A pilot tangential filter made by the Societe I D E and 4 different membranes were tested in a cooperative winery in the Gironde during the 1983 crush. The apparatus can produce, from a must or wine high in suspended solids, a liquid brillantly clear, sterile, and heat (protein) stable. However, certain membranes profoundly modified the macromolecular stucture of wines (polysaccharides and polyphenols) and the organoleptic character of red wines.
