The trial was carried out to assess the ability of several yeast species associated with wine related environments to produce 4-ethylphenol in synthetic media containing p-coumaric acid. The yeast strains tested came from culture collections or were isolated in the ISA (Instituto Superior de Agronomia, Lisboa, Portugal) laboratories. The production of volatile phenols and the cellular fatty acid methyl ester compositions of the yeasts were investigated. Conversion rates up to 90% were found by Dekkera bruxellensis, D. anomala and by some unidentified strains isolated from wine-related environments. The production of 4-ethylphenol was also assessed for all unidentified strains. Further identification, by restriction pattern generated from PCR-amplification of the 5.8S rRNA gene and the two internal transcribed spacers (ITS), assigned those unidentified strains to Candida cantarelli, C. wickerhamii, Debaryomyces hansenii, Kluyveromyces lactis and Pichia guilliermondii. Some of them produced just traces of 4-ethylphenol. Only some strains of P. guilliermondii were capable of converting p-coumaric acid into 4-ethylphenol with efficiencies close to those observed in D. bruxellensis and D. anomala. Authors suggest that this is the first report of P. guilliermondii as a strong 4-ethylphenol producer. D. bruxellensis remains as the sole agents of ‘‘phenolic off-flavours’’ in wines. (We suggest you to read the entire article.Original Title: Identification of yeasts isolated from wine-related environments and capable of producing 4-ethylphenol)