Mutage

Mutage /ˈmjuːtᵻdʒ/ MEW-tij is a wine making technique for making sweet wines.

The typical process involves the addition of alcohol to the must so that the fermentation process is prematurely stopped. Most yeast dies when the alcohol content in their environment is raised to approximately 13-15%. By stopping the fermentation of sugars, a sweet taste of the wine is achieved. This technique is used to make port wine and other sweet wines with high alcohol content.

Two types of mutage are sometimes distinguished. A distinction being made between adding alcohol to the must before fermentation and adding during fermentation.

Reds

Whites

Other techniques for making sweet wines exist such as vendange tardive, the noble rot, various filtration techniques or early heating of the must, and adding sweet musts after fermentation.

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