Polysaccharides from Botrytis cinerea

Table 3.6. Polysaccharide content of juice from healthy grapes and grapes affected by Botrytis cinerea (mg/1) (Dubourdieu, 1978)...

Another classic example of natural protective colloids is that of wines made from grapes affected by rot. Botrytis cinerea secretes a polysaccharide (/i-glucane) that is largely responsible for the difficulty of clarifying these wines, especially by filtration (Section 11.5.2). 

Wines made from grapes affected by rot are also difficult to clarify due to highly clogging colloids. It has been known for many years that Botrytis cinerea secretes a colloid of this type into grapes and that the resulting wines are particularly difficult to clarify by filtration. The colloid in question is a polysaccharide that has been known in winemaking for many years. It belongs to the family of dextranes... 

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