Effect of different sanitizers against Zygosaccharomyces rouxii.

Microbial contamination is a problem in food industry. The effects produced by the metabolic activity of yeasts are diverse. If they are found in high numbers it might affect the organoleptic quality of the product. Zygosaccharomyces is the most frequent contaminant genus in sweetened juices that are not properly processed and stored. The aim of this work was to compare the action of five commercial sanitizers against isolates of Z. rouxii and to determine appropriate concentrations and time of action for the inactivation. Peracetic acid, monochloramine, iodophor and quaternary ammonium compounds were evaluated on different surfaces (stainless steel, plastic and glass) at room temperature for 30 and 60 s. It was possible to achieve a 99.99 of death Efficiency corresponding to 4 log10 of reduction for a contact time of 60 s for 0.5% (v/v) of peracetic acid, monochloramines and 0.5% (w/v) of iodophors, 1% for compound with a base of 8% (v/v) of benzyl chloride and 7.5% (v/v) of glutaraldehyde and 5% for sodium hypochlorite (55 g/L active compound). Stainless steel was successfully sanitized with all the compounds tested, and then it would be the most appropriate for the food industry because this material is also highly resistant to abrasion, to impact and to different chemical treatments. In view of the great variety of sanitizing products, the selection of the best sanitizer will depend on efficiency, safety and cost.