Wood plays an important role in the aging of smear-ripened (washed-rind) cheese. It regulates humidity levels on the surface of the cheese, and in addition, the biofilm that forms on it encourages the growth of smear flora. In Switzerland, the spruce logs used to manufacture cheese boards are selected with great care. They are then calibrated, cut and chamfered to produce the shape required by the cheese. The final stage is drying; either naturally or over several days in a kiln at 55–60 °C, until the board reaches a humidity level of 12–14%. This stage is very important as it reduces the risk of mould formation. Then the board must be stored in a dry, well-ventilated place until use. On taking delivery of new boards, careful attention must be paid to their storage and handling before using them for the first time. These boards have not yet developed a protective biofilm and contain very little moisture. The absence of biofilm enables the growth of undesirable flora such as moulds, while the low moisture level causes the boards to absorb moisture from the cheese. This dries out the rind and encourages the growth of a smear flora similarly contaminated with moulds. Before using boards for the first time, it is advisable to wet them thoroughly with water enriched with a surface culture or a high-quality cheese smear. Several hundred mature cheeses can be stored in a new cellar equipped with new boards to facilitate the integration of a healthy ripening flora.
