The Concept of Clarity and Colloidal Phenomena

Clarity is an essential qnality reqnired by consumers, especially for white wines in clear glass bottles. Particles in suspension, either in forming a haze or dispersed through the liquid, not only spoil the presentation but usually also affect the flavor. 

New wine has a very high particle content, consisting of yeast lees and other grape debris. Clarity is achieved by gradual settling, followed by racking to eliminate the solids. Other, more rapid, processes (filtration and centrifugation) may also be used. 

Wine must not only be clear at the time of bottling but also retain its clarity during aging 

Handbook of Enology Volume 2 The Chemistry of Wine and Stabilization and Treatments P. Ribereau-Gayon, Y. Glories, A. Maujean and D. Dubourdieu 2006 John Wiley Sons, Ltd 

Nowadays, the only normally acceptable deposit is red coloring matter in old wines. Sediment should not appear until the wine is four or five years old, and then only in small quantities. It should be easy to eliminate by decanting. However, umeasonable consumer demands may sometimes necessitate treatments that enologists would prefer to avoid. 

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