The period of fermentation and aging (or lagering) which follows primary fermentation. During secondary fermentation, the remaining fermentable sugars are fermented and the beer or wine begins to clarify and age. Secondary fermentation must be complete before the wine or beer is packaged.
Fermentation that takes place in a closed container, usually for several weeks to several months immediately following primary fermentation. Secondary fermentation naturally carbonates the beer and matures its flavour.
See Malolactic Fermentation