What are
The cockles are Bivalve molluscs (lamellibranchs) belonging to the Order of Veneroidae and the Tellinoidea Superfamily. However, the term "telline" could be attributed 2 distinct meanings:
- BIOLOGICAL: Bivalve organisms belonging to the Tellinidae family and to the genus Tellina
- COMMON: Bivalve organisms belonging to the family Donacidae, to the genus Donax and to the 5 species widespread in our seas, of which the main one is undoubtedly the trunculus (the others are: vittatus, variegatus, semistriatus, venustus ).
Description, Distribution, Ecology
The cockles are presented with a cuneiform, solid shell, composed of two valves. The front part is longer and the dorsal margin of the left valve always exceeds that of the right valve. The surface is smooth and has some growth lines. The external color (variable) is pale brown, with lighter radial stripes and darker growth lines; the inner surface is whitish.
Internally, to a profane eye, the mollusk vaguely resembles that of the clams. The cockles reach about 3 cm in length and 1.5 cm in height.
The cockles occupy the upper infralittoral plane of the temperate climate seas. In the Mediterranean Sea they are distributed mostly between 0 and 2 meters deep, while in the Atlantic Ocean they are available between 0 and 6 meters (they are also present in the Black Sea). The cockles have been classified as "characteristic and exclusive species of the Fine Sands of the High Levels".
The cockles have separate sexes and reproduce between spring and summer.
They are fast and excellent diggers. They do not make large movements and do not migrate. The cockles have a suspensive diet and feed mainly on organic material and phytoplankton.
The fishing takes place in a manner very similar to that of the clams. They are captured by means of dredging vessels or blowing turbines; obviously, since they are creatures that colonize the first few meters of depth, their professional withdrawal is more problematic and most of the times it is secondary to clam fishing. The amateur collection is carried out with manual sieves equipped with long handles.
Culinary aspects
Let's start by clarifying that tellins, similarly to many other bivalve molluscs, can be sold directly to the final consumer ONLY in the event that seawater is considered safe from the point of view of health and hygiene. On the contrary, like clams, they require purification in housing systems that, in addition to ensuring the reduction of the hygienic risk, favor the expulsion of the sand from inside the animal.
The clams must necessarily be marketed alive; this condition is easily recognizable by the closing of the valves which, in the event of death, are spaced. Even the mass of the mollusc is an excellent indicator of freshness; if the cockles die they open the valves and, in doing so, they are emptied of the water enclosed within them. Without this liquid, a bag of cockles can weigh almost 50% less. NB . If the cockles are alive, immersed in salted water (4% NaCl) they must open slightly and eject the foot. It is also very important to check the integrity of the shells; the clam clams (more similar to razor clams) tend to splinter and are not as resistant as those of mussels, clams, oysters, fasolari, canestrelli, sea truffles or scallops. This characteristic must be kept in mind when cooking; the cockles should therefore be stirred / sautéed very gently.
The cockles are used in numerous recipes based on fishery products. They are excellent with gnocchetti and fresh egg tagliolini. They represent a superfine ingredient since it is not widespread; the value of preparations such as spaghetti allo scoglio, paella, risotto with seafood, etc. is increasing. The cockles also lend themselves to the composition of mixed raw vegetables, opened by a good paring knife, served naturally or seasoned with fresh lemon juice. The favorite wine in the accompaniment of the various cooked dishes based on tellins is Verdicchio dei Castelli di Jesi; for crudités instead, one could opt for a DOC prosecco.
Nutritional aspects
Let us once again remember that cockles are potential microbiological vehicles, especially if caught in waters of dubious healthiness. The presence of hepatitis A virus and other bacteria is not to be excluded, among which above all: faecal coliforms, salmonella (typhoid or not) and cholera vibrios. For this reason, raw cockles are to be excluded from feeding the pregnant woman. Furthermore, due to the statistical risk of allergy to certain molluscs, cockles (even cooked) are unsuitable for very young children.
Not enough detailed information is available on the nutritional intake of cockles. Probably also their chemical profile (like that of mussels, oysters, etc.) varies according to the season and should be richer in the reproductive spawning phase (spring and summer). Being of animal origin, cockles contain cholesterol but the profile of fatty acids (hypothetically good) should not excessively limit their consumption. For subjects suffering from hypercholesterolemia, it is however advisable to consume them sporadically (eg once a week) and in small portions. The cockles also contain high amounts of sodium, a mineral salt to be taken with caution, especially in the presence of hypertension. Proteins should have a high biological value and almost no carbohydrates. It is not possible to establish what are the vitaminic and saline benefits of eating cockles.
Bibliography:
- Donax trunculus (bivalvia: Donacidae) as a biological indicator of coastal equilibrium and sedimentary balance - Paola La Valle - Rome, 2005 - doctoral school in ecological sciences University of Rome "la sapienza" XVIIIth cycle (2002-2005).
