The Case for Conservas: A Guide to Iberian Canned Fish and Seafood

overhead shot of an array of tinned fish, or conservas, on a wooden table with bread and olives.

[Photographs: Vicky Wasik]

The average American grocery store tends to be lacking in the canned seafood department. Besides shelves and shelves of tuna, one might find the odd can of clams, some salmon, some mackerel, and little else. But citizens of the Iberian peninsula—the region including Spain and Portugal—are practically swimming in canned seafood. Entire shops in Portugal and grocery aisles in Spain are dedicated to the stuff. Though fish and shellfish are eaten fresh throughout the region, canning is an often preferred method for preparing and conserving the best of their plenteous waters. In fact, the resulting range of products, called “conservas,” are considered a delicacy.

The Iberians preserve seafood by first lightly steaming or frying the product and then canning it in boiling water baths, like any other canned food. But when it comes to the liquido de cobertura (the liquid added to protect the seafood from drying out), their approach is focused on highlighting flavor and texture. Squid are often preserved in their own ink or stuffed with rice and covered in different sauces. Pricey bivalves go untampered with, and are canned in a soft natural brine to mimic the sea, while the more economical mussel usually gets the escabeche treatment—a vinegary brine of garlic, paprika, and bay leaf that was used for preservation long before canning was invented. Blue fish like tuna and mackerel have a dense texture and strong flavor that holds up to oil, and potent sardines are seasoned with every permutation of oil, spice, and tomato sauce the Iberians can imagine.

But why choose canned over fresh seafood? “The best conserva makers are canning fish caught literally the day before,” says Abel Álvarez, the chef and owner of the restaurant Güeyu Mar, and an adjacent small specialty cannery next door, in Spain’s northern coastal region of Asturias. “Why wouldn’t you maintain the freshness of that fish as long as possible?” This idea rings true with most conserva makers and consumers: canning is a way to capture the catch at its peak—a tinned time capsule of unparalleled flavor and nutrients.

The question of conservas’ sustainability isn’t black and white, but there are definitely environmental benefits to eating seafood from a can. Responsible fishing practices vary depending on the cannery, though according to Sean Barrett, co-founder of Dock to Dish, it’s easier to trace canned seafood back to its source than it is fresh seafood because of lot numbers, dates, and locations noted in labeling. He, along with Álvarez and Rafael Viguer, owner of Central de Latas in Valencia and producer of Samare Conservas, notes that canning is a more energy-efficient alternative to storing massive seasonal catches in commercial freezers. Even when considering the environmental effects of transportation, Barrett says the carbon footprint of cans is lighter. Shipping cans of seafood on slow boats across the ocean from the Iberian peninsula is preferred to sending them on a plane (the method used for sending most fresh fish around the world) or on a truck. “When considering that 90% of the seafood consumed in the US is imported, seeking out seafood from canneries using wild and well-regulated fisheries is an alternative worth seeking out,” says Barrett.

close up of mussels in escabeche on a piece of baguette with some olives on a plate

Today in the Iberian peninsula the appeal of conservas holds stronger than ever. “Spaniards care more about quality seafood than almost any other culture,” says Matt Goulding, author of author of Grape, Olive, Pig: Deep Travels Through Spain’s Food Culture. “They know some of the best stuff goes in cans.”

A popular grocery or specialty shop item, as noted above, conservas also appear on restaurant menus: In fact, some bars in Spain and Portugal serve nothing but gourmet preserved seafood. The conserva naturally weaves itself into the everyday cuisine of the region, maintaining its place as an essential pantry item for home and professional cooks. When Covid-19 hit, the Portuguese Directorate of General Health put out a 37-page gourmet guide entitled “Canned Recipes: Healthy Eating in Times of Isolation Using Canned Fish and Legumes.” The reverence, and relevance, is real.

Below is a list of cans to get you started. Serving them is simple: let the conserva shine with a few other ingredients, or eat them straight from the can with crusty bread.

Sardines (Sardinas/Sardinhas)

Packaging of Nuri spiced sardines in olive oil on yellow background

Sardines are the symbol of Portuguese cuisine, though they’re popular in both countries. You’ll find cans of small tails, some containing the full loin with skin and bones, or others completely skinned and deboned. You may be inclined to go the cleaner route, but the rich skin and subtle crunch of the spines are part of what make canned sardines so unique.

When choosing sardines in particular, look for small canneries with responsible harvesting practices, as the local Iberian stock has recently fallen because of unsustainable overfishing practices, according to seafood sustainability advocate Kate Findlay-Shirras of Best Fish Forward. There are a few stickers you can look for like MSC (Marine Stewardship Council) or ENEEK (the Basque Country's eco certification). (It's worth it to look for these stickers on other types of conservas as well.) Otherwise do your research on each cannery’s purchasing practices via their website, physical address, distribution location, and even the barcode on the label. Transparency is key: The more information the cannery provides on their practices the better.

close up of sardines in a can

The folks at Güeyu Mar are a great example and also take a more chef-driven approach. They grill their sardines before preserving them in Arbequina extra-virgin olive oil, and the flavor and texture of the tails is extraordinary. Güeyu Mar products will be available in the U.S. in late 2020.

For a classic Portuguese conserva, Lisbon culinary tour guide Melissa Haun recommends Nuri’s line of sardines, which are processed by hand. Her basic formula for enjoying these sardines: gently toss the conserva in a bowl with a legume of some kind, fresh tomatoes or peppers, and olives. Top with an acid, parsley, a hard-boiled egg, and most importantly, the remaining sacred sardine oil.

Mackerel (Caballa/Cavala)

packaging of Jose Gourmet Mackerel fillets on yellow background

There are two main types of mackerel conservas. Sometimes referred to as Atlantic mackerel or chub mackerel, these skinned and deboned filets are a great substitute for the can of overfished tuna, as they’re compact and hold up to mixing. Small mackerel (caballita/cavalinha) are also an excellent alternative to the at-risk sardines. Canneries leave these guys intact, preserving them with their spotted skin and bones.

close up of mackerel

Tejero mackerel is an economical household conserva found in many pantries in southern Spain, but it’s not readily available in the US; for a more accessible option, try Albo's mackerel in extra virgin olive oil. For small mackerel, check out Jose Gourmet’s delicate Portuguese cavalinhas in olive oil.

Use Atlantic mackerel as you would tuna or in Haun’s sardine formula. Try small mackerel on melon, with oranges and sherry vinegar, or as a garnish on ajo blanco. Again, hold on to that oil for salad dressings and garnishes by pouring it into a small container and refrigerating it until needed.

Anchovies (Anchoas)

packaging of ortiz anchovies on a yellow background

Italians opened the first anchovy canneries in Spain in 1900, preserving the fish in butter to enjoy their favorite snack straight from the can. Eventually they switched to oils, and only a few still use butter. For the best oil-packed anchovies, look to Cantabria (specifically Santoña), a region known for harvesting some of the best anchovies in the world.

Quality Spanish anchovy conservas (like Ortiz), are a far reach from the salt bombs you scatter on pizza or blitz into Caesar dressing. They’re carefully selected, hand-skinned, deboned, and canned with less salt than the common anchovy to let the natural fish flavors shine. Because they have less salt to preserve them, they’re kept in the refrigerator. Throughout Spain anchovies are elegantly strewn onto thin slices of bread or dabbed with a bit of marmalade to contrast the salinity. A tapas spot in the southern city of Seville serves anchovies in a tiny pressed sandwich with sweetened condensed milk. Also try anchovies draped over soft-boiled eggs or roasted broccoli. You just don’t want to cook with these—it's better to savor their delicate texture and flavor rather than dissolve them into a sauce.

Mussels in Escabeche (Mejillones)

Packaging of Ria de Arosa Mussels in Escabeche tin

Galicia produces the best mussels in the peninsula and the canned version’s texture is vastly different from the fresh; they're soft and velvety rather than rubbery. They’re commonly preserved in escabeche and come in two sizes, the bigger the better. These large guys mature longer on the rocks before they’re harvested, becoming plump and firm enough to hold up really well to preservation without disintegrating. Additionally, look for ones that say “fritos” (fried before canning), as frying them adds to their pleasantly meaty and juicy texture.

close up of mussels in escabeche

Ramón Peña and Ria Arosa by Ortiz are excellent brands available stateside. Toss them into pasta with garlic, lemon, and fresh mint, or do what Sevillano Luis Blanco does with a can of giant Iglesias mussels at his restaurant, Salsamento, and perch them on a pile of potato chips for a swank sea nacho. Save the remaining oil to make into mayo or drizzle over roasted vegetables.

Cockles & Clams (Berberechos & Almejas)

packaging of Matiz wild cockles

Cockles and clams are actually some of the most approachable conservas. Steamed and preserved in a simple brine, each is a tender morsel with none of the chewiness that can be off-putting in over-cooked fresh molluscs.

Matiz and Espinaler are great accessible options in the U.S., but check out the trusted brand Cuca the next time you’re in Spain.

close up of cockles in their tin

Eat clams in raw salads with lots of good olive oil or toss them into a light pasta at the last minute. Cockles are best chilled for 15 minutes with a few splashes of white wine vinegar or served ceviche-esque with red onion and cilantro, mixing the brine with the lime.

Squids (Calamares)

Packaging of Jose Gourmet spiced calamari in ragout on yellow background

Canned squid constitute a ready-made meal if you warm them up alongside a starch. The folks at Güeyu Mar serve their Calamares de Otro Planeta (calamaris from another planet) with a creamy risotto cooked in fish broth and a touch of their sharp local cheese. The grilled squid in its savory ink and sofrito gravy alongside the sweet fat of the cream is a pairing nothing short of otherworldly. Jose Gourmet similarly recommends a cream-based risotto with mint and basil for their Spiced Calamari (specifically whole baby squid) in Ragout Sauce. You can also try them with potatoes or beans.