rating:** UNKNOWN
**CAS number:** 42075-42-3
**Category:** flavoring
**FDA GRAS:** no
**Adverse events (FDA AERS):** 0
**FDA recalls:** 0
**Last updated:** 2026-04-02

## Summary

Methyl isobutanethioate (CAS 42075-42-3) is a sulfur-containing organic compound used as a flavoring agent in food products. It imparts savory, meat-like, and umami-related taste characteristics to processed foods and beverages.

## 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 Methyl Isobutanethioate?

Methyl isobutanethioate is a synthetic organic flavoring compound belonging to the thioester chemical class. It is characterized by a molecular formula containing sulfur, which is responsible for its distinctive savory and meaty flavor profile. The compound is produced through chemical synthesis and functions as a flavoring agent or flavoring adjuvant in food manufacturing.

## Common Uses

Methyl isobutanethioate is primarily used in the food industry as a flavoring ingredient to enhance or create savory taste experiences. Its applications include:

- Processed meat products and meat analogs
- Savory snack foods
- Soups and broth-based products
- Seasoning blends and condiments
- Umami-enhancing food formulations
- Convenience foods requiring meat-like flavor profiles

The compound is typically used in very small quantities, as is standard practice with concentrated flavoring agents, to achieve desired taste profiles without contributing significantly to the overall composition of the final food product.

## Safety Assessment

Methyl isobutanethioate has not received FDA GRAS (Generally Recognized as Safe) status, indicating that it has not undergone the formal GRAS affirmation process. However, this classification does not indicate that the substance is unsafe; rather, it reflects that comprehensive safety documentation may not have been submitted to or evaluated by the FDA through the GRAS notification pathway.

Relevant safety data points include:

- No adverse events have been reported to the FDA related to this additive
- No FDA recalls have been issued involving this compound
- As a synthetic flavoring agent, exposure levels in food are typically minimal due to its use in low concentrations

The lack of reported adverse events and recalls suggests that if the compound is in use, it has not been associated with consumer health concerns at current usage levels. However, the absence of GRAS status means formal toxicological review data may be limited in the public domain.

## Regulatory Status

In the United States, methyl isobutanethioate's regulatory position differs from fully approved food additives:

- **FDA Status**: Not designated as GRAS
- **Authorization**: May be used under FDA regulation as a food additive if it meets specific regulatory requirements, though its approval status requires verification for specific applications
- **International Status**: Regulatory standing in other countries such as those in the European Union, Canada, or Japan may differ and should be verified through their respective food safety authorities

Manufacturers using this ingredient should ensure compliance with FDA regulations and maintain documentation supporting its safe use in their specific food applications. The regulatory landscape for synthetic flavoring agents continues to evolve as safety data becomes available.

## Key Studies

Published scientific literature specifically evaluating methyl isobutanethioate is limited in publicly available databases. Most safety assessments for synthetic flavor compounds rely on:

- Structure-activity relationship (SAR) evaluations
- Toxicology testing following OECD guidelines
- Metabolism and fate studies in animal models
- Human consumption data at typical exposure levels

For comprehensive safety information, stakeholders should consult:
- FDA's Food Additives Status List
- The Flavor and Extract Manufacturers Association (FEMA) Expert Panel resources
- Scientific literature in toxicology and food chemistry databases
- Individual manufacturer safety data sheets

The limited public data on this specific compound underscores the importance of manufacturers providing safety documentation to regulatory agencies and maintaining transparent communication with consumers about ingredient sourcing and safety protocols.

## 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. "Methyl Isobutanethioate — Safety, regulation, and evidence." https://additivefacts.com/additives/methyl-isobutanethioate. Accessed 2026-05-19.