Wine Pre Filters
The fundamental purpose of wine pre-filtration is to limit the cost of final filtration by minimizing the contaminants that can reduce the working life of the final filter. The pre-filter should be capable of removing particles left over from upstream processing (crystals, DE, fining agents), removing colloids and reducing the typical wine spoilage organisms like yeast and bacteria in order to extend the life of the final membrane filters.
A wine pre-filter should have a high dirt holding capacity, be easily regenerated in-situ and inert to the properties of wine. It is recommended to install a wine pre-filter with an absolute particulate rating of 0.8 to 1 micron directly upstream of the final filter to extend the life of the final filter (an absolute filter is one with a removal efficiency of greater than β-5000).
Given that a wine pre-filter is typically installed in-line directly upstream of the final filters and filling machine, it must be able to withstand the same sanitization and cleaning regimes as the final filter and possibly the filler itself.