What is autolysis?

• A. Gradual breakdown of yeast, desirable in sparkling wine production
• B. Fermentation of sugars to alcohol
• C. Oxidation
• D. Stabilization of proteins

Answer: (A)

Autolysis is the gradual breakdown of yeast cells after fermentation, driven by enzymes released as the cells die. In sparkling wine production, especially when a wine ages on the lees (the spent yeast cells), autolysis releases compounds like amino acids, peptides, and mannoproteins. These substances contribute to bakery aromas (brioche, bread) and a creamier, fuller mouthfeel, adding complexity and texture that are highly desirable in sparkling wines.

The other descriptions don’t fit autolysis: fermentation of sugars to alcohol is the yeast consuming sugar during primary fermentation, oxidation is the reaction with oxygen that can cause off-flavors, and stabilization of proteins is a separate process used to prevent haze.