Wine glossary

to neutralise (new wooden casks)
Definition:the process of neutralising a new wooden wine cask or wine container, so that it is clean before it is filled with a must or wine

This is achieved by water, steam or sterilisation. If the oak barrels are not toasted, and will eliminate the unripe "green" note (describes in German as Neuerl, or "new" taste). The same process applies to wine glasses or decanters, which are rinsed through either with water or a small measure of wine.