scalloped oysters 5 1 4 1 2 1 . Sam Sifton’s email newsletter to readers of Cooking with recipe suggestions and food tips.
Sign up here to get it in your inbox. Sam Sifton is an assistant managing editor of The New York Times, responsible for culture and lifestyle coverage, and the founding editor of New York Times Cooking. Since arriving at The Times in 2002, he has served as food editor, culture editor and national editor, and worked as the restaurant critic and a columnist for The New York Times Magazine. For potato scallops, see Potato cake.
For the cut of meat, see Escalope. Scallops are a cosmopolitan family of bivalves which are found in all of the world’s oceans, although never in fresh water. They are one of very few groups of bivalves to be primarily “free-living”, with many species capable of rapidly swimming short distances and even of migrating some distance across the ocean floor. Many species of scallops are highly prized as a food source, and some are farmed as aquaculture. The word “scallop” is also applied to the meat of these bivalves, the adductor muscle, that is sold as seafood.
Owing to their widespread distribution, scallop shells are a common sight on beaches and are often brightly coloured, making them a popular object to collect among beachcombers and vacationers. The shells also have a significant place in popular culture, including symbolism. Scallops inhabit all the oceans of the world, with the largest number of species living in the Indo-Pacific region. Most species live in relatively shallow waters from the low tide line to 100 m, while others prefer much deeper water. Although some species only live in very narrow environments, most are opportunistic and can live under a wide variety of conditions.
Very little variation occurs in the internal arrangement of organs and systems within the scallop family, and what follows can be taken to apply to the anatomy of any given scallop species. The shell of a scallop consists of two sides or valves, a left valve and a right one, divided by a plane of symmetry. Scallops are filter feeders, and eat plankton. Unlike many other bivalves, they lack siphons. Water moves over a filtering structure, where food particles become trapped in mucus. Next, the cilia on the structure move the food toward the mouth.
Like all bivalves, scallops lack actual brains. Instead, their nervous system is controlled by three paired ganglia located at various points throughout their anatomy, the cerebral or cerebropleural ganglia, the pedal ganglia, and the visceral or parietovisceral ganglia. The visceral ganglia are also the origin of the branchial nerves which control the scallop’s gills. The cerebral ganglia are the next-largest set of ganglia, and lie distinct from each other a significant distance dorsal to the visceral ganglia. They are attached to the visceral ganglia by long cerebral-visceral connectives, and to each other via a cerebral commissure that extends in an arch dorsally around the esophagus. These eyes represent a particular innovation among molluscs, relying on a concave, parabolic mirror of guanine crystals to focus and retro-reflect light instead of a lens as found in many other eye types. These muscles lie closely apposed to one another but are divided by a connective tissue sheet.
Scallops are mostly free-living and active, unlike the vast majority of bivalves, which are mostly slow-moving and infaunal. All scallops are thought to start out with a byssus, which attaches them to some form of substrate such as eelgrass when they are very young. Most species lose the byssus as they grow larger. Most species of the scallop family are free-living, active swimmers, propelling themselves through the water through the use of the adductor muscles to open and close their shells.
Swimming occurs by the clapping of valves for water intake. Closing the valves propels water with strong force near the hinge via the velum, a curtain-like fold of the mantle that directs water expulsion around the hinge. Other species of scallops can be found on the ocean floor attached to objects by byssal threads. Byssal threads are strong, silky fibers extending from the muscular foot, used to attach to a firm support, such as a rock. Some can also be found on the ocean floor, moving with the use of an extendable foot located between their valves or burrowing themselves in the sand by extending and retracting their feet. Seasonal changes in temperature and food availability have been shown to affect muscle metabolic capabilities. The properties of mitochondria from the phasic adductor muscle of Euvola ziczac varied significantly during their annual reproductive cycle.
Summer scallops in May have lower maximal oxidative capacities and substrate oxidation than any other times in the year. This phenomenon is due to lower protein levels in adductor muscles. Scallops do occasionally produce pearls, though scallop pearls do not have the buildup of translucent layers or “nacre” which give desirability to the pearls of the feather oysters, and usually lack both lustre and iridescence. Some scallops, including Chlamys hastata, frequently carry epibionts such as sponges and barnacles on their shells. In fact, barnacle encrustation negatively influences swimming in C.