WINETECH Technical Yearbook 2021

them. An ultraviolet lamp is placed for three minutes in the clean barrel and no steam or ozone generation and rinsing are required after sanitation. From a safety point of view it is also better, because steam burning and ozone exposure cannot occur. From a sustainability viewpoint, less energy and water are required. At some stage it must be decided whether it is better to rather install an automated cleaning and sanitation system for barrels. No personal supervision is then required and it can usually be combined with the filling or emptying of barrels. If the cleaning and sanitation of barrels are not effectively done regularly, the

precipitation of cream of tartar can be as such that it cannot be removed by standard methods. The sand blasting of the precipitate with dry ice can then be used. It can also remove the blisters, formed during steam sanitation. This treatment is usually recommended after three years and the active lifetime of the barrel can be extended with a year. In order to ensure that any cleaning process is executed effectively, one of the barrel heads should be removed to inspect the inside (Starr, 2021). REFERENCE Starr, A., 2021. Barrel cleaning and sanitizing systems. Wine Business Monthly , March 2021: 48-56.

precipitates. Different products exist with pressure between 6 300 to 7 700 kPa and a water consumption 17 to 28 litres per minute. Some of these can also suck the lees and cream of tartar from the barrel after the cleaning process. Micro-organisms can only be killed if the surface is clean. Steam and ozonated water are the two best known sanitisers, but ultra-violet is also becoming more readily available commercially. When steam condensates, its latent heat is liberated. Increasing dryness of the steam will increase the latent heat, which will also increase its sanitation ability. It is also recommended that barrels are closed

with bungs for five minutes after it was steamed for three to five minutes. Due to the cooling a partial vacuum is then created in the barrel. As a result of this water and remaining wine are sucked from the barrel pores, which can be removed from the barrel by a 30 seconds rinsing process. Steam generators can be mobile and electrically or diesel driven. Ozone is microbiologically just as effective as steam, but has a surficial action and is therefore not so effective for the sanitation of barrel pores. It does however require less energy than steam and less labour is also required, because rinsing actions are unnecessary after sanitation. Ultraviolet radiation inactivates micro-organisms and also kills

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