You’re making a lovely piece of salmon and just as your mouth starts watering, white gunk comes oozing across the surface of the fish. What is that stuff and how can you keep it from developing?
The white material is called albumin, which is a protein that is found naturally in salmon. The moisture-rich protein starts out as a liquid. The muscle fibers in the salmon contract as they are heated and that pushes albumin to the surface. There, it turns white and thickens.
When albumin shows up on the flesh of your salmon, it typically means that the fish has lost some moisture. Some of the protein will seep out whether you overcook it, undercook it, or perfectly cook your fish. But salmon that is cooked too long usually has the most albumin visible.
“When heated quickly from cooking the fish, all proteins coagulate and become more formed,” Caroline Thomason, RD CDCES, a registered dietitian in the Northern Virginia area, tells Spruce Eats. “However, when you cook fish very quickly or overcook it, you are more likely to see the ‘white stuff’ pop up.”
Is It Safe to Eat?
You certainly can eat albumin. It doesn’t have an impact on your dinner’s taste, but you might not like the look of that crusty goo. “Albumin is completely safe and should not have any taste,” Thomason says. “You may notice that the fish overall is tough from overcooking it, so that could be one sign to look for to prevent any unwanted taste or texture changes.”
How Do You Avoid It?
Don’t overcook salmon. Fish should be cooked to an internal temperature of 145 degrees, according to the Food and Drug Administration (FDA).
Using a meat thermometer is the best way to prevent overcooking, says Thomason. But when you prick the salmon, some juices will seep out. To prevent coagulation, quickly blot the hole with a paper towel before continuing to cook your fish.
You can also try marinating the salmon in a brine solution before cooking, which helps it stay moist. One recipe suggests about 1/4 cup salt dissolved in four cups of water. You can keep it simple, or also add extra ingredients like onion and garlic.
“Brining usually adds salt/sodium, which is absorbed by the fish and holds the liquid in the interior of the fish, instead of the liquid (and albumin) seeping out,” registered dietitian Isabel Maples, MEd, RDN, a national spokesperson for the Academy of Nutrition and Dietetics, tells Spruce Eats..
More Cooking Tips
Home cooks often overcook fish, says Maples. She suggests these tips when cooking salmon:
- Use medium temperatures, not high temperatures, especially for thick fish like salmon.
- Take salmon out of the refrigerator 15 minutes early, so it can cook more evenly.
- Pat gently with a paper towel before cooking. That lets it crisp up instead of steaming, which can release more liquid.
- Cut large salmon pieces into smaller, same-sized portions to allow for even cooking. Salmon usually takes 15-20 minutes to cook.
“Fish is done when it flakes on testing ( a fork inserted at an angle into the center and then twisted gently),” says Maples. “Fish will lose its translucent, raw look.”
And if you still end up with white gunk? Just scrape it off and enjoy your dinner!