For years dry aging was the domain of steakhouse coolers where slabs of beef slowly transformed into richer, more tender cuts. But in recent years, another protein has entered the cabinet: fish.
“Dry-aging fish is about patience and control,” said Phillip Frankland Lee, co-owner and executive chef of Scratch Restaurants Group, which owns Sushi by Scratch in Denver. “When you dry age, you are effectively removing moisture. When you remove moisture, you concentrate both flavor and oil and fat. So you’ll end up with something that’s both fattier and more flavorful. Typically, you’ll also end up with a firmer product.”
Across Denver, chefs are embracing dry-aged seafood in places like sushi joints where it feels traditional, to Michelin-starred Mexican restaurants where it feels delightfully unexpected.
What is Dry-Aging
The dry-aging process is distinctly different from curing or smoking. Nothing is added. That means no salt, no smoke, and no external flavoring, it’s just time and science. Natural enzymes tenderize the fish and create a flavor with greater umami notes and smooth, rich flavor. Just as it is with meat, dry aging requires a special refrigeration cabinet to control moisture, humidity, and temperature, and uses UV lights to kill any bacteria.
“The duration of dry aging varies significantly based on the cut size and desired outcome. The bigger the cut, the longer you’ll age it for,” Lee continued. “It all depends on the specifics of what the fish is and what you’re going for.”
At Kumoya, chef Corey Baker keeps his dry-aging cabinet set to 1°C (just above freezing) and 85% humidity, on average.
“You want it as cold as possible, right around freezing, and the humidity high so it sucks out moisture while locking in flavor,” Baker explained. “That’s what makes the fish creamier and smoother in texture.”
The preparation before aging is just as important as the cabinet.
“We scale it, gut it, and remove all the mucus and blood, [which] are what cause bacteria growth,” added Baker. “Depending on the fish, we either do sushi hiki, which is skinning the fish with a knife, basically like scaling it and keeping the skin on at the same time, which is a pretty hard Japanese technique. [Or], like with our bluefin, we basically just put big loins into our cabinet.”
Before going into the case, each fish gets washed in a salt ice bath that mimics ocean water. This technique helps to chill the fish down super fast. Next the team dries it off completely before hanging or setting it inside the case.
Choosing the Right Fish
“When it comes to selecting fish for dry aging, there isn’t a one-size-fits-all answer,” said Lee. “There’s an argument for lean fish, for fatty fish, for lean cuts, for fat cuts, for fatty cuts. It all depends on what you’re trying to accomplish in the dish and what you’re aiming for in terms of flavor profile and mouthfeel.”
Currently, at Sushi by Scratch, customers will find toro, akami (a type of lean tuna), whole salmon, and whole yellowtail in the dry ager, along special rotating options.
At Kumoya, Baker gravitates specifically toward species with fattier flesh and higher oil content. The list includes tuna, salmon, ocean trout, yellowtail, and dense white fish like Australian coral trout, sea bream, and ruby snapper. He has tried around 30 different types of fish, but now only uses between five or six of them. The shelf life, he added, is only a couple days due to the size and oil content of each fish.
“I want guests to experience what dry aging does to the fish and compare it themselves,” he added. “Often, we’ll serve a 30-day, dry-aged toro right alongside a fresh bluefin toro that just came in that day. Serving them side by side lets people taste the difference for themselves.”
A Mexican Twist on Dry Aging Fish
At Mezcaleria Alma, which just earned its first Michelin star, Johnny Curiel experiments with dry aging in a unique way that puts a twist on Mexican cuisine’s typical fresh seafood approach.
“Right now, we’re lucky to get beautiful seafood from Mexico, which we fly into DIA,” Curiel shared. “In Mexico, seafood culture is all about freshness, you catch it today, you eat it today. But for me, I wanted to push past that and learn more about dry aging, experiment with how far we could take the quality. The fish we serve at Mezcaleria Alma now is superior to what we could offer if we were only focused on day-of freshness.”
One example is Mezcaleria Alma’s ceviche, which uses Guachinango, a type of red snapper from Baja. Rather than using the traditional technique of letting the fish sit in a citrus lime bath for several hours, which breaks down the proteins and “cooks” the fish, Curiel dry ages the snapper for three days. For the high citrus flavor typically found in ceviche, he serves the fish with a salsa de molcajete (a tomato salsa in a citrus broth with habanero) on the side and instructs the guests to mix it in at the table.
“We don’t want the lime or the orange to do the speaking, we want the red snapper to do it since we’re putting in that much time into the fish,” he explained.
In fact, all the fish found on Mezcaleria Alma’s menu is dry aged. The reason comes partially because of the restaurant’s small footprint, as well as Curiel’s desire to push the boundaries of traditional Mexican cuisine.
“We have a small kitchen, we’re landlocked, we don’t have a prep area, so it’s like, how do you extend your shelf life on fish,” Curiel said. “When we opened Mezcaleria, I really wanted it to be like Mexico City, which is doing a great job when it comes to seafood restaurants.”
The chef not only wanted to do high-quality seafood, something, he added, that anybody can get if they want. Instead, he wanted to explore how he could go above and beyond and leaned into learning more about dry aging and fish.
Other standout dry-aged seafood dishes at Mezcaleria Alma include the recently added Crudo de Atun, a dish made with bluefin tuna made with tomato fresno broth, gooseberries, serrano oil, and avocado, finished with smoked salt; Aguachile De Erizo with Santa Barbara uni and Hokkaido scallop; and the eatery’s signature Tostada de Toro.
Old Technique, New Trend
While Mezcaleria Alma is currently the only Mexican joint serving up dry-aged fish in Denver, the trend is growing. Chef Jose Avila is planning to launch Ferozzzz next spring, a new concept which will be housed inside of his new Mexican food hall next door to La Diabla Pozole y Mezcal.
“I’ve been playing around with past and present dry-aging techniques and at Ferozzzz, we’ll be using controlled methods inspired by Japanese jukusei,” said Avila, adding he won’t just use fish, but also mushrooms, goose breasts and necks, and even rabbits. “We use a controlled refrigeration system that balances temperature, humidity, and airflow so the fish can dry-age safely while building flavor and umami.”
The rise in dry aged seafood may feel cutting-edge, but the technique is far from new. Other places around Denver dry age fish as well including Edge Restaurant & Bar in the Four Seasons Denver and Jack’s On Pearl. Lee has been doing it since 2010, long before Instagram made the technique visually viral. Baker pointed to pioneers like The Joint in Los Angeles, which helped push the practice into mainstream sushi culture. And for Curiel, using techniques like dry aging is as much about spreading awareness of the possibilities of Mexican food as it is about flavor.
“I always say, it’s not just about the fish, it’s about Mexican food,” Curiel shared. “Whenever I’m talking to a guest and I use a word or say something and they don’t understand, and they pull out their phone to Google something, I feel like I’ve done my job by contributing to the knowledge. [Overall], I’m happy that dry aging is being spoken about in a Mexican restaurant.”
Other places around Denver dry age fish as well including Edge Restaurant & Bar in the Four Seasons Denver and Jack’s On Pearl. As the trend grows, we can’t wait to see what other chefs start implementing it.
