Using wood for aging cheese
For centuries folks have been aging cheese on wooden boards and shelves. Primarily because it has been local and readily available.
In Jim's aging room (a cellar dug 9 feet feet down under the kitchen) he uses wood. The shelves are a combo of tight pine boards (few to no knots or resin spots) and ash. he also uses pine boards for drying boards because they will absorb excess moisture from the cheese as well as in his plastic boxes for higher moisture cheeses since they will provide a nice even humidity. All of the wood has been air dried for several seasons.
The shelf thickness (3/4") and supports are all scaled to support the cheese size and weight he makes. These are usually smaller cheeses in the range of 5-10 pounds. The shelf spacing is designed to leave space between the cheeses and also between the cheese and wall since air circulation is so important. When placed too close to the wall or other cheese mold will become more of a problem. Also Jim uses pieces of our cheese draining mat to encourage airflow between cheese when stacking but these are only for aged cheese with very firm and dry rind
Another option for increasing space when aging long aged cheese with hard rinds is the upright storage racks as shown below:
For heavier cheeses the shelves need to be substantially thicker and the support spans closer together as in the case of these 90-110 lb Beaufort cheese below
Or these equally heavy Parma's in Italy
One of the most efficient systems I have seen for transporting and aging several cheeses is to use a deeper rack that holds boards with many cheeses on each board. The boards are place in at right angles to the racks rther than parallel.
These can then be moved as a group and carried between rooms, several at a time.
Is wood Good or Bad?
This has been the aging surface of choice for centuries. The advantages seem to be the porosity of the wood and its natural character. The wood will act as a moisture reservoir, holding moisture when the cheese has excess and returning it to the cheese when low moisture prevails.
Wood also has the ability to provide a place for the unique microbes to establish themselves for reseeding the surface molds of many cheeses.
Another recently understood aspect from Ireland is that some of the coryneforms that are harbored in the wood will naturally fend off (out-compete) the Listeria that tends to grow in washed rind cheeses.
In recent times the thinking was that wood is bad because of its porosity harboring many undesirable bacteria that could not be sanitized away and the trend was that chefs and restaurants needed to get rid of the wood cutting surfaces and knife handles. The errors of their ways were quickly apparent as they found that plastic came with its own problems.
Larger scale cheese makers have gone to plastic and stainless steel surfaces, especially for the higher moisture cheeses and I do see many benefits for this. The biggest advantage being plenty of air circulation on washed rinds and mold ripened cheeses.
Some regional regulations which require smooth easily cleanable surface will not allow wood and others will allow "only hardwood" to be used in any thing that touches the cheese.
Other areas go as far as to require the boards to be held at pasteurization temperatures and times before reuse.
Many cheese makers and affineurs specifically use rough cut wood boards because these help to let air circulate beneath the cheese, and some have cut grooves across the grain to allow air to circulate under the cheese.
What kind of wood
In France folks use primarily a wood called Epicea which is the spruce tree group. I have also seen folks including Larch in this group.
Wood and especially pine and fir harvested in the summer will be wet and full of moisture, yeasts, and bacteria that will cause a cheese to age poorly. But harvested in winter this will be drier and more suitable for cheese aging. Some cheese makers such as in the caves at Roquefort will dry the wood for several season before using.
These are some of the woods I have had experience with. If you have used other and would like to comment please contact me firstname.lastname@example.org:
Spruce: is very open surface and a positive aromatic quality from the resins
Larch: is similar to spruce but not as aromatic
Pine: use clear without a lot of knots and resin
Cedar: some folks like this but it can be very aromatic and interfere with natural cheese aromas
Beech: is very tight surface slower to absorb and release moisture
Birch: is similar to beech
Ash: is good and strong and has an open grain structure for seed microbes
Oak: may be fine but is quite heavy to move when cleaning or transporting
Bamboo: is quite neutral
Not So Good
Maple: but this also can cause staining of the cheese
Walnut: will impart an off flavor and stain the cheese
Redwood: will stain the cheese
Teak: may stain and impart an incompatible flavor
Mahogany: may also cause staining and is too heavy
Exotic woods and woods that stain or leach natural resins. Many of these have been found to produce toxic resins.
Cleaning the boards and shelves
After each use or even as needed the shelves and boards need to be cleaned. The number one rule here is no detergents or cleaners. Wood is very absorbant and will absorb some of this. This is not what you want in your cheese.
Most of the cheese makers I visit use only hot water and a good brush to remove the surface debris. Some of the larger operations can also afford highe pressure washing systems or even specialized automated wash and brush systems.
... and then Sanitize
Once clean we have to pay attention to any surface bacteria and molds that are hiding on the surface. Normal sanitizers are not good to use here so what do we do. Mother Nature has the answer. What I see throughout Europe are stacks of boards drying in the sun. This is not just to remove the moisture but it is also pointed out that 'Ol Sol' has the ability to sanitize naturally with an abundance of UV. The UV will cut back the numbers of microbes on the board surface.
Shown above are the boards being exposed to the sun for drying and sanitizing
and the racks used for the boards at a small farm reblochon producer in the Savoie region of France
It will be essential to make sure that the boards have dried out well before placing cheese back on their surface.