No wonder there’s confusion regarding the difference between anchovies and sardines. Both are members of the herring family, both benefit from the same cooking techniques and both are an excellent source of Omega-3 oils and calcium. To the untrained eye, they both look like small silver fish. But fans of the finfish know that these flavorful—albeit similar—species each has its own unique appeal.

Anchovies. Almost every country boasts an “anchovy,” but it’s rarely the same fish. From the Latin names engraulis (Mediterranean) and Anchoa (North American); there are several of each species. The true anchovy hails from the Mediterranean. Anchovies travel in dense schools, mingling with other small fish, providing the makings of whitebait with the scoop of the net.

Most anchovies are canned or exported, where they are salted, smoked, pounded into paste or distilled to make the fish sauces of Southeast Asia.

Canned anchovies are sold flat or rolled, and can be stored at room temperature for at least a year. Once opened, they can be refrigerated, sealed, for at least two months. To lessen anchovies’ saltiness, soak them in cool water for 30 min.; pat dry.

Salt-packed anchovies are sold whole with bones and offer the purest (least salty) flavor. To clean them, rinse under running water and pull off fins. Use your finger to separate the fish into two fillets. The bone will adhere to one of the fillets, but it is easily pulled away.

Anchovy paste is a combination of pounded anchovies, vinegar, spices and water. It comes in a tube, making it convenient for cooking.

Sardines. Sardine is a generic term applied to small, soft-boned, saltwater fish such as herring, sprat and young pilchard. Canned sardines from the U.S. and Canada are Atlantic herring; from Norway they are the sprat. The silvery, iridescent fish swim in huge schools.

Fresh sardines are available during the summer. Atlantic herring (Clupea harengus harengus) is found across the North Atlantic; Pacific herring (C. Harengus pallasi) range from northern California to Alaska and from Eastern Russia south to Japan.

Fresh sardines must be gutted. To do this, pinch the gills at the base of the head, and pull them out. Slide a finger along the belly cavity and pull out the innards; rinse under cold water. Gutting is easier if you remove the heads. Simply snap back the head and pull it off; the guts should come with it. Sardines can also be gutted and boned through the back—ideal for stuffing and baking.

Sardines lend themselves to simple cooking methods, such as grilling, baking, in escabeche, hot-smoking, broiling and pan-frying. Avoid long-simmering sardines; the flavor is too strong and the flesh will fall apart.

Fresh, whole herring should be bright-skinned with hard bellies. Smaller herring have a delicate flavor; larger fish have a fuller, oilier taste.

In the U.S., sardines are salted, smoked or canned, in oil, tomato or mustard sauce.

• Good quality canned anchovies are firm and not fishy.
• One sure way to tell the difference between the two fish: The lower jaw of sardines protrudes farther than the top. Anchovies have the reverse trait—the top jaw protrudes farther than the lower.
• Look for fresh herring in spring and summer, just before spawning, when they have the highest fat content and are the best quality.
• When buying marinated herring, check for net weight, not just the size of the container.
• Anchovies and sardines become rancid pretty quickly, and begin to smell as they deteriorate. Look for relatively firm, unbruised fish with shiny skin and bright eyes.