Once you start making cheese, you’ll quickly realize you’re left with a large quantity of whey—so much you’ll be loath to just pour the yellowish liquid down the drain. Fortunately, whey has many uses. You probably already consume more whey than you realize: it’s popular in protein powders, weight-loss beverages, and even infant formula. Cheese makers have long known the value of this by-product and use it to make more cheese, like ricotta and my favorite gjetost.
Whey is considered sweet or acidic. Hard cheese and Fresh Yogurt give you sweet whey; Lemon Cheese gives you acid whey. Some sources prefer sweet whey for most uses, but I love tangy flavors. I use the whey from Lemon Cheese as a cooking liquid for rice, a stock substitute in soups, and a cheese sauce replacement for soups and pasta.
Whey sauce is not for the lactose intolerant. Lactose hangs out in whey when you drain your curds to make them into cheese. That’s one reason some people who struggle with lactose can eat harder cheeses: less moisture means less whey. But those with lactose issues may still be able to use some whey. Fermentation reduces the lactose even in whey, so if you can eat yogurt, make a fresh batch, drain it, and try the separated yogurt whey as a sauce base. If you have a more serious lactose intolerance, you’ll be happier saucing your pasta with a brown butter–Parmesan sauce or a dairy-free roasted tomato sauce.
reserved whey from making 1-1/2 to 2 pounds of Lemon Cheese or a hard cheese
Pour the whey into a large, heavy-bottom pot and bring it to a boil, uncovered, over direct heat. Stir often and monitor the pot carefully as it approaches a boil. When the whey boils and foam forms on the surface, skim off the foam with a perforated or slotted spoon and place it in a small bowl. Keep skimming until most of the foam is gone and the whey boils in large bubbles. Cover the skimmed foam and temporarily place it in the fridge.
Reduce the heat to keep the uncovered pot of whey bubbling steadily, and let it simmer slowly for 2–3 hours, until the whey is reduced to about 2 cups. Stir occasionally to prevent sticking.
When you reach the desired reduction, stir the reserved foam into the thickened whey. Pour the hot whey sauce into a 1-quart or larger nonreactive bowl or measuring cup, and puree with an immersion blender for at least 1 minute. Use immediately (see below), or store in a lidded container in the refrigerator for up to 1 week. Makes about 2 cups.
Tips & Tricks
- Fresh whey is key when reducing to a sauce or making more cheese. The fresher the whey, the sweeter the result, even if you use whey left from making an acid-added, heat-coagulated variety like Lemon Cheese.
- Cheese whey is made up of milk sugar, minerals, and protein. By cooking it down over high heat, you’re letting the protein coagulate, forming more cheese.
- High heat also lets the protein form a skin that traps water vapor—hence the tendency to boil over. A similar process happens when boiling jam. In both cases, skim off the foam to avoid a giant, smelly mess.
- Pureeing keeps your sauce smooth and creamy; it tends to get gritty otherwise. You’re most likely to notice the texture if you pour the sauce straight onto a bowl of pasta.
- I’m a huge fan of immersion blenders; pouring anything boiling hot into a blender and then slapping on a lid terrifies me. If you must use a standard blender, hold down the lid with a potholder while you work to prevent it from flying off.
- Whey sauce adds amazing flavor and texture to baked pasta (see below). It’s also delicious in Broccoli Cheese Soup and Boozy Potato Chowder: simply replace the milk and cheese in each recipe with whey sauce, and then stir in a bit of grated cheese at the end or sprinkling it on top for bonus flavor.
- Whey kept up to a week still has many uses. Substitute it for water in Sourdough Pizza Dough, Sourdough Pita Bread, or other baked goods. Use it instead of stock in Hearty Corn Chowder or a creamy soup. Or use it when cooking rice for under a curry or stir-fry.
Twice as Tasty
I grew up on real macaroni and cheese. I’m not talking Kraft dinner; I’m talking elbow pasta mixed with a béchamel cheese sauce and topped with freshly grated Cheddar that you baked in the oven until it was hot and bubbly and the cheese topping formed a crust you could pull off and sneakily eat like a chip. That’s how much my mom loves us.
Actually, the sign of how much she loves us is the short ingredient list of her recipe. My mom is a fan of mustard’s spice, extra-sharp Cheddar’s bite, and garlic’s zing, all flavors I now adore but had to grow into (my dad still hasn’t grown into such flavors). So the dish of my childhood was simple: pasta, butter, flour, salt and pepper, milk, and medium Cheddar. It’s still a kid favorite (drop me an email if you want the recipe), but a few years back I upgraded mom’s version to one that packs more punch. Then I started making cheese and found myself swapping out béchamel for whey sauce. I’ve never eaten a cheesier-tasting version.
Cheesiest Mac and Cheese
6 tablespoons butter
2 cloves garlic, minced
1 teaspoon dry mustard
1/4 teaspoon smoked chili paste or siracha
6 tablespoons unbleached flour
1 cup Vegetable Stock
2 cups Whey Sauce
salt and freshly ground pepper to taste
4 ounces extra-sharp Cheddar, grated (about 1 cup when grated)
In a large pot, cook the pasta al dente according to package directions. Drain into a colander and then rinse with cold water until it stops cooking. Let the pasta drain completely while you prepare the sauce.
Prepare a roux by melting the butter in a large saucepan. Add the garlic, mustard, and chili paste and cook over medium heat for about 30 seconds. Add the flour and cook, stirring constantly, for about 1 minute, until golden.
Whisk in the stock, adding it in a slow stream that is absorbed before you pour in more. Allow it to simmer as you whisk, with large bubbles forming on the surface as the mixture thickens. Slowly pour in the whey sauce in the same manner, continuing to whisk as you cook it for 5–8 minutes, until the mixture forms a somewhat thicker sauce. Season with salt and pepper to taste, and then remove from the heat.
Fold the pasta into the sauce, stirring to break up any clumps. Pour the sauced pasta into a 9- by 13-inch baking pan and sprinkle with the grated cheese. Bake at 400°F for 25–30 minutes, until the topping is golden brown and the dish bubbles at the edges. Cool for 10 minutes before serving. Serves 6–8.
Tips & Tricks
- This recipe combines all of the goodness of my childhood version, with its baked cheese topping and rich sauce, and my grownup taste for garlic, mustard, and smoked chili paste. It’s so rich that I cut it with flavorful homemade stock.
- This batch should fit easily in a 9- by 13-inch baking pan, but larger pasta shapes may cook better if split into two pans or with a rimmed baking sheet placed on a lower oven rack to catch drips.
- No whey? No worries: you can still make this recipe. One way would be to replace the Whey Sauce with 2 cups of milk, stirring it in slowly until thickened, and then stirring in 2 cups (8 ounces) of grated Cheddar. A better way would be to take a Fraternal Twins: Lemon Cheese and Yogurt workshop—locally or as part of next month’s road trip—and learn how to make an easy cheese that will leave you with plenty of whey.