Rollmops

Rollmops ( listen ) are pickled herring fillets, rolled into a cylindrical shape, often around a savoury filling.

The filling is usually slices of pickled gherkin, or green olive with pimento. Rollmops can be served held together with one or two small wooden skewers.

Rollmops are usually bought ready-to-eat, in jars or tubs. The marinade additionally contains water, white vinegar, and salt; it may also contain sugar or other sweetening agents, onion rings, peppercorns and mustard seeds. Rollmops can be eaten cold, without unrolling, or on bread. After the jar has been opened, they will usually keep for two to three weeks if kept cool or refrigerated. Rollmops are sometimes served with Labskaus.

The name "rollmops" is German in origin, derived from the words rollen (to roll) and Mops (German name of pug dogs, but also "blockhead"). The form Rollmops is singular, and the plural is Rollmöpse.

In English, the term "rollmops" is often treated as the plural of the singular "rollmop". The form "rollmop herrings" is also attested.

Pickled herrings have been a staple in Northern Europe since Medieval times, being a way to store and transport fish, especially necessary in meatless periods like Lent. The herrings would be prepared, then packed in barrels for storage or transportation.

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Wikipedia