Ethyl Carbamate in Fermented Beverages: Presence, Analytical Chemistry, Formation Mechanism, and Mitigation Proposals

Abstract

Ethyl carbamate (EC) commonly found in fermented beverages has been verified to be a multisite carcinogen in experimental animals. EC was upgraded to Group 2A by the Intl. Agency for Research on Cancer (IARC) in 2007, which indicates that EC is a probable carcinogen to humans. Because of its threat to human safety, the presence of EC may be a big challenge in the alcoholic beverage industry. During the past few years, thorough and systematic research has been carried out in terms of the generation of EC in order to meet the allowed limitation levels in fermented beverages. Previous studies have indicated that EC primarily results from the reaction of ethanol and compounds containing carbamyl groups. These main EC precursors are commonly generated from arginine metabolism by Saccharomyces cerevisiae or lactic acid bacteria accompanied by the fermentation process. This review comprehensively summarizes the genotoxicity, analytical methods, formation pathways, and removal strategies of EC in various beverages. The article also presents the metabolic mechanism of EC precursors and pertinent metabolites, such as urea, citrulline, and arginine.

Bacterial Diversity Analysis during the Fermentation Processing of Traditional Chinese Yellow Rice Wine Revealed by 16S rDNA 454 Pyrosequencing

“…Nowadays, safety issues of rice wine have caused widespread concern, such as the formation of ethyl carbamate (EC), biogenic amine and rancidification, and so on (Jiao and others ). EC is a probable carcinogen that has been found mainly as a byproduct of fermentation, especially in stone‐fruit spirits, such as grape wine, Japanese sake and Chinese yellow rice wine, and so on (Lachenmeier and others ; Fu and others ).…”

Assessing the Potential Content of Ethyl Carbamate in White, Red, and Rosé Wines as a Key Factor for Pursuing Urea Degradation by Purified Acid Urease

“…From Table it can be noted that the EC content in the rosé (sample F) and Moscato (sample C) wines after 24‐mo storage at approximately 30.2 °C would be highly likely smaller than the legal limit (30 μg/L) set for table wines by the Canadian legislation. On the contrary, in the table white wines (samples A and B), as well as the young and old red wines (samples D and E), the EC content would be by far greater than the above limit, thus asking for the application of one or more than 1 methods described by Jiao and others (). In this work, only the urea degradation process by purified acid urease was taken into account.…”

“…To reduce EC levels in wine, a number of preventive actions regarding the control of fertilization techniques, adjustment of nutrient contents in grape musts, use of suitable yeast and lactic acid bacteria strains, acid urease application, and control of storage conditions has been recommended by FDA (Butzke and Bisson ). Also several physical, chemical, enzymatic, and metabolic engineering methods are available to limit EC in fermented beverages (Zhao and others ; Jiao and others ). For instance, the enzymatic hydrolysis of urea to ammonia and CO 2 was regarded as the most convenient way to suppress EC formation from this source (Jiao and others ): …”

Chemical Analysis of Suspected Unrecorded Alcoholic Beverages from the States of São Paulo and Minas Gerais, Brazil

“…EC is formed from the reaction of ethanol and compounds containing carbamoyl groups. The main EC precursors are commonly generated from arginine metabolism by Saccharomyces cerevisiae or lactic acid bacteria, which is accompanied by the fermentation process [10, 11, 41, 42]. High EC content, reaching levels as high as hundreds of micrograms per liter, was detected in Brazilian sugarcane spirits [42].…”

“…High EC content, reaching levels as high as hundreds of micrograms per liter, was detected in Brazilian sugarcane spirits [42]. Such high concentrations were found in samples from the state of Minas Gerais and Pernambuco in many authors [10, 11, 29, 30, 41, 42]. …”