Prawns arouse contradictory feelings. They are crustaceans known for the exquisiteness of their meat, but at the same time they are viewed with some distrust due to their status as scavenger marine animals. Be that as it may, crustaceans are consumed in large quantities in our country: they number in thousands of tons per year and are the protagonists of numerous culinary recipes.
We know that crustaceans in general are one of the foods with the highest cadmium content, a heavy mineral found in the dark meat of these animals, where arthropods and mollusks have the pancreas, the digestive system; that is, in the head. That is why the Spanish Food Safety Agency recommends that they not be sucked excessively frequently and that they also not be used to make fumet.
But what happens with the black thread that comes out of the head and runs through the entire abdominal part of the shrimp to the tail? For nutritionist Beatriz Robles, "beyond knowing that we are eating the digestive tract and the remains that may be present, it does not represent any danger," unlike other parts of this food, such as the head, which is where the higher levels of cadmium.
But we must bear in mind that, depending on the level of cooking of the shrimp, this black thread can alter the flavor of the meat. There are those who detect a bitter taste that harms the product, so it is sometimes recommended to remove it.
The nutritionist recommends avoiding raw consumption, since "we are more exposed to pathogenic microorganisms and we have a greater risk that certain bacteria can access our body." This danger disappears when we boil food.
In addition, this thread is also the reason why we can sometimes ingest remains of sand when we eat a crustacean. As has been said, they are animals that concentrate in the depths and that take advantage of the remains of other beings found on the seabed. Due to the way they eat, they can introduce mud and sand into the body.
This dark filament is also usually removed for aesthetic reasons: many cooks choose to remove the digestive tube of these crustaceans because, beyond the flavor, it visually contrasts with the white or grayish color of the body.
The black thread can be easily removed with your fingers once the shrimp has been peeled. All you have to do is stretch it from the front or, if it is not visible, from the tail. And if we don't have access from either end, we can make an incision halfway up the spine with a toothpick or similar tip and we will surely be able to remove it.
Read the original RAC1 article here.
