WINETECH Technical Yearbook 2021

PRACTICAL IN THE CELLAR | SEPTEMBER 2021

THE CLEANING AND SEQUENTIAL SANITATION of cellars and equipment are essential to maintain the required cellar hygiene. Cellar hygiene is indispensable to ensure that the spoilage of wine is prevented. Ozone (O 3 ) has already long been used as sanitiser in wine cellars. It destroys all bacteria, viruses, yeasts, moulds, enzymes, biofilms, microbial membranes and spores. Micro-organisms can also not develop resistance towards it. It has a half-life of several hours in dry air, but in water it varies from immediate to several hours depending on different factors like pH, temperature and pressure. The ozone molecule consists of three oxygen (O) atoms. It is formed by the ultraviolet irradiation of sunlight and the oxygen in the atmosphere. Its concentration on the global surface is 0,01 to 0,05 ppm, but as a result of air pollution it can be increased. It smells like a diluted chlorine solution. In cellars it is mainly used for the sanitation of tanks, barrels, equipment and surfaces. A 2,5 ppm ozonated water solution is for example used for two minutes for the sanitation of barrels, after the barrels have been cleaned with warm water. For seriously contaminated barrels, a five- minute contact period is however required. Ozone also limits the build-up of organic

O 3 .

The advantages and disadvantages of ozone as sanitation agent

CHARL THERON: Private consultant KEYWORDS: Cellar hygiene, ozone sanitation.

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