Effect of ethanol on the ability of Oenococcus oeni to remove ochratoxin A in synthetic wine-like media

The study focused on the changes in bacterial population, malolactic fermentation and ochratoxin A (OTA) levels in cultures of Oenococcus oeni performed in synthetic medium supplemented with ethanol and OTA. Growth was better in cultures containing 5% ethanol and was not observed in cultures containing 15% ethanol. The OTA removal ability of O. oeni depended on ethanol and initial OTA levels. The highest toxin removal percentage was observed in cultures containing 5% ethanol and 2 μg OTA/l. In ethanol-containing medium part of OTA was not sorbed by O. oeni and remained in the liquid medium. Thus, it cannot efficiently eliminate OTA in acidic ethanol-containing beverages, such as wine. The effect of ethanol on the OTA removal ability of O. oeni is described for the first time.