What is Cis and Trans-5-ethyl-4-methyl-2-(2-methylpropyl)-thiazoline?
Cis and trans-5-ethyl-4-methyl-2-(2-methylpropyl)-thiazoline (CAS Number: 83418-53-5) is a synthetic organic compound belonging to the thiazoline class of flavor chemicals. Thiazolines are heterocyclic compounds containing a five-membered ring with nitrogen and sulfur atoms. This particular compound exists in two geometric isomers—cis and trans forms—which may contribute differently to the overall flavor profile. The molecule is characterized by its ethyl, methyl, and isobutyl substituents, which influence its organoleptic properties.
Common Uses
This flavoring agent is used in the food industry to create complex savory notes, particularly meaty and roasted flavor characteristics. Due to its potency, it is typically employed in very small concentrations—often measured in parts per million (ppm)—in processed foods such as soups, broths, gravies, seasonings, and savory snack products. It may also be used in certain meat analogs and plant-based protein products where authentic savory profiles are desired. The compound is valued for its ability to enhance umami perception and replicate natural meat flavors in formulated foods.
Safety Assessment
As of the available data, there have been zero recorded adverse events reported to the FDA related to this additive, and no food recalls have been associated with its use. The absence of adverse event reports and recalls suggests a favorable safety profile in current food applications. However, it is important to note that this compound has not been granted GRAS (Generally Recognized As Safe) status by the FDA, meaning it has not undergone the formal GRAS affirmation process or petition procedure for regulatory approval in the United States.
The safety of thiazoline-based flavorings generally relies on their use at extremely low concentrations and their structural similarity to naturally occurring flavor compounds. Thiazolines with similar structures have been studied for potential toxicity, and most show low systemic toxicity when evaluated at relevant dietary exposure levels. However, comprehensive toxicological data specific to this particular isomeric mixture may be limited in publicly available literature.
As with all synthetic flavoring agents, safety depends critically on compliance with established usage levels and manufacturing purity standards. Impurities or contaminants introduced during synthesis could theoretically pose concerns, making supplier quality control essential.
Regulatory Status
In the United States, while this compound does not have FDA GRAS status, it may be used in food if it complies with FDA regulations for food additives and permitted flavoring substances. The FDA maintains a list of synthetic flavoring substances that are permitted for use, and this compound's regulatory standing should be verified through current FDA guidance documents or direct inquiry with manufacturers.
Regulatory status varies by jurisdiction. The European Union has established strict requirements for flavor additives through Regulation (EC) No 1334/2008, and inclusion on the Union List is necessary for use in EU member states. Manufacturers should verify compliance with applicable regulations in their target markets before use.
Key Studies
Published scientific literature specifically addressing the toxicology of this particular compound appears limited in publicly accessible databases. The safety assessment likely draws upon structural analogs, thiazoline chemistry principles, and general toxicological knowledge of similar flavor compounds. Any manufacturer or regulatory agency evaluating this additive would typically conduct or review studies on acute toxicity, repeated-dose toxicity, genotoxicity, and reproductive/developmental toxicity—the standard battery for flavor chemical evaluation.
Researchers studying thiazoline flavorings have generally concluded that these compounds present low toxicological concern when used at approved flavor levels, though compound-specific data strengthens regulatory confidence. Any new research or safety reviews should be documented and made available to regulatory authorities.