they are also eaten by humans. anchovies preserved by being gutted and salted in brine, matured, then packed in oil, are an important food fish, both popular and infamous for their strong flavor. in roman times, they were the base for the fermented fish sauce called "garum" that was a staple of cuisine and an item of long-distance commerce produced in industrial quantities. today they are a key ingredient in caesar salad and spaghetti alla puttanesca, and are often used as a pizza topping. because of the strong flavour they are also an ingredient in several sauces, including worcestershire sauce and many fish sauces, and in some versions of café de paris butter. they are most commonly marketed in small tins, either as "flat" filets, or as "rolled anchovies" where each fillet is rolled around a caper. both are quite salty. the flat fillets are usually more salty than the rolled anchovies. they are also marketed in jars and tubes as a paste, mostly for use in making sauces, such as anchovy essence. fishermen also use anchovies as bait for larger fish such as tuna and sea bass.