Bentonite is a clay that is used to remove proteins from the wine. These proteins are unwanted because they can cause a protein veil in the wine. Bentonite is a mixture of different minerals in which the mineral montmorillonite ensures the adsorption of proteins and the absorption of water. The proteins bind to the montmorillonite and sink to the bottom of the tank. Bentonite can be added before, during or after the alcoholic fermentation. Unfortunately, montmorillonite also binds aromas and colorants and can therefore have an adverse effect on the quality of the wine.
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