Not many people are aware, but imported, frozen Tilapia is often treated with carbon monoxide (CO). This method is sneaky because it holds off the oxidation of the meat, which turns fish brown as it goes bad, so the fish looks fresher for longer.
The amount of the gas used to treat the fish is minimal (0. 4%) and there is no direct health risk in eating fish treated with CO. But who wants to eat fish that has been treated with any chemicals? Also, CO-treated fish makes it hard to tell how fresh the fish really is. Fish that has been treated with CO will usually look bright red (as shown above). Some people think that this means the fish is fresher, but this isn’t always the case. People who use carbon monoxide lie to customers. You can find it most often in frozen Tilapia from China, Vietnam, and Thailand. The good news is that CO is not used on Tilapia from Honduras, Mexico, or Indonesia, as shown below.
What should you look for to be sure you’re getting the freshest fish that hasn’t been CO-treated? One good tip is to look at the inside of the fish. As you can see by putting the two photos next to each other, a thawed CO-treated fillet will have a brighter and more colorful bloodline than a fresh fillet. This means that it has been treated to look fresh.
Another tip? Be mindful of where your fish is being imported from. As was already said, a lot of the Tilapia that comes into the US comes from China, where CO can be used to preserve fish as long as it isn’t eaten in China.
Choose Kirkland Frozen Tilapia Loins from Costco or fresh Tilapia from Mexico and Honduras instead of CO-treated Tilapia if you want to avoid eating it. These fillets are also 100% fish—nothing else added. They don’t have any antibiotics, chemicals, hormones, or mercury in them, so they are safe, healthy, and cheap for you and your family.
When you look at fish at the store, make sure you really look at what you’re buying next time. A few tips for identifying the freshest fish will go a long way!.
Tilapia is a popular fish known for its mild flavor firm texture, and versatility. If you regularly cook tilapia at home, you may have noticed some fillets turning an unappetizing green color. But what causes this green tinge and is it safe to eat?
In this comprehensive guide we’ll explain the common reasons for green tilapia and provide tips for selecting storing, and cooking tilapia to avoid green discoloration. Read on to become a tilapia texture expert!
What Causes Tilapia to Turn Green?
There are four main culprits that can cause your tilapia fillets to take on a greenish cast:
- Bacteria growth
- Absorption of green pond algae
- Release of gallbladder fluid
- Carbon monoxide treatment
Understanding what causes the color change is key to avoiding it.
Bacteria Growth
Like any meat, tilapia is susceptible to bacteria growth if not stored and handled properly. Bacteria multiplying on the fish’s surface can lead to a greenish, spoiled appearance. Only purchase tilapia that looks freshly caught.
Absorption of Algae
Farm-raised tilapia are often kept in ponds containing phytoplankton and algae. Absorbing this green plant matter can tint the fish’s flesh. Opt for wild-caught varieties when possible.
Gallbladder Fluid
When cleaning tilapia, greenish fluid from the gallbladder can leak onto the flesh, creating green spots. Thoroughly rinse all traces of this fluid off your fillets before cooking.
Carbon Monoxide Treatment
Some imported frozen tilapia is treated with carbon monoxide to keep it looking red and “fresh.” This can impart a greenish-grey cast. Avoid treated frozen tilapia.
Is Green Tilapia Safe to Eat?
The safety of green tilapia depends on the cause of the color change:
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Green from bacteria is unsafe – discard immediately.
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Green from algae absorption or gallbladder fluid is safe if thoroughly cooked.
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Green from carbon monoxide treatment is safe but quality is inferior.
As long as you rinse the fish well and cook to proper temperatures, algae and gallbladder-related green color poses no risks. But for peak quality, start with the freshest tilapia possible.
How to Select Fresh, Non-Green Tilapia
Follow these tips for choosing fresh tilapia fillets free of greenish hues:
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Look for firm, glossy flesh without any dull or brown spots
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Make sure the surface and scales are shiny and metallic looking
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Avoid fillets with cracked skin, loose scales, or bruising
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Opt for fillets that are translucent with visible bloodlines
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Check the sell-by date and only purchase tilapia that was freshly caught
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Ask if the tilapia was treated with carbon monoxide
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Buy sustainably caught, not imported, tilapia whenever possible
Choosing optimally fresh tilapia from the start prevents many texture and color problems down the line.
Proper Storage to Inhibit Green Coloration
To keep your tilapia from developing a green tint over time:
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Keep fresh tilapia on ice until ready to cook
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Refrigerate immediately after purchase
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Use tilapia within 2 days of purchasing for optimal quality
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Don’t refreeze thawed tilapia – cook within 1-2 days
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If freezing raw tilapia, use it within 3 months for best texture
Proper storage temperature is key to preventing bacterial growth that makes tilapia appear green and inedible. Handle with care.
Cooking Tips for Green Tilapia
If your tilapia already has a slight greenish cast, use these tips to make it tasty and safe:
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Rinse thoroughly to remove any gallbladder fluid
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Marinate in an acidic mixture like lemon or lime juice
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Use bold seasonings like paprika, cayenne, or blackening spice
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Cook to 145°F to eliminate bacteria – use a meat thermometer
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Sear, grill, or pan fry over high heat to intensify flavors
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Avoid boiling or steaming – this can intensify unpleasant flavors
With flavorful ingredients and the right techniques, you can mask any off-putting colors or tastes.
Preventing Green Tilapia in the Future
To avoid winding up with unappetizing green tilapia in the future:
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Source tilapia from reputable, sustainable fisheries
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Reject frozen fish treated with carbon monoxide
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Check for signs of freshness like clear eyes, red gills, firm flesh
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Rinse the fish well and remove all traces of gallbladder fluid
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Cook tilapia within 2 days of purchase for best quality
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Store properly at 33-40°F until ready to cook
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Freeze raw tilapia for up to 3 months maximum
With these preventative measures, you can enjoy delicious, non-green tilapia every time.
The Takeaway on Green Tilapia
While not inherently dangerous, greenish tilapia is far from appetizing. With the right selection, storage, and preparation, you can avoid this unappealing color change and enjoy the full delicious flavor of fresh tilapia. Check for firmness, freshness, proper handling, and signs of spoilage to source the best fish. Then cook your tilapia right away with bold seasonings, high heat, and proper food safety. With these tips, you can master tilapia texture and keep those unappetizing green fillets off your dinner plate.
Is green pond water bad for fish?
FAQ
What color is spoiled tilapia?
Is yellow tilapia safe to eat?
What color is tilapia raw?
Why is my tilapia red?
A fish treated with CO will usually appear bright red in color (as pictured above) and some mistakenly think that this means the fish is more fresh, though often that is far from the truth. The practice of using carbon monoxide is deceptive to you, the consumer, and is most commonly found in frozen Tilapia from China, Vietnam and Thailand.
Is it safe to eat talapia fish?
Tilapia fish is a low-calorie source of protein. In addition, tilapia fish contains vitamins and minerals such as folic acid and phosphorus. However, tilapia fish contains omega 6, which is relatively high, higher than omega 3. Ideally, omega 3 and 6 have a ratio close to 1:1. Excessive consumption of foods high in omega 6 is at risk of increasing inflammation. In addition, it is also essential to know the process of cultivating tilapia fish to avoid harmful bacteria such as Salmonella or other harmful substances that may arise during cultivation.
Why does frozen tilapia turn brown?
How to Tell Not many people are aware, but imported, frozen Tilapia is often treated with carbon monoxide (CO). This process is sneaky as it can help the fish look fresher for longer by delaying the oxidization of the meat, which is what causes fish to turn brown as it spoils.
Why does tilapia smell bad?
The bad odor indicates that there is increased bacteria growth in the fish, and the flesh has started to break down, and there is a high risk that you would become sick with food poisoning if you eat the tilapia. So, to be safe, discard any tilapia that has a very strong fishy smell, or a bad odor.