Wisconsin Tomme (pronounced T-oh-m as in "Home") has been the signature cheese of Creme de la Coulee Artisan Cheese for the past few years. A unique hybrid of brie and sharp cheddar, the Wisconsin Tomme was the original creation of cheesemaker Bill Anderson. The brie-like rind, developed through cave-aging at Bleu Mont Dairy, lends mushroom, cauliflower, and earthy aromas which intensify as the cheese ripens. Underneath the surface, the semi-soft interior has a flavor reminiscent of an aged cheddar or parmesan.
My Wisconsin Tomme goes through a two-step aging process, to ensure it always reaches you at the ideal stage of ripeness.
The initial cheese, which later becomes Wisconsin Tomme, is made in large batches at Specialty Cheese Company. Their vats hold about 15 - 16,000 pounds of milk, which is equal to 1744 - 1860 gallons. This yields just shy of 2000 pounds of cheese. That's a lot of cheese for a one-person operation like Creme de la Coulee to both age and market all at once! So I break it down into smaller "sub-batches", but this is only possible if we first slow down the aging process.
The day after the cheese is made, it gets vacuum-sealed in plastic "cryo-vac" bags, and goes into refrigerated cold-storage. (Note: This is how most conventional cheese is made and aged in Wisconsin.) At this point, the cheese has no rind at all, and not much flavor. It is more like a mild Colby or Monterey-Jack than like the Tomme you've come to know.
As it ages anaerobically (without oxygen) under refrigerated conditions, it starts to develop flavors like a sharp cheddar. This flavor development depends on the cultures which were added to the milk at the very start of cheese making. These bacteria initially convert the lactose into lactic acid during the first 24-48 hours. But as the cheese ages and the cultures die off, they release enzymes which slowly breakdown the protein and fat in the cheese, yielding the aged flavor enjoyed by fans of Sharp Cheddar, Parmesan, Gruyere, and other varieties of aged cheese. As you can imagine, the types and strains of bacterial cultures have a big impact on the resulting flavor!
However, the Wisconsin Tomme's aging journey doesn't end there. In order to develop a rind, the cheese must be taken out of these "cryo-vac" bags, inoculated with entirely different cultures, and allowed to cure in a cellar-like environment at Bleu Mont Dairy. These cultures are aerobic, meaning they need oxygen to grow, and so they only grow on the outside of the cheese forming the brie-like rind. They consist of a combination of yeast, mold, and bacteria which impart the mushroomy, earthy, and pungent aromas and flavors.
The tricky part of this step is that once the cheese has these aerobic cultures, it ages in a very different way. At first is has a mild mushroom flavor, but over several months evolves into a more complex earthy umami flavor that is quite delicious. However, eventually it becomes very strong and pungent, and within 6 months the cheese may be too strong for most people. There are definitely a few who enjoy this very pungent flavor, but I generally try not to let more than a couple wheels get to this "Mature" stage of ripeness.
This is why I make smaller "sub-batches" of Wisconsin Tomme. By staggering the introduction of the aerobic rind cultures, I can always have some Tomme that is at just the right stage of ripeness. Meanwhile, the anaerobic aging continues on the rest of batch still in cryovac, without a rind, leading to a more flavorful cheese for future sub-batches.