Bucatini With Fermented Whey, Maitake, and Black Truffle

Bucatini with Fermented Whey, Maitake,

and Black Truffle

I’ve been pretty busy since my last post, starting as sous chef at a Pittsburgh neighborhood European wine bar called The Vandal. And things have been going really good. The team is very friendly and the scratch-made food that we put out is, in my opinion, excellent. The menu often changes from week to week, and sometimes even day to day. Things can move pretty quickly, which has given me the opportunity to learn a lot, and fast. 

Starting in November, I took the initiative to build a fermentation program. At that point, I wasn’t quite sure in what direction I wanted to take it. I started making batches of koji. I figured having koji around could help fill in the gaps, possibly giving us ways to further utilize ingredients we already had; not to mention helping with our bottom line by repurposing “waste” destined for the landfill. 

The first ferment I made was a concentrated whey shio koji. Shio koji is a fermented, savory slurry that can be used to brine meats and spike sauces. It is made by blending equal parts koji and water and salting to 5% of the total weight. It can be used right away or left to undergo a secondary ferment at ambient temperatures for a week, or more.

One day, Bucky, the executive chef, was reducing all of the whey accumulated from making several pounds of ricotta, when I was struck by an idea: I would replace the water in the shio koji with the concentrated whey. The day I blended the 3 ingredients together, the concentrated whey shio koji tasted very sharp. After 15 days of ambient fermentation, the sharpness remained, while a striking blue cheese flavor had developed. I transferred the fermented brine to the fridge in order to allow it to continue fermenting at a slower rate, all while racking my brain, trying to come up with an interesting way to use it for a dish.

A month passes by. All of a sudden, we find ourselves sitting on a mountain of gourmet mushroom trimmings. For weeks we plowed through cases and cases of maitakes and king trumpets, as well as buttons, shiitakes, and oysters. We had 2 mushroom heavy dishes on the menu; one was a mushroom fricassee, and the other, a beautiful, more fully realized version of my gnudi en brodo, garnished with roasted gourmet mushrooms, braised leeks, and black truffles. Some of that mushroom trim made it into stock, but a lot of it did not. 

I thought back to a recipe I once spied from The Noma Guide To Fermentation for fermented mushrooms and their juice. The process is quite simple: freeze the mushrooms in order to break their cell walls, then salt to 2% of the weight and let ferment for a week. What you’re left with are two products: the mushrooms themselves, and all of their leeched juice. The juice is then clarified through freezing and thawing. The timing was perfect to give their recipe a try. I froze pounds of gourmet mushroom trim, then salted them to 2% of their weight. After 5 or 6 days, the flavor of the mushrooms and mushroom juice was intense, akin to truffles I would say. I clarified the juice and chucked it in the freezer for another day.

Last week we retired the gnudi en brodo. It had a great run, one longer than normal for how quickly we change items; and I feel pretty confident when I write that it was a testament to it’s positive reception and overall success. It was a lot of work and a wonderful learning experience for me to tackle that project on my own. That being said, I wouldn’t have been able to do it if not for the support and encouragement of my team.

With the gnudi retired, it was time for a new vegetarian entree to take the stage. Joey Hilty, my boss and co-owner of the Vandal, suggested bucatini, perhaps dressed in a mushroom velouté. Velouté is one of the five mother sauces of French cuisine. Think of it as a building block to making a host of other sauces. Velouté is made by whisking stock into a roux and reducing it to a smooth, velvety, sauce. Finally, I thought, an interesting application for the first and last ferment I made this year at The Vandal! 

I spiked that velouté with a splash of the lacto-fermented mushroom juice and a spoonful of the concentrated whey shio koji. Needless to say, the flavor profile became complex, but thankfully not overly so. The lacto-fermented mushroom juice lended acidity and earthy funk, while the concentrated whey shio koji brought a cheesy, umami punch to your palate, leaving you salivating for more. A sauce like that tossed together with fresh pasta and gourmet mushrooms; what more could you ask for? Perhaps some shaved black truffle? Call it a dish!

It was a great feeling for me to finally be able to put some ferments into use at work. Even though the fermented components were non-essential—meaning that I believe the dish would have been great to serve without them—I can’t help but feel proud of transforming ingredients that would have otherwise been at the end of their life into something new and interesting, not to mention a little challenging.

Some things to note: The recipes for the concentrated whey shio koji and the lacto-fermented maitake mushrooms and juice can be scaled up or down as needed. Simply know that for the shio koji, you will need to salt at 4-5% of the total weight. For the lacto-fermented mushrooms, salt at 2% of the weight. You can use whatever mushrooms you have on hand as well. Lastly, I have included a new recipe for making koji, having had the chance to make multiple batches and fine tune the process. My new standard for grain is Carolina Gold rice, which I toast first, and then cook like risotto. This gives me a perfectly al dente rice that the koji simply loves to digest. No more mushy overcooked jasmine for me!

For the pasta (serves 4-5):

• Bucatini pasta, cooked al-dente
• 1 1/2 tablespoon unsalted butter or koji butter
• Several florets of maitake mushrooms
• Mushroom and koji velouté (see below), to dress
• Parmigiano-Reggiano, freshly grated, to garnish
• Toasted breadcrumb, to garnish
• Chives, finely chopped, to garnish
• Black truffle, grated or shaved, to garnish

For the mushroom and koji velouté :

• 3 tablespoon unsalted butter or koji butter
• 3 tablespoon all-purpose flour
• 2 cups approx. mushroom stock
• 1 tablespoon concentrated whey shio koji
• 1-2 teaspoon lacto-fermented maitake juice

For the concentrated whey shio koji:

• 1kg toasted Carolina Gold rice koji
• 1kg concentrated whey
• 50g salt
• Time

For the lacto-fermented maitakes and juice:

• 1kg maitake mushrooms and/or trim
• 20g salt
• Time

To make the toasted Carolina gold rice koji: Bring a pot of water to a simmer. Meanwhile, toast 1 quart of Carolina Gold rice in a large saute pan over medium-high heat until brown but not burnt, about 10-15 minutes. Cover the rice with the simmering water (it may sputter, so take care) and turn the heat down to medium-low. Continue to cook, adding simmering water as needed, until the rice is cooked al-dente, about 20 minutes. Spread out the al-dente rice on a baking sheet and let cool to 90F. Inoculate the cooled rice with koji spores and mix thoroughly with clean hands. Transfer the inoculated rice to a fermentation chamber (I use a fish tub wrapped in plastic with some finger-sized holes poked in the top) and incubate at 90F for up to 48 hours. You may need to stir your koji after 24 hours if your koji temps breach 105F. The koji generates its own heat and will die at temperatures above 110F. Stirring also promotes mycelium growth. Once finished, the rice should be completely matted in fuzzy white mycelium. Let cool completely. The koji will last for a few weeks in the refrigerator or several months in the freezer. 

To make the concentrated whey shio koji: Bring whey up to a simmer and reduce by about half. This will enhance the punchy, umami flavors locked in that liquid—kind of like whey in 3D. Let cool completely. The whey can be reduced a few days in advance. Blend together equal parts toasted Carolina Gold rice koji and whey, plus 5% of the total weight in salt. Note: if your concentrated whey tastes especially salty, salt the koji and whey to 4% of the total weight. Transfer the contents to a sterilized mason jar and secure the lid with paper towel/kitchen cloth and a rubber band. You can use it right away but the flavor will improve with age. I let my concentrated whey shio koji ferment at room temperature for 15 days before transferring it to the fridge, at which point it began to taste like blue cheese from the 5th dimension. It has been fermenting more slowly in the fridge since, for an additional month.

To make the lacto-fermented maitakes and juice: Arrange the mushrooms and/or trim on a sheet tray and freeze for 24 hours. This will break down the mushroom’s cell walls. Remove from the freezer and salt to 2% of the weight. Transfer to vacuum sealed bags. If you do not have a vacuum sealer, place the salted mushrooms in sterilized jars with weight pressing down on them. A Ziploc bag filled with water works well. Leave the jar open a crack to allow gas to escape. After 5 days, the mushrooms will have released their funky, now fermented, juice. 

Strain the solids out from the liquid and freeze the liquid for 24 hours. Clarify the liquid by setting the frozen block of juice over a fine strainer in a bowl. The pure liquid will melt while the impurities will stay trapped in the block. Allow the pure liquid to thaw through for a couple of hours. The clarified liquid and the lacto-fermented mushrooms have a short shelf life; use within a week or simply keep frozen until ready to use.

To make the mushroom and koji velouté: Bring the mushroom stock to a simmer. Meanwhile, heat 3 tablespoons of unsalted butter in a separate pot over medium high heat. Have your flour and a whisk at the ready. Once the butter has foamed, sprinkle in the flour a bit at a time, whisking constantly all the while, until a blonde roux has formed. Let this roux heat through for a few minutes. Stream in the mushroom stock a few spoonfuls at a time and continue whisking. Allow the mixture to return to a boil before adding more stock. Continue this process until all of the stock is used up. Gently reduce the velouté until you’re left with a smooth, velvety sauce that coats the back of a spoon. Remove from the heat and stir in the lacto-fermented maitake juice and the concentrated whey shio koji. Add more of those to taste, if you prefer. The velouté will last in the fridge for up to a week.

To make the pasta: Bring a large pot of heavily salted water to a boil. Meanwhile, heat 1 1/2 tablespoons of butter in a sauté pan. Lightly sauté the maitake florets. Cook the bucatini until al dente and then transfer it to the pan with the butter and mushrooms. Toss in enough mushroom and koji velouté to generously coat and heat through, mixing everything together thoroughly.

To plate, place the pasta and mushrooms in the center of a plate. Shave fresh Parmigiano-Reggiano overtop. Follow with breadcrumbs, chives, and truffle. Serve immediately.