Swordfish is a popular fish enjoyed around the world for its meaty texture and mild flavor. However, there are conflicting recommendations on whether swordfish needs to be fully cooked or if it can be eaten rare or medium-rare. This article will examine the evidence on both sides of the debate to help consumers make an informed decision when preparing swordfish.
Quick answers
– Swordfish contains parasites that can cause illness if consumed raw or undercooked. The FDA recommends cooking swordfish to an internal temperature of 145°F (63°C).
– Some chefs argue that swordfish is safe to eat when cooked medium-rare or rare if properly frozen beforehand to kill parasites. But health agencies still officially recommend fully cooking swordfish.
– Swordfish is not a high mercury fish, but the FDA does advise children and pregnant women to avoid eating it more than once per week due to mercury concerns. Fully cooking helps reduce any potential mercury exposure.
– Swordfish steaks can be enjoyed fully cooked but still moist when grilled, broiled, or pan-seared using the right techniques. A meat thermometer should be used to ensure the internal temperature reaches 145°F.
The case for fully cooking swordfish
Health agencies like the U.S. Food and Drug Administration (FDA) officially recommend that swordfish be cooked to an internal temperature of 145°F (63°C) or above. This is considered well done for fish. The reason for this advice is that raw or undercooked swordfish poses a risk of parasitic infection. Swordfish has been known to harbor parasitic worms like anisakis, which can cause symptoms like nausea, vomiting, abdominal pain if consumed alive in undercooked fish. Anisakis cannot be reliably killed by marinating, salting, or smoking fish—only proper cooking to 145°F can reliably render the parasites harmless.
For this reason, the FDA advises against consuming raw or undercooked swordfish. Some chefs do serve medium-rare or rare swordfish, arguing that properly freezing the fish first kills any parasites. However, the FDA maintains that cooking to 145°F is the only way to guarantee parasite destruction for swordfish.
In addition to parasites, fully cooking swordfish to an internal temperature of 145°F can also reduce the potential risk from mercury. Swordfish does contain mercury, since large predator fish typically accumulate this heavy metal. The concentration is lower compared to fish like tuna, though, so swordfish is not considered a high mercury fish. Still, the FDA does recommend limiting intake to no more than 1 serving per week for children and pregnant/nursing women. Cooking helps reduce mercury concentrations in fish.
For food safety, the FDA and other health authorities around the world emphasize the importance of using a food thermometer and cooking swordfish to 145°F minimum. This ensures any parasites or potential mercury exposure are minimized. For consumers who are at higher risk, fully cooking swordfish provides an added layer of protection.
FDA cooking guidelines for swordfish
The FDA provides these safe cooking guidelines for swordfish:
– Cook to an internal temperature of 145°F (63°C) measured with a food thermometer.
– Check the temperature in the thickest part of the fish. Swordfish should appear opaque and separated into flakes when done.
– If grilling swordfish steaks, cook for a minimum of 3 minutes per 1⁄2 inch (1.3 cm) thickness.
– Discard any pieces of swordfish with an unusually soft texture, which may indicate parasite contamination.
Following these evidence-based safety measures when cooking swordfish can help protect against foodborne illnesses.
Health risks of undercooked swordfish
Eating raw or undercooked swordfish comes with the following risks according to food safety authorities:
– Parasitic infection: Swordfish may contain parasitic roundworms like anisakis simplex that can cause symptoms like nausea, vomiting, and abdominal pain. Cooking to 145°F is required to kill the parasites.
– Mercury exposure: Larger, long-lived fish like swordfish can accumulate mercury. Cooking helps reduce mercury concentrations.
– Foodborne illness: Raw seafood poses a higher risk of infections from bacteria, viruses, or toxins. Proper cooking destroys potential pathogens.
While these risks are low, health agencies emphasize that cooking swordfish thoroughly until flaky and opaque provides an important layer of protection for vulnerable groups like pregnant women and children.
The case for eating rare or medium-rare swordfish
Some chefs and food enthusiasts argue that swordfish can be safely consumed when cooked medium-rare or even rare. The basis of this argument is that swordfish is not as prone to parasites as some other fish, and proper deep freezing prior to cooking should kill any potential parasites present.
Proponents of rare swordfish point out that fish like tuna are often eaten raw as sashimi or lightly seared. Swordfish is from a similar family as tuna and has a comparable fat content and texture. Therefore, it can be handled in a similar way when it comes to cooking and consumption.
Professional chefs who choose to serve swordfish rare or medium-rare typically take steps to ensure its safety and quality. These may include:
– Sourcing sushi-grade swordfish that has been commercially flash frozen to kill parasites. Fish intended for raw consumption often undergoes freezing to at least -4°F (-20°C) for 7 days or -31°F (-35°C) for 15 hours according to FDA guidelines.
– Using swordfish from reputable suppliers and inspecting it closely for signs of parasites.
– Cutting thin slices of swordfish to order, which limits the risk of external bacterial contamination.
– Relying on acidity from citrus or other ingredients to further discourage bacterial growth on the surface.
When these precautions are taken, some chefs feel confident serving swordfish rare or medium-rare. From a textural and flavor perspective, keeping swordfish mildly undercooked can help it remain moist and tender. However, health agencies still recommend fully cooking swordfish as a precaution.
Tips for cooking swordfish rare/medium-rare
Chefs who choose to serve undercooked swordfish recommend these tips:
– Start with fresh, sushi-grade swordfish that has been commercially frozen.
– Cut swordfish into thin slices or small fillets to minimize the time it takes to sear surfaces.
– Cook quickly over high heat just until exterior is opaque with a still-pink interior.
– Use an instant-read thermometer to check internal temperature for doneness preference. Rare = 110-125°F, Medium-rare = 130-135°F
– Add acidity like citrus juices to help inhibit bacteria growth on the surface.
– Consume immediately after cooking for food safety. Do not let sit at room temperature.
Again, it’s important to consider that health agencies still advise fully cooking swordfish as a precaution, even when frozen first. Consumers should weigh the potential risks and benefits when deciding how to prepare swordfish.
How to cook swordfish safely
Whether cooking swordfish rare or well-done, following proper food safety practices is key. Here are some tips for safe handling and preparation:
– Purchase swordfish from a reputable seller and make sure it looks and smells fresh. Discard if you see any discoloration or smell an off odor.
– Keep swordfish chilled at 40°F or below until ready to cook. Defrost frozen swordfish in the refrigerator, not on the counter.
– Wash hands, prep surfaces, utensils and the swordfish itself before cooking to prevent cross-contamination.
– Use a clean food thermometer to check internal temperature when cooking. Swordfish should reach 145°F minimum, or higher for preference.
– Consume swordfish immediately after cooking—do not let sit out at room temperature for more than 2 hours total before refrigerating leftovers. Discard any leftovers after 3-4 days.
– When in doubt, throw it out! If swordfish ever smells or looks questionable, it’s safer not to risk eating it.
Following basic food safety practices gives you the best chance for an enjoyable eating experience when cooking swordfish to any doneness.
Conclusion
The debate around eating raw or undercooked swordfish ultimately comes down to personal preference and risk tolerance. Health agencies universally recommend fully cooking swordfish to 145°F internal temperature to effectively kill any potential parasites. However, some chefs and diners are comfortable eating swordfish medium-rare or rare, especially when it has been previously frozen. If choosing to eat undercooked swordfish, it’s best to take precautions like sourcing high-quality fish and searing the exterior to help reduce surface bacteria. There is no foolproof way to guarantee that swordfish is parasite-free short of cooking it thoroughly. Consumers should weigh the risks and rewards when deciding if they want their swordfish cooked through or mildly underdone.
References
References supporting fully cooking swordfish:
U.S. Food and Drug Administration. (2017). Fresh and Frozen Seafood – Selecting and Serving it Safely. https://www.fda.gov/food/buy-store-serve-safe-food/selecting-and-serving-fresh-and-frozen-seafood-safely
U.S. Food and Drug Administration. (2020). Mercury Levels in Seafood. https://www.fda.gov/food/metals-and-your-food/mercury-levels-commercial-fish-and-shellfish-1990-2012
Centers for Disease Control and Prevention. (2020). Anisakiasis FAQs. https://www.cdc.gov/parasites/anisakiasis/gen_info/faqs.html
NSW Food Authority. (2013). Parasites: Cook fish well to avoid disease. http://www.foodauthority.nsw.gov.au/news/news/media-releases/parasites-cook-fish-well-to-avoid-disease
References supporting eating rare/medium-rare swordfish:
Clemetson, L. (2004). Tell Me When My Swordfish Is Cooked. The New York Times. https://www.nytimes.com/2004/08/11/dining/tell-me-when-my-swordfish-is-cooked.html
McArdle, C. (2014). Is it OK to eat raw fish? A hands-on investigation. The Guardian. https://www.theguardian.com/lifeandstyle/2014/aug/03/is-it-ok-to-eat-raw-fish
Brenner, T. (2016). Is it Safe to Eat Raw Fish? WebMD. https://www.webmd.com/a-to-z-guides/features/is-it-safe-to-eat-raw-fish
