Name (also silicic acid hydrosol) for colloids, i.e. finely distributed solutions of silicic acid (silicon dioxide) in water. The name is composed of Kiesel (for silicic acid) and Sol (synonym for colloid). The substance is negatively charged and therefore attracts positively charged substances. It has a high adsorption capacity and is used for degumming grape must and fining wine. Silica sol is considered a classic agent for settling yeasts, as well as for removing other agents such as activated carbon, bentonite or copper sulphate. If negatively charged substances are also to be removed, this is done in combination with positively charged, protein-containing fining agents such as gelatine (silica sol gelatine fining). A chemically related substance is diatomaceous earth, which is also used in winemaking.
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Thomas Götz
Weinberater, Weinblogger und Journalist; Schwendi