When it comes to fish, fresh isn’t necessarily always best. Counterintuitive as it may sound, fish that has been properly aged for a few days actually tastes better. You don’t want the catch of the day — you want the catch of last week. And ideally, you want it to be dry-aged. “Fresh fish is boring, bland, and crunchy,” says chef Jay Huang of Austin Japanese restaurant Lucky Robot.
Huang claims to be the first chef to bring dry-aged fish to Texas. The centuries-old method is rooted in Japan, and practiced throughout the world, though you may not have heard of it yet, as it’s still relatively new to the United States. But make no mistake, dry-aging fish is a time-honored technique, and the secret to delicious, tender seafood.
The burgeoning popularity of dry-aging fish is partly driven by the success of the Australian restaurant Fish Butchery (and their cookbook), and, in part, by technological advancements that help facilitate the process. And, thanks to Huang, you can now get it in Texas.
The phrase “dry-aged fish” might conjure images of smoked salmon or pickled herring, but it’s something different entirely, created without smoke or any additives — just the fish, air, and time.
Historically, itamae (sushi chefs) would age fillets of fish between sheets of kombu for up to 24 hours, an ancient process known as kombujime. This is the foundation of modern dry-aging techniques, though chefs now have access to state-of-the-art technology that allows them to age the protein for days, and even weeks.
Dry-aging blurs the line between science and art form. As is the case with steak, dry-aging fish enhances flavor and makes for a better eating experience. “Time and enzymatic action relax the muscles and transform amino acids into flavor molecules,” Huang says. After being caught and killed, fish become stiff with rigor mortis, making them tough and unpleasant to eat. The enzymatic action breaks down the protein to make it softer and more delicate. The resulting molecules are responsible for creating the prized umami taste believed to enhance flavor.
The true magic, however, is in the dehydration. Fish are hung in temperature-controlled cabinets, sometimes called dryers, as part of the aging process — similar to how sides of beef are hung in large coolers. Over the course of several days, the moisture within the fish slowly evaporates, concentrating its natural flavor and revealing new depths and subtleties of taste. Basically, it gets better.
“Some of the raw preparations we do, you can taste this natural flavor in the fish that we didn’t even know was there,” says chef Michael Nelson of GW Fins, an upscale New Orleans seafood restaurant that has recently started serving dry-aged fish. “When you have fresh red snapper, raw and right out of the water, it doesn’t have much taste at all. But if you hang it in the dryer for five days, the texture is way better and, suddenly, it has flavor.”
Proper dry-aging requires patience, but also precision. Each fish must be as fresh as possible, and practically pristine. Even the smallest bruise can ruin the process. “If you put something in the cooler that isn’t [pristine], the results will be horrible,” Nelson says.
One method that’s known to preserve the quality of fish is called ikejime. The traditional Japanese form of butchery is favored for fish destined to be dry-aged because it quickly kills the fish without struggle or bruising. The process is believed to prevent the buildup of lactic acid, ammonia, and other stress hormones that negatively affect the fish’s taste. Huang works with Minamoto Foods, who utilize the ikejime technique and teach it to other Texas fishermen. Huang also introduced Gulf of Maine Sashimi and the Gulf of Maine Institute to this technique, which the companies use on many of their catches to produce a better product.
In the kitchen, Huang uses a Japanese knife technique called sukibiki, which descales the fish without breaking the skin. “This is absolutely necessary for dry-aging. This creates a natural semipermeable membrane that allows for gentle dehydration and flavor concentration.” Instead of using the traditional kombujime method, the fish is aged within its own skin, which is both more sustainable and creates new and unique textures. The process dries out the skin which allows for a “thin, tulle-like crunch” to develop, says Huang. This works even on tough skins, like grouper, which are normally considered inedible.
The technique is undoubtedly crucial to a well-aged fish, but technology facilitates the process. “The thing you learn really quickly is that every fish reacts differently, and the humidity level [within the dryers] can be a huge factor,” Nelson says. New and affordable drying cabinets are capable of extremely precise measurements, making the process easier than ever. Instead of being subject to weather fluctuations, chefs can create precise temperature and humidity conditions. For example, Huang keeps his drying cabinets, sometimes called a cooler or a dehydrator, at a strict 0.8 degrees Celsius (just under 33.5 degrees Fahrenheit) and 82 percent humidity, a nearly impossible feat through traditional methods.
Yet even with the latest technology, each fish is unique and requires constant monitoring. Age it for too short a time, and the fish remains flavorless and tough. Leave it too long, and it turns to jerky — which, while safe to eat, isn’t to everyone’s taste. Huang once aged a Big Glory Bay king salmon for 45 days, and remembers it smelling like a wheel of Epoisses cheese, with notes of brie rind and wet hay. “It was a fun experiment, but absolutely aged too far.”
Huang describes fish the way a sommelier might describe the notes of a wine. He believes highlighting familiar flavor profiles makes the product more approachable to the uninitiated. Through trial and error, Huang has learned to age king salmon between seven and 14 days for the “perfect buttery texture” with “flavors of whipped creme fraiche potatoes.” After 22 days, the fish becomes “creamy, like an avocado, with a slight jerky-like bite and flavors of aged cheddar.” Lucky Robot’s current menu features a mix of seasonal and evergreen dry-aged fish options, from salmon to tuna to pompano to Spanish mackerel.
Nelson believes it will become a regular fixture soon enough. “It’s too exciting not to become more common,” he says. Huang adds: “Chefs are always striving for techniques and processes that will maximize flavor.” Several have already reached out to him to learn about the process.
While chefs have taken to dry-aged fish for the flavor, customers are also developing an appreciation for the craft, says Huang. “We have had nothing but wonderful, positive feedback,” Huang explains. “Customers love interacting with the case and seeing the offerings. When the sushi finally hits the table, they are blown away by the difference.”
- All Coverage of Lucky Robot [EATX]