Butanethiol

Butanethiol (CAS 109-79-5), also known as n-butyl mercaptan, is a sulfur-containing organic compound used commercially as an odorant and flavoring agent. Its intensely low odor threshold makes it effective for gas leak detection and trace-level sensory applications. FEMA 3478 designates it as an approved flavoring substance for food use. In the oil and gas industry, butanethiol is blended into natural gas and LPG as a stenching agent, providing the characteristic warning odor.

This warning odor enables leak detection at extremely low concentrations. Food and beverage formulators use it at trace levels to contribute sulfurous, onion-like, or savory top notes in processed flavors for various applications. It functions as a building block in flavor systems targeting meat, roasted, and allium profiles. Fragrance and flavor houses also incorporate it into reference standards and specialty aroma compositions requiring controlled sulfur character.

Butanethiol is supplied as a liquid, typically in small containers suited to its high odor intensity and handling requirements. It is available in technical grade for industrial odorant applications and in food-grade specifications. The material is compliant with FEMA and relevant flavor safety standards. Packaging ranges from laboratory-scale quantities to drum volumes depending on end-use volume requirements and specific industrial or food-grade needs.