WINETECH Technical Yearbook 2019

THE EFFICIENCY OF FILTRATION PRIOR TO BOTTLING

CHARL THERON: Private consultant KEYWORDS: Filtration, bottling. DECEMBER 2019

Filtration is a complex process. The choice made by winemakers regarding filtration requires background knowledge to ensure that the correct filtration is used for a specific purpose. This is especially important prior to the bottling of wine. The efficiency of liquid filters is indicated by its ß-value (beta value). The ß-test measures the ability of a filter to remove particles of a certain size from the liquid. It is calculated by dividing the number of specific particles entering the filter by the number of the same particles leaving the filter. Mathematically it can be formulated as follows: ß = Particles prior to filtration ÷ Particles after filtration The ß-ratio can be used as follows to determine the efficiency of filtration: (ß – 1 ÷ ß) x 100 = Efficiency Sterile filtration is a requirement prior to the bottling of wine to prevent potential secondary fermentation and physical precipitations.

Sheet filters are one of the most common filters.