Winemaking, botrytized sweet

The high prestige and superb quality of botrytized wines has inspired many winemakers, both within and exterior to Europe, to encourage noble rot and produce botrytized sweet wines. 

The addition of thiamine is legal in several countries (EU, at a dose of 50 mg/hl) but it is rarely used to accelerate fermentation in winemaking. It effectively decreases significant ketonic acid concentrations by decarboxylation (pyruvic and a-ketoglutaric acid). Large quantities of these acids bind to sulfur dioxide in botrytized sweet wines (Section 8.4.2). 

In conclusion, each type of winemaking contains a key phase during which the decisions of the winemaker have a determining and almost irreparable effect on wine taste vatting for red wines pre-fermentation operations for dry white wines and noble rot development and picking conditions for botrytized sweet wines. 

Due to their high viscosity, these grape crops cannot be drained before pressing. They are directly transferred to the press cage by gravity or a conveyor belt. Pressing is certainly the most difficult and essential operation in botrytized sweet winemaking, and incorrect operation of the presses can sacrifice qualify. These operations in particular must be carried out slowly and delicately. 

As with dry white winemaking, overclarification can lead to large fermentation problems and increased acetic acid production. Must turbidity should not be as low as in dry white winemaking (100-200 NTU) 500-600 NTU or even a slightly higher turbidity is perfectly acceptable. Moreover, botrytized sweet wines are not subject to the same problems related to insufficient clarification as dry white wines—the development of reduction odors and vegetal tastes, oxidability, etc. 

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