Lees are wastes generated during fermentation and aging processes of wine, cider and beer industries.
Lees must be conveniently treated to avoid uncontrolled dumping which causes environmental problems.
The recovery or transformation of lees components into high value-added compounds is recommendable.
Lees are an endless sustainable source of nutrients that can be exploited in the biotechnological industry.
Lees are promising supplements similar to yeast extract or corn steep liquor for formulating economic culture media.
Lees are the wastes generated during the fermentation and aging processes of different industrial activities concerning alcoholic drinks such as wine, cider and beer. They must be conveniently treated to avoid uncontrolled dumping which causes environmental problems due to their high content of phenols, pesticides, heavy metals, and considerable concentrations of nitrogen, phosphate and potassium as well as high organic content. The companies involved must seek alternative environmental and economic physicochemical and biological treatments for their revalorization consisting in the recovery or transformation of the components of the lees into high value-added compounds. After describing the composition of lees and market of wine, beer and cider industries in Spain, this work aims to review the recent applications of wine, beer and cider lees reported in literature, with special attention to the use of lees as an endless sustainable source of nutrients and the production of yeast extract by autolysis or cell disruption. Lees and/or yeast extract can be used as nutritional supplements with potential exploitation in the biotechnological industry for the production of natural compounds such as xylitol, organic acids, and biosurfactants, among others.
Corresponding author at: Department of Chemical Engineering, Faculty of Sciences, University of Vigo (Campus Ourense), As Lagoas s/n, 32004 Ourense, Spain.