TIMBERS USED BY BREWERS

The essentials in timbers for vats and casks include impermeability to liquids, resistance to fungal attack, freedom from taint and minimal change in size on wetting and drying; of these, Impermeability is of outstanding importance, and reaches a high level in the white oaks. European and American sources of oak have recently been supplemented by supplies from Persia, though some samples from this source have proved unsound and cases have been known of beer‐tainting following the growth of Stereum subpileatum; steam treatment of heads and staves should remove danger from this fungus. Laminated casks would probably be satisfactory if the laminations were thick enough; metal casks have advantages and disadvantages, as have also metal‐lined wooden casks. In timbers of building construction, every precaution should be taken against favouring the development of dry‐rot. Effective treatments are now available to combat wood‐boring insects.