the sugars in the malt dissolve and these are drawn off through the bottom of the mash tun. The resulting liquid is called 'wort'. This process is normally carried out three times with the water temperature being increased each time to extract the maximum amount of sugar. Only wort from the first two times is used. The third lot is put back into the next batch of new grist. Any residue, such as husks, is called 'draff'. This is collected and used in the production of farm feed.