This chapter focuses on the scientific and technological aspects connected with aging on lees (AOL) of white wines. AOL technology in still wines is discussed considering its management in wood barrels and stainless steel tanks, while for sparkling wines the effects of lees are examined depending on the refermentation method. Yeast autolysis and the modifications of wine lees during aging are reviewed, considering autolysis induction mechanisms and the microbiological aspects connected with yeast autolytic capacity. The composition of wine lees is treated considering the main compounds released or developed during AOL and analyzing the most important compositional and sensory modifications induced on wine. Major chemical and microbiological problems connected with AOL are also disclosed, as well as the role of certain traditional and emerging technologies used for accelerating AOL.
