Sanitation and CIP Disinfection

Organisms such as Brettanomyces, Dekker, or Lactobacilli produce odor and flavor during aging. High level contamination of barrels causes the wine to be bitter, mousy, metallic, or taste of manure or plastic. Traditional practices to deal with these problems include destroying contaminated barrels or treating barrels; however, some treatments can strip out oak essence.

Barrels can be sanitized with ozone without changing or tainting the wood.

Ozone Sanitation Two-Step Process

• Hot water rinse to clean barrels, dissolve tartrates, and open wood pores for ozone penetration
• Cool rinse with ozonated water to sanitize and shrink wood pores

Barrel type, barrel age, and level of microbial contamination affect the concentration of dissolved ozone necessary in the rinse and the rinse time necessary. Rinse time can range from 2.5 minutes to 10 minutes. Mazzei GDT™ Process technology eliminates ozone off-gas concerns when sanitizing barrels.

Studies done at California State University, Fresno show the benefits of using ozone for sanitation of oak barrels. Infected oak exposed to 1 mg/L ozone concentration for 2.5 to 10 minutes resulted in significant reduction in B. bruxellensis population as compared to 154º F water for 20 minutes. Another study stated that ozone concentrations from1 mg/L to10 mg/L used on oak had no significant effect on volatile aromatic compounds in the oak — oak essence, including vanilla, smoky, and toasty oak notes remained.