What are Mussels?

You might know mussels as a humble shellfish, a bivalve or a classic ingredient in many dishes. However you describe them, they’re one of the ocean’s true treasures. Whether steamed in garlic wine broth or served in a seafood feast, mussels add wonderful flavour to any seafood dish.

Even though mussels are common on restaurant menus, many people don’t know much about them. In this guide, we’ll look at what mussels are, how they taste and their role in traditional coastal cooking.

What Kind of Animal Are Mussels?

Mussels are marine invertebrates from the mollusc family, known as bivalve molluscs because they have two hinged shells. They live in both saltwater and freshwater, attaching themselves to rocks or piers with strong, silky byssus threads.

Inside their dark, oval shells is a soft, edible body that can range in colour from pale cream to deep orange. Mussels are natural filter feeders, drawing in water to eat microalgae and plankton. This helps keep coastal waters clean and healthy.

Are Mussels a Fish?

Even though mussels are often listed as seafood on menus, they’re not fish. Fish have backbones, fins and gills to swim in open water. Mussels are invertebrate shellfish, so they have no bones and are protected by their hard shells.

Mussels are more closely related to animals like squids, snails and octopuses than to fish such as cod or salmon. Still, they are a highlight on many top seafood restaurant menus.

How Do Mussels Differ from Clams and Oysters?

These soft-bodied sea creatures may look alike, but they aren’t from the same biological family. Each bivalve has a hinged shell with two halves that protect its soft inside. Mussels, clams and oysters all belong to the phylum Mollusca and the class Bivalvia. After that, though, they split into different families.

Mussels are part of the Mytilidae family, while oysters belong to the Ostreidae family. Clams are more varied and can be found in several families, such as Veneridae and Mactridae. Over time, each type has developed its own way to survive in the ocean. Mussels use strong threads to attach to surfaces, oysters make a natural cement to stick to rocks and clams use a muscular foot to dig into sand.

You can tell these three types of shellfish apart by looking at their shape, colour, texture and taste.

• Mussels have long, teardrop-shaped shells that are usually dark blue or black. They taste mildly sweet and have a plump, tender texture.
• Clams have round or oval shells that are smooth and lighter in colour. They are sweeter, firmer, and chewier, with a strong briny flavour.
• Oysters have thick, rough, and uneven shells with jagged edges. They offer a bold, salty, and mineral-rich flavour.

What Do Mussels Taste Like?

Mussels have a delicate, mildly sweet taste with a fresh, salty finish. When cooked well, they turn tender and plump, giving a satisfying bite without being chewy or rubbery.

Because their flavour is subtle, mussels easily take on the rich tastes of garlic, white wine, herbs and butter. This makes them great for both classic recipes and modern, creative dishes.

When Are Mussels in Season in the UK?

In the UK, people often say mussels are best in months with the letter ‘R’ in their name. From September to April, colder seas help mussels grow plump and flavourful. In summer, during spawning, their meat can be thinner and less ideal for fine dining. Thanks to modern rope-grown farming, high-quality mussels are now available in British harbours for most of the year.

A Sustainable Seafood Choice

Besides tasting great, mussels are one of the most sustainable protein sources you can buy. Farmed mussels grow naturally on ropes in the sea, so they don’t need artificial feed, chemicals or land to be cleared.

As they feed, mussels help clean the seawater around them, which benefits local marine life. By choosing farmed mussels, you can enjoy a delicious meal and make an environmentally friendly choice.

Enjoy Exceptional Seafood at Harbour House

Mussels are a real highlight of coastal dining, offering history, sustainability and great natural flavour. Whether you love seafood or are trying shellfish for the first time, using top-quality ingredients makes every meal better.

We take great pride in using fresh, high-quality ingredients to give you a remarkable dining experience by the water. Contact us to book a table today. Our menu has the best seafood the Southwest has to offer, including delicious west-country Mussels in a delicate chilli, garlic & lemongrass broth.