Abstract: A sanitary membrane cartridge for use in reverse osmosis filtering includes an outer housing, a central core tube, and a membrane leaf wound around the central core tube to form a cylindrical filter. The cartridge further includes a sealant layer disposed around the cylindrical filter to form a sealed filter, the sealed filter disposed within the housing. The sealant layer preferably has a surface roughness value, Ra, ranging from about 0.38 ?m to about 0.82 ?m. The cartridge further includes a brine seal, disposed between the sealant layer and the housing, having one or more notches formed on an outer diameter of the brine seal such that the feed flow through the notches allows bypass flow, between the sealant layer and the housing, of 1% to 25% of a total feed flow through the sealed filter.