Evolution of ochratoxin A content from must to wine an a pilot scale vinification process.

PONSONE, L.; COMBINA, M.; DALCERO, A.; CHULZE, S.N

Estambul, Turquía

Congreso; XII IUPAC Symposium on Mycotoxinsa and Phycotoxins; 2007

Ochratoxin A (OTA) is a nephrotoxic and carcinogenic mycotoxin, and also showed teratogenic, immunotoxic and possibly neurotoxic and genotoxic properties. The occurrence of this toxin has been reported in various vegetable products, such as cereals, grapes, beer and wine.The aim of this work was to evaluate the evolution of OTA content from must to wine during the red wine making process, in a pilot scale vinification. The study was done using most from one red grape variety (Bonarda) cultivated under two different cropping practices (organic and conventional). A set of four tanks (100 L each) was established with must from Bonarda (conventional and organic) and inoculated with two S. cerevisiae strains, one with high and other with moderate fermentation rate. The level of OTA in the must was 0.3mg/L. Samples were collected on different periods through the process. Progresses of the alcoholic and malolactic fermentations were monitored. Titratable and volatile acidity, pH, ethanol, sugar and SO2 concentrations were determined by standard methods. OTA analysis was done according by HPLC. The limit of detection was 0.01 ng ml-1. The OTA levels during the vinifications dropped in average about 83%. Adsorption of the toxin to the yeasts lees could occur. The type of S. cerevisiae strains used showed no effect in the toxin reduction.