Reduction of ochratoxin a levels in white wine by yeast treatments

Abstract

This paper describes the abilities of 21 yeast strains isolated from six different wine-grapes of Turkey to bind ochratoxin A (OTA). Viable (108 CFU/mL) and heat-treated yeast cells were incubated both in phosphate-buffered saline (PBS) and white wine containing 10 ng OTA per mL for 4 h at 25°C. After centrifugation, the concentration of OTA was measured in the supernatant fraction using a high-performance liquid chromatography system coupled with fluorescence detector. The adsorption abilities of OTA by viable yeast strains within 4 h ranged from 1.96 to 26.11% in PBS. On the other hand, a slight decrease was observed in the percentage of OTA removal by yeast strains in white wine when compared to their activity in PBS. The addition of yeasts at 108 CFU/mL resulted in a reduction to a maximum of 21.40% in white wine, with respect to the control. Among the yeasts, Candida famata D7 was found to be the most efficient binder to OTA both in spiked white wine and PBS. In addition, dead yeast cells can potentially be used for removing OTA (a maximum of 30.45%) from white wine.