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Is Ceviche Really Safe? Ask Paul

And how does acid “cook” food?
By Published Aug. 31, 2022

Emily asked: “Is ceviche really safe?”

The short answer: Ceviche is only as safe as the fish you start with, so you should only make ceviche with fish that you would be fully comfortable serving raw.

With really good fish, ceviche is one of the most delicious things you can make. All you have to do is cut the raw filleted fish into small, bite-size chunks; refrigerate it for a few minutes to a few hours in an acidic marinade (usually involving lime juice) to “cook” the fish; and then serve.

It is those quotation marks that always show up around “cook” that we are here to look at more closely today. What does the acid do exactly? Is it comparable to cooking the fish with heat?

How Does Ceviche Work?

When the acidic marinade encounters the myosin proteins that make up the muscle of the fish, those proteins coagulate, bonding together and making the muscle firmer and opaque. The process is more gentle than heating, so the texture remains tender and moist, without the dryness that comes so easily to cooked fish.

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In ceviche that’s marinated for a short time, only the surfaces of the pieces of fish are transformed by the acidity, while the centers of the pieces are still translucent. A longer marination allows the acid to diffuse through the fish until it’s opaque all the way through, with a firmer texture that lacks the slightly tacky smoothness of raw fish.

Four pieces of raw fish marinated for ceviche

Is Ceviche Really Safe?

While ceviche isn’t actually cooked, the short-term exposure to acid does have an antimicrobial effect—in other words, it can kill or slow the growth of microorganisms, including potential pathogens—but it’s not nearly effective as heat is, especially when it comes to killing parasites. 

For that reason, ceviche should be treated like raw fish: Buy the best, freshest, most delicious saltwater-species (not freshwater) fish you can from a fishmonger you trust, looking or asking for a “sushi-grade” label if possible. Serve it as soon as you can, and do not serve it to pregnant or immune-compromised persons.

Ask Paul Adams, senior science research editor, about culinary ambiguities, terms of art, and useful distinctions: paul@americastestkitchen.com

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JC
JOHN C.
16 days

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too. I've done this using a rimmed sheet pan instead of a skillet and put veggies and potatoes around the chicken for a one-pan meal. Broccoli gets nicely browned and yummy!

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too.

MD
MILES D.
JOHN C.
9 days

Amazed this recipe works out as well as it does. Would not have thought that the amount of time under the broiler would have produced a very juicy and favorable chicken with a very crispy crust. Used my 12" Lodge Cast Iron skillet (which can withstand 1000 degree temps to respond to those who wondered if it would work) and it turned out great. A "make again" as my family rates things. This is a great recipe, and I will definitely make it again. My butcher gladly butterflied the chicken for me, therefore I found it to be a fast and easy prep. I used my cast iron skillet- marvellous!

CM
CHARLES M.
11 days

John, wasn't it just amazing chicken? So much better than your typical oven baked chicken and on par if not better than gas or even charcoal grilled. It gets that smokey charcoal tasted and overnight koshering definitely helps, something I do when time permits. First-time I've pierced a whole chicken minus the times I make jerk chicken on the grill. Yup, the cast iron was not an issue.