11 Red Flags The Seafood You’re About To Buy Is Going Bad

Seafood pros weigh in on ensuring there’s nothing fishy about your fish purchase.
Open Image Modal
ingwervanille via Getty Images
Clear eyes, fresh fish, can't lose.

There’s no better time to dive into eating more seafood. Tinned fish is having what we thought might be a moment but will likely turn into a chapter; a wider variety of sustainable and BAP-certified (Best Aquaculture Practices) seafood is making it easier to consume it more responsibly; general fatigue has made dinner proteins that cook in minutes especially appealing, as well as any food to help support our tired bodies with omega-3 fatty acids.

Seafood is loaded with healthy nutrients and lean protein, and then there’s the simple fact that when it’s fresh, it’s damn delicious. 

But therein lies the caveat: when it’s fresh. The delicate fruits of the sea are highly susceptible to spoilage, sensitive to improper storage, preservation and even thawing. And unless you’re catching it yourself or buying BAP-certified (which allows you to follow its trail), it’s hard to know exactly what kind of journey your seafood had before it arrived at the store.

If your seafood has anything less than the royal treatment, you could suffer through scombroid poisoning — a histamine-producing reaction — as soon as 15 minutes after it enters your digestive tract. That’s why it’s important to be aware of red or even orange flags that good fish is on the cusp of going bad.

1. Lack Of Visual Appeal

The first thing that Okan Kizilbayir, the executive chef for the AAA Five-Diamond Salt at The Ritz-Carlton, Amelia Island, advises is to “Just look at it. If you don’t like it, don’t buy it.” And this can extend to how it’s merchandised. The FDA suggests that you “only buy fish that is refrigerated or displayed on a thick bed of fresh ice, preferably in a case or under some type of cover.” This isn’t just to look nice — it helps to regulate the temperature and food safety, and is a good indication of how the seafood is treated.

And if the fish is whole, take a look at its eyes. “Are they clear, hazy or turbid?” asked Eddie Barret, executive chef at Atlanta seafood restaurant BeetleCat. Michael Nelson, executive chef of GW Fins in New Orleans, added another criteria: that the eyes shouldn’t be sunken in, either. “They should appear clear and almost alive and looking back at you.” If there’s anything that sets your Spidey-sense tingling, go elsewhere or pick another fish.

2. Odor

Sometimes, you don’t even need a visual to know to walk away. For many professionals, the sniff test is the first and most important one they conduct. 

“A good fishery should smell like the ocean,” Kizilbayir said. “There might be a very bad mussel standing in the corner of the ice and that would ruin the entire smell of the area; this happens all the time.” Even so, that’s his cue to proceed with some caution and impetus to “get your nose closer to the fish in order to choose the best one.” The less you smell, the better it is, because fresh fish doesn’t actually smell “fishy”; a quick whiff shouldn’t include sour or ammonia-like surprises. “Does it smell gassy, foul or off-putting in any way? That’s the first dead giveaway for us,” Barrett said.

“If you get close enough to smell the inside of the gills, it should only smell of the ocean. It will be a subtle, clean scent,” said Pattie Lawlertratana, chef-owner of Snap Thai Fish House in Atlanta. 

3. Squishy, Squidgy Fish

Getting up close and personal with your seafood is something you oughtn’t be shy about. Reputable purveyors like fishmonger Frank Palermo, owner of Claws Seafood Market, a chemical- and preservative-free seafood shop on Long Island, New York, will stand by their product, so go ahead and ask to give it a good poke.

“There should be resilience to the touch,” he said; “the flesh needs to bounce back a little bit,” Kizilbayir said. That’s because “some fish will break down as they sit, resulting in mushy-feeling fish,” Barrett explained. 

Additionally, you want to get your hands on the skin to ensure it’s not slimy, sticky or missing scales, Lawlertratana said. According to Nelson, the former two criteria also applies to fillets. “It’s a sure sign it has spoiled.” However, “a clear, viscous film on the outside is usually a sign that the fish was recently caught,” so be sure not to confuse that with sliminess. 

4. Brown Gills

“If the gills have started turning brown, that’s a pretty clear sign it’s been sitting. Fresh fish should have reddish-pink gills,” Barrett said. “Or bright red,” Palermo said. “Brown blood or gills are a hard no for me.” 

You can also check freshness by the bloodline. “If it has one, like snapper or redfish,” Barrett advised. “If it has some age on it or has been previously frozen, it will appear brown or gray. You don’t want to use that fish!” Nelson said. “If fresh, it should appear cherry red.”

Brown tinges are also a no-no for filleted fish. “If the fish has started discoloring, especially around the edges, it’s a sign of age,” he said.

Other colors you want to avoid are gray, said Sherri Clerk from the Global Seafood Alliance. “Particularly with a milky film,” she cautioned. This “glossy white film,” as Barrett describes it, is a clear indication that the fish has been sitting out for too long.

5. A Curled Tail

“If the tail appears dry, frayed or curled, that can be a sign that the fish could have been temperature-abused,” Nelson warned. “This could include being left on the deck of a boat too long,” in which case the damage was done long before it hit the seafood case. 

6. A Torn Belly

A whole fish with its insides left intact will always start to spoil from the inside, from the belly,” Palermo warned. “Any sign that the belly is torn would be a true indicator that the fish is aged.” 

However, even if the whole fish has been gutted, it’s still worth checking. In this case, he said, if the rib cage bones are separated, this fish should be a hard pass. That means that the fish has been out long enough for its membranes to dry out and begin decomposing.

Open Image Modal
Calvin Chan Wai Meng via Getty Images
Live clams that are open should immediately close when you tap them.

7. Sleepy Shellfish That Won’t Close With You Tap Them

The one main criteria for ensuring that your shellfish is stomach-safe is that it’s alive when you cook it, and as Kizilbayir points out, “One dead bivalve might ruin all those around them.” 

“They should be completely closed before they have been cooked,” Nelson said. “They start to open if they are out for too long,” Kizilbayir explained. “You can hit them against each other if you see any movements of closing; that’s a good trick. If they aren’t moving, they’re not good.” 

Lawlertratana says, “Fresh bivalves will be tightly shut or will close when tapped. If they remain open after tapping, they might be dead and are unsafe to eat.” 

Yet when cooking, you want the opposite reaction. “If they don’t open while cooking, throw them away and do not force them open!” Nelson said. While it won’t impact the safety of its fellow mollusks at this stage, this is a sure sign that it’s the bad egg of the batch.

8. Old Or Missing Tags

“By law, all shellfish displayed for sale must include tags that tell the customer: the location the shellfish was sourced from; day the product was harvested; day the product was shipped to the final retailer,” Palermo said. The FDA adds that it also includes the processor’s certification number. 

“Using the tag that the bivalve comes with is a surefire way to know it’s fresh. You want to ensure they are used within seven days; return anything that you receive that is outside of seven days of the current day,” Barrett added. 

9. Dry Shells

“Clams, oysters and mussels should be kept on ice and should look moist and not dried out,” Nelson said. A lesser-known fact Kizilbayir shared is that “their shells get very dry and they’ll start to stink way earlier than fish!”

Palermo looks for shells that are dark and damp, as “over time, they tend to turn much lighter in color and eventually dusty white.”  

The moisture level inside the shells matters, too. Lawlertratana said, “If there’s any liquid in the container, it should be clear, not cloudy.” Nelson adds to that some specifics on oysters: “When shucking, they should smell of the ocean and be full of natural briny liquid. If it smells off or is dry inside, do not use!” 

10. Unlively Crustaceans

“The best way to get crustaceans is when they’re still alive,” Kizilbayir said. According to the FDA, crustaceans spoil rapidly after death, which is why chefs like Nelson and Lawlertratana seek out the most active crabs and lobsters. The FDA’s lead tip is that you check for leg movement. “Do not use if they are dead!” Nelson said.

However, Palermo revealed, “Even if they’re moving, that doesn’t mean you’re guaranteed a quality product. Lobsters and crabs go through a molt typically once per year. Once they molt and the new shell is formed, it takes time for the animal to fill the shell. New shell lobsters are usually always on sale and should be advertised as ‘new shell,’ lighter in weight and meat fill. But this meat can sometimes be mushy when cooked and very unpleasant.” His advice is to go ahead and pony up for the hard shell. 

11. Suspicious Shrimp

“Shrimp should be translucent and have a slight sheen,” Lawlertratana said. “If they appear overly dry or have black spots on their shells,” — melanosis, she explained — “they’re not fresh.” 

Nelson only uses domestic wild shrimp versus imported farm-raised shrimp, and advises that you buy them frozen and thaw it in cool water right before you plan on cooking. Any sooner and you’ll risk spoilage.

“Lobster, shrimp, and crab will always develop a slimy coating if sitting for too long. They’ll also go from smelling sweet and yummy to sour and off-putting very quickly,” Barrett said. 

Last Tips

As you can see, there are plenty of safety checkpoints to ensure that the seafood you’re about to buy is good to go and safe to eat. However, your best chance of success is to abandon any shyness. Step up and be forward with your questions, even if it’s just at your local supermarkets. 

“Know where your seafood is coming from! Especially with packaged seafood sales in supermarkets,” Kizilbayir said. Seasoned pros like Palermo, who used to run a supermarket seafood sales division prior to opening up his market, will welcome the inquisitiveness and be eager to share the story of their food. Now as an independent fishmonger, this applies more than ever, which is why Lawlertrana says, “Always ask your fishmonger for advice; they can tell you what’s freshest that day. Ask about the catch of the day and its source. Look for vendors with a lot of local customers as they’re likely more reputable.”

After all, “Building great relationships with vendors” — whether you’re a career chef or a home cook — “is key to ensuring that the product you’re bringing in is the best quality and fresh,” Barrett said. With a trusted fishmonger, you won’t need to remember all of these red flags. As Palermo jokes, “We would have ‘caught’ them already!” 

Our 2024 Coverage Needs You

As Americans head to the polls in 2024, the very future of our country is at stake. At HuffPost, we believe that a free press is critical to creating well-informed voters. That's why our journalism is free for everyone, even though other newsrooms retreat behind expensive paywalls.

Our journalists will continue to cover the twists and turns during this historic presidential election. With your help, we'll bring you hard-hitting investigations, well-researched analysis and timely takes you can't find elsewhere. Reporting in this current political climate is a responsibility we do not take lightly, and we thank you for your support.

to keep our news free for all.

Support HuffPost

Before You Go

27 Kitchen Products From Amazon You'll Use So Often, They'll Practically Pay For Themselves
A trio lasagna pan(01 of27)
Open Image Modal
Promising review: "Question: What do you do if you are a vegetarian and your family eats meat and you want a lasagna but don't want to make two full pans? Answer: Get this product right now! With this pan you can make a quick meal since you don't have to cook the noodles, even with the regular lasagna noodles. I find the walls of these pans are compact and the heat from the channels cooks the pasta around it quickly, resulting in fork-tender lasagna without boiling first. The trick is to use a lot of sauce and cover it with foil. The added bonus with this pan is the fact that the leftovers can be stored easily and simply in containers ready to go for tomorrow's lunch — no cutting and messing with lasagna slices in a flat pan. Take care of your products though, as others have said, do not let this soak in water too long or it may rust." — PinkSugar (credit:www.amazon.com)
A veggie chopper(02 of27)
Open Image Modal
Check out a TikTok of the veggie chopper in action.

Promising review: "Makes life so much easier. I can't imagine chopping onions or bell peppers by hand anymore, and it does so much more. We used to have a Prepworks chopper which was a similar idea, but you had to press so hard to chop, and it broke after not too long. This one requires very little effort to cut through the food and it has a generous container." — Amazon customer
(credit:www.amazon.com)
A rotary cheese grater(03 of27)
Open Image Modal
Promising review: "I love it. My family loves it. We used to use a handheld flat cheese grater. It took forever to grind enough cheese out of that thing. This little jewel cranks out grated cheese. We tried all sorts of hard cheeses just to see the thing work, then froze some soft cheeses to see how they worked. Now we mix our cheeses just because it is so easy to do. Asiago/Parmesan rockfish? Simple. Pretty neat. It works. It's cheap. Easy to clean. Handy as hell. Buy one." — Aranhas
(credit:Amazon)
A pair of left-handed scissors(04 of27)
Open Image Modal
Promising review: "So my three youngest are left-handed even though no one else in the family is. Now that they are teens their school-sized left-handed scissors don't fit their hands. I ordered these because we have always used Fiskars school stuff, especially scissors. They are just what I was hoping they would be. And my teens are so excited to not have to use the regular kitchen scissors anymore. Sounds funny, but when you are left-handed those things make a big difference. I am going to order a few more pairs. Great scissors!" — oliveoil

(credit:amazon.com)
A handheld milk frother(05 of27)
Open Image Modal
Promising review: "This makes the creamiest froth ever! I am completely blown away by the results of this device. I had no idea that I could make froth at home like this. This changes my whole cappuccino experience!!!" —Wells

(credit:amazon.com)
A clip-on pasta strainer(06 of27)
Open Image Modal
Promising review: "Pouring a scalding hot pot of pasta into a colander brings back memories of said colander tipping over and pasta spilling all over the sink or the bottom portion of pasta sitting in a shallow pool of water you just poured into the sink. Not to mention the splash back when the water hits the rim or side of the colander just perfectly. This product relieved me of having to worry about those catastrophic events. Just snap onto your pot while still having two hands to control the pour." — John C

(credit:amazon.com)
A salad spinner(07 of27)
Open Image Modal
You can use it for fruit, too!

Promising review: "I cut one whole head of lettuce and filled it up to wash, and it fits with the lid on. It doesn't squish the lettuce and all the parts feel well-made. I like that everything is clear and see-through so you can see the color of the water. All the pieces disassemble for washing and rinsing, and they don't have too little spaces that trap lettuce." — amy_inca
(credit:amazon.com)
A handheld surface 3-in-1 steam mop(08 of27)
Open Image Modal
Promising review: "I absolutely love this little powerhouse! I use it regularly in my kitchen, particularly around and inside of my oven, and all around my bathroom! The brush adapters are perfect for cleaning tile/grout and the hard-to-reach small areas around the outside and inside of my stovetop/oven (I have a dedicated brush for each) and it cuts right through grease. Because the reservoir only holds a certain amount of water you will need to refill it and let it warm back up but it gives your hand a rest in between. Definitely recommend!" — Melissa

(credit:amazon.com)
A cast-iron Dutch oven(09 of27)
Open Image Modal
Promising review: "Wow I don't know how I lived without an enamel Dutch oven for so long! We use this for so many recipes, whether or not this is technically the best pot to use for them. I love that the enamel is safer and more durable than nonstick but doesn't sacrifice that function. We only hand wash it because we don't want to ruin the finish, but that has been very easy so far. It is also great for baking. Overall, could not be happier with this product." — RMS
(credit:amazon.com)
An electric can opener(10 of27)
Open Image Modal
Promising review: "This is an amazing tool! It's about the same size as a manual can opener, but this is automatic. All you have to do is place it on the can and press the button and it turns on its own. Just press the button again once it reaches the starting point and it disengages and turns off. This doesn't leave sharp lid edges like regular openers. What a lifesaver!" — Rachel Young
(credit:amazon.com)
A chopper tool(11 of27)
Open Image Modal
The tool is safe to use with nonstick cookware and you can throw it in the dishwasher for easy cleanup.

Promising review: "The chopper breaks up ground beef, turkey, etc. much more efficiently than can be done with a spatula or turner. I don't normally purchase incredibly specialized utensils if I can get by without them, however, I think this chopper is worth the money because it saves time and makes cooking easier. The nylon material is heat-resistant and seems durable, but the packaging still directs not to leave on a hot surface when not in use." — Karen
(credit:Amazon)
An instant-read digital thermometer(12 of27)
Open Image Modal
Promising review: "As a working chef for over 30 years, I've gone through dozens of thermometers, and this one stands out. I actually purchased this by accident while buying several thermometers to try with the intent of buying a dozen for my crew. I was looking for thermometers that can be field-calibrated and as far as I can tell, this one can't. But I intend to buy more of these because they are accurate, easy to read, and just more pleasant to use. They are tough, and I love the ring on the end; I keep this one hanging on a hook near our ranges so I don't have to hunt it down. It does not ride easily in my chef's coat, but that is due to the longer probe. Which I LOVE. In two weeks I have used this one thermometer over 130 times, all with pleasure." — Cetaceous Dave (credit:Amazon)
A vented microwave food cover(13 of27)
Open Image Modal
Promising review: "This is my third one. One was melted on the stove burner recently by someone I seem to have married who doesn't know fire is hot yet. The other lasted through five years of heavy use. It did get pitted along the inside here and there; I don't know from what, but I suspect the aforementioned person. This folds absolutely flat and can be used as is or partially opened for a thinner cover to put over a bowl, say. Not difficult to clean since things don't really stick to it but if you have a mess it just takes a small second to make sure the folds and holes are all clean. This is also great for making microwave popcorn, putting corn in a bowl and using this to allow air flow. It will raise up as popcorn pops and fills bowl. Another neat gift to give someone since it's a handy gadget that saves space and something you'd use a lot." — Ms. Windermere
(credit:www.amazon.com)
An all-in-one measuring cup(14 of27)
Open Image Modal
It's dishwasher- and microwave-safe. Measurements include: 1 cup, ½ cup, ⅓ cup, ¼ cup, 2 tbsp, 1 tbsp, ½ tbp, 1 tsp, ½ tsp, ¼ tsp, 120 ml, 80 ml, 60 ml, 30 ml, 15 ml, 7.5 ml, 5 ml, 2.5 ml and 1.25 ml.

Promising review: "First of all, I gotta say I don’t cook much and if there’s something I hate after cooking is having to wash all the bunch of utensils I have to use once I use them. This cube has been amazing, I don’t have to wash a million utensils over and over, it’s very easy to use, easy to clean and it’s very handy to use for when I’m meal prepping for the week. I bought this out of curiosity and ended up enjoying it a lot. If a regular guy like me is enjoying it, I’m sure it would be a great tool for people who cook or bake on a regular basis." — Daniel Matajira
(credit:Amazon)
Or a set of space-saving measuring spoons(15 of27)
Open Image Modal
Promising review: "I got so tired of measuring spoons either getting lost in my drawer or having to deal with ones on rings. These are fantastic. The magnet holds them together well, and I love that each ‘spoon’ is actually two (each end is a different shape, too)." — Alicia S.
(credit:Amazon)
An egg bite maker(16 of27)
Open Image Modal
Promising review: "I bought this in hopes to make egg bites similar to Starbucks and I have not been disappointed. I chose this one after reading reviews on the smaller four-bite size. I have used it multiple times and have had excellent results each time. I followed the recipe in the booklet and used a tip from another reviewer that suggested to triple the cottage cheese amount. It’s very easy to use and clean." — April124
(credit:www.amazon.com)
Or a rapid egg cooker(17 of27)
Open Image Modal
Promising review: "I saw someone on TikTok with this and gasped! Ordered it right away. I had no idea these things existed. Super easy and convenient and the hard-boiled eggs came out perfectly. I’m testing a batch now without punching a hole in the eggs to see how they come out. Because why not make an easy process even easier?!?! LOL." — Gina
(credit:www.amazon.com)
An anti-soggy cereal bowl(18 of27)
Open Image Modal
Promising review: "This product is something I didn’t know I needed. It’s like the creator crawled into my soul and found the deepest desire of my heart and then invented it. If you think I’m being dramatic, you should try soggy cereal and then eat cereal from THIS bowl. I’ll take 30 more, please, and hand them out as gifts." — Sarah F.
(credit:www.amazon.com)
A Yonanas fruit soft-serve maker(19 of27)
Open Image Modal
Promising review: "I saw one of these in action at a friend's house like five years ago and thought it was just a made up memory, because making ice cream out of solely frozen fruit seems wild. But when I saw a TikTok about it I immediately went to Amazon and bought it. Literally this was the BEST decision of my life. I cannot believe still how amazing this thing is! It makes the creamiest, best tasting fruit ice cream ever. It’s easy to take apart and clean, and super easy to use." — DMCKAY
(credit:www.amazon.com)
A fantastic combo air fryer and oven(20 of27)
Open Image Modal
Promising review: "I never had an air fryer before, but now that I have one (in the toaster oven), don't know how I lived without it! This little oven does it all! Easier to clean with the slide-out tray and the air fryer, oven, and broiler (that's all I've used so far!) all work great! Can't wait to try and make my own beef jerky! Best money I've ever spent on a small appliance!" — Ally

(credit:amazon.com)
And some silicone air fryer liners(21 of27)
Open Image Modal
Promising review: "I have had an air fryer for years and am just now finding out about these things?! So easy to pop in the dishwasher rather than having to clean the air fryer basket. I still wipe down the basket from juices while cooking, but overall these are now a must in my house." — Madeline Curry
Price:$11.99
(credit:amazon.com)
A teeny-tiny mini waffle maker(22 of27)
Open Image Modal
Promising review: "At first, I laughed thought it was too small to really do anything. I was so wrong — it's an amazing little waffle maker!! Can cook almost anything on it! I have cooked eggs, waffles, and French toast." — S PETERSON
(credit:www.amazon.com)
A heat-safe, durable pizza stone(23 of27)
Open Image Modal
Promising review: "Absolutely awesome way to cook either a homemade pizza or a frozen store bought pizza! If you’re sick of your pizzas not cooking fully and/or correctly, I highly recommend this product!! It’s oversized surface makes cooking any size pizza extremely fast and easy!" — Calvin W Bulford
(credit:www.amazon.com)
A breakfast sandwich maker(24 of27)
Open Image Modal
Promising review: "Single best appliance I own. My boyfriend sent me this sort of as a joke; we both thought it was both ridiculous and brilliant to have a McMuffin maker in your house. And then I tried cooking with it for the first time. Holy crap, it's AMAZING. I ended up using frozen waffles for the bread; you have to trim them just a tad, but they are the perfect amount of crispy. I love experimenting with this, and have built some truly amazing sandwiches. Waffles, eggs, avocado, Swiss, and ham. Waffles, egg, corn salsa, jack cheese. If you can fit it into the rounds, you can make a sandwich with it. The panel under the egg slides out easily and cleanly when the egg is cooked (I find four minutes is perfect for cooked eggs with runny yolks), and the whole middle section can simply be tossed in the dishwasher." — Elizabeth Joy Weaver
(credit:www.amazon.com)
A KitchenAid mini stand mixer(25 of27)
Open Image Modal
This 3.5-quart mini mixer includes a wire whisk, flat beater, and dough hook. It is dishwasher-safe and sports a powerful 10-speed slide control.

Promising review: "I’m in love! I’ve been waiting to buy a mixer for so long and I finally pulled the trigger. I was hesitant to purchase the mini thinking it was too small — boy was I wrong! This powerful little machine is already the bell of the ball in my kitchen. Don’t let the word 'mini' scare you off, this has no problem making double batches of bread. If you’ve been thinking about buying one, don’t hesitate; you won’t regret adding this beauty to your kitchen arsenal." — Dani
(credit:www.amazon.com)
A set of two baking mats(26 of27)
Open Image Modal
Promising review: "I have no complaints. They are easy to clean and keep stuff from sticking. I have used them several times without any issues. I haven't ever used the name-brand ones, but these are pretty darn good from what I have seen." — braingamer47
(credit:amazon.com)
And finally, a stunning set of nonstick cookware(27 of27)
Open Image Modal
This nine-piece set comes with a 8.7-inch/10-inch frying pan, 2.4-quart saucepan with a lid, a 4.3-quart casserole pot with a lid, and a 4.5-quart saute pan with a lid and turner.

Promising review: "Ok, I don't post many reviews. This cookware set is worth a review. By far the best cooking set I have ever owned for this price. I also purchased the Carote 6-Qt Nonstick Deep Frying Pan with Lid [and] 12.5-Inch Skillet Saute Pan (monster). The construction is high quality. The non-stick is really non-stick. So far, I have cooked 12 or so meals with the set, and it has been great. I have also deep-fried with the set with no issues. Warning the handles will get warm most of the time and hot on occasion (deep frying). Very much worth the purchase." — Warren
(credit:amazon.com)

HuffPost Shopping’s Best Finds

MORE IN LIFE