Tuna meat is red, but the shade of red is what dictates its color score, the deeper the red and the more translucent the meat, the higher the quality (this is often referred to as color and clarity).. Texture - the finer the better. #1 grade tuna should have a fine and smooth texture, it should not be coarse or grainy.
Bright red or pink tuna means it has been gassed. In its natural state, fresh tuna is dark red, almost maroon, sometimes even chocolatey looking. Don't worry, you most likely will have no ill effects from eating gassed tuna, according to the FDA.
Unopened canned tuna lasts for years past the printed date as long as the can stays intact. The tuna retains best quality for 3 to 5 years of canning, but stays safe way past that period.
Regardless if it's yellowfin, bigeye or bluefin, #1 tuna must exhibit high fat. The presence of fat will appear as marbling in the meat and near the skin. The texture will have a sticky feel to it and the color should be red, shiny and translucent. This is the best grade for all raw applications - sushi, crudo, etc.
When checking the nutrition labels, make sure that you're buying “light” tuna because it comes from skipjack tuna, which is lower in mercury. *Avoid getting yellowfin tuna which is a higher mercury level fish. Check the packaging: As a rule of thumb while shopping for anything canned, I go for BPA-free ones.
Albacore is firm and meaty, with a light, mild flavor. Yellowfin and skipjack are a bit softer and have a richer, more intense taste. The choice comes down to personal preference: If you like a less “fishy” tuna experience, go for white tuna; if you want stronger flavor, light tuna is a better choice.
There should be a hint of salty seawater, and the overall mouth-feel should be clean. However, if the tuna steak tastes sour, mushy, or oily, it has most likely spoiled, and should be discarded immediately – do not swallow, as consuming spoiled tuna can lead to illness.
Tuna should not be kept for more than a few days in the fridge. Fresh tuna can last up to two days while canned tuna can last up to 3-4 days. If you need to store it longer, freeze it and label it so you know when it was frozen.
Unopened cans of tuna should be stored at room temperature, away from heat sources. Once opened, leftovers should be placed in an airtight container and refrigerated for 3-5 days.
Tuna tends to oxidize quickly, which cause it to turn an unappetizing grey or brown. Even though it may still be relatively fresh at that point, no one wants to eat it because of the way it looks.
Tuna meat is red, but the shade of red is what dictates its color score, the deeper the red and the more translucent the meat, the higher the quality (this is often referred to as color and clarity)..
Foodiosity also notes that tuna with more myoglobin, and therefore a redder hue (like Atlantic bluefin), can be substantially more flavorful than lighter colored varieties (like Albacore).
The effect of treating fish such as tilapia, some species of which are colored red, with carbon monoxide — tuna is another species commonly “gassed” with CO — prevents the flesh from turning bright red to brown as the flesh ages. And this is where the consumer is conned.
The “dark part” is is from the abdominal region and known as “black tuna”. It is largely regarded as a waste byproduct due to its strong, fishy flavor and aroma.
So, how long does tuna last in the fridge? If properly stored (in an airtight container), fresh tuna can be kept in the refrigerator for up to 2 days. Similarly, if continuously refrigerated, an opened canned tuna will stay fresh for about 3-4 days.
Tuna fish has a fairly strong smell to begin with, so if you smell something off, it's best to toss it out rather than take the risk. Even if there's no discoloration or off smell, if your tuna salad has been sitting in the fridge for more than 5 days, you should toss it out.
If you need to store it, pat it dry, wrap securely in plastic wrap or foil and store in the coldest part of your refrigerator (optimum temperature of 31 F). If your refrigerator is not that cold, place the wrapped fish on a bed of ice or in a plastic bag filled with ice.
Shelf Life Tips
To maximize the shelf life of canned tuna (or tuna sold in a vacuum-sealed pouch) after opening, refrigerate in a covered glass or plastic container. How long does opened canned tuna last in the refrigerator? Tuna that has been continuously refrigerated will keep for about 3 to 4 days.
Manufacturers know this, so canned tuna is precooked whole before it is processed. And then it is cleaned, separated and cooked again once inside the can. This process is necessary to kill bacteria, but it also sometimes causes the creation of a histamine that can give the canned tuna that “fishy” smell.
Scombroid fish poisoning resembles an allergic reaction and occurs within minutes to hours of eating fish contaminated with histamine. The most common symptoms are rash, diarrhea, reddening or flushing of the face and sometimes the neck, arms, and upper part of the body, sweating, headache, and vomiting.
Selecting and purchasing fish and seafood
Fish tastes "fishy" when it hasn't been handled properly. To avoid "fishy" fish, smell and feel it. It should have a fresh and mild odor. It should be firm to touch and "spring back" into place.
The FDA recommends consuming fish lower in mercury. For tuna varieties, skipjack earns the Best Choice label from the FDA, while yellowfin and albacore receive the Good Choice label. The FDA suggests avoiding bigeye tuna, which has the highest levels of mercury.
NON SUSHI GRADE Tuna is OK to eat tune blue-rare, but salmon is best rare-medium rare and white fish should be cooked medium-well done. All fish is safe to eat COMPLETLY raw if it is sushi grade.