Overnight cultures of individual yeast (25 °C, 24 h) and bacteria
(30 °C, 24 h) strains were harvested by centrifugation (3000 g, 4 °C,
15 min). The supernatants were discarded and cells in the pellets
were resuspended in Maximum Recovery Diluent (MRD). The washing
step was repeated twice. Preliminary experiments showed that
OTA reduction was in the range of 5 to 15% when bacteria and yeasts
were inoculated individually (data not shown). Moreover, considering
that in most of the cases, cultures, either indigenous or exogenously
added (i.e., protective cultures), consist of more than one
species, the selected bacteria and yeasts were studied in composites