Changes

* The next morning the cooled wort (~18°C) is pumped into oak or chestnut [[Barrel|barrels]].

* Spontaneous fermentation occurs in these barrels. Initial the fermentation is visibly active and may foam over out of the abrrels. A long slow fermentation and maturation with wild yeast and bacteria follows the initial visibly active fermentation. This long fermentation lasts one to three years, during which time all of the fermentable sugars and longer chain carbohydrates are consumed

===Appearance:===