Fish and Seafood

Fact Sheets

Blue Mussels

Blue Mussels
Moules bleues
Mytilus edulis
Miesmuschel
Mejilón

Distribution and Seasons

Blue mussels, now the product of a very successful aquaculture industry, are available year round throughout Canada's Atlantic provinces. The industry is concentrated in Prince Edward Island, but mussel farms are flourishing in New Brunswick, Quebec, Nova Scotia, and especially, Newfoundland. A mussel industry is also developing on Canada's Pacific Coast, off the province of British Columbia.

Cultured blue mussels have a smooth, bluish black shell curved in a distinctive "D" shape. The inside of the shell is pearly violet or white. Projecting out from between the shells on one side is a bundle of tough, brown fibres called the byssal threads, more commonly known as the beard. Mussels use these fibres to anchor themselves.

Cultured mussels are grown in mesh stockings that are suspended from longlines (ropes) in the water. These ropes are anchored at the bottom and suspended using a brightly coloured lobster buoy for a float.

The clean, cold waters of the north Atlantic and Pacific oceans provide the ideal habitat for blue mussels. Because they never touch the ocean bottom and because they feed off the nutrient-rich water that surrounds them, cultured mussels taste sweeter, are plumper and more tender, have thinner shells, and consequently, a higher meat yield than their wild counterparts. Additionally, they are free of the grit that often spoils the taste of these filter feeders when they are harvested from the bottom.

Sustainability & Harvest

Canadian mussels grow naturally, feeding on the natural nutrients present in the sea. Mussels spawn during the months of June and July, and each mussel may produce up to 20 million eggs. Once fertilization has occurred, development takes place rapidly. After several weeks, the larva develops a functional foot and then an "eyespot," a small black speck thought to be photosensitive. When the eyespot appears, it is a signal that a larva is about to settle on a suitable substrate and become a juvenile mussel or "spat."

Mussel farmers put out ropes or other collectors of various types to collect the spat. After 10-12 months of growth, the mussel collectors are stripped of their spat, size sorted, and then transferred into lengths of mesh tubing called socks which are hung from long lines for final grow-out to market size. This can take anywhere from 18 months to three years, depending on location, water temperature, and the availability of plankton. Size at harvest is usually around 50mm (2 inches).

Mussel culture is benign and environmentally friendly. Rope culture allows mussels to be harvested easily by means of a winch and pulley on a boat. The ropes are pulled up so that the socks can be removed. Unlike the wild fishery, it is not necessary to drag the ocean floor to harvest the mussels.

Description

Mussels are bivalves, having two equally shaped shells linked together on one side by a hinge structure. Like most bivalves, mussels are filter feeders. They eat by pumping water through a set of gill filaments which filter out small particles such as phytoplankton, zooplankton and other organic material. Sediment is discharged while food is retained and passed into the stomach where it is digested. Mussels are able to obtain all of their nutritional requirements from the natural environment and do not require additional feeding.

Mussels are the most efficient feeders of all shellfish, containing one-third more protein than oysters. A mussel will filter 10-15 gallons of water a day, consuming virtually everything in it.

As well as being tasty, blue mussels are nutritious. They are particularly rich in protein and minerals while being low in fat, sodium and cholesterol. A 100 g (3.5 oz) serving of mussel meats provides 23% of the daily recommended amount of Vitamin C and 37% of iron. One serving of mussels provides close to 100% of the daily recommended intake of zinc, promoting good growth, brain function, and enhanced immunity against colds and flu. Mussels also deliver a respectable amount of omega-3 fatty acids, believed to protect against heart disease and help relieve inflammatory diseases.

Nutritional Profile (per 100 grams or 3.5 oz cooked meat)

Energy	95kcal 397kj
Protein	14.4g
Fat	2.2g
Carbohydrates	3.3g
Sodium	289mg
Cholesterol	28mg
Omega 3	0.4g

Source: Province of New Brunswick

Product Forms

Cultured blue mussels are available live, frozen, or in value-added preparations. Once harvested, the mussels are kept in live holding tanks prior to processing. Machines clean the shells, remove the byssal threads, and grade the mussels which are then hand inspected and either packed for shipping, or transferred for secondary processing.

Most live mussels are packed in mesh bags (ranging from 2 lbs to 25 lbs), but recently some processors are packing live mussels in Modified Atmosphere Packaging (MAP), a process that uses a special oxygen/carbon dioxide mix to to extend the shelf-life of live mussels.

There are an increasing number of value-added mussel products on the market as well. Whole, in-shell mussels in a variety of sauces, frozen and vacuum-packed is currently one of the most popular ready-to-eat items, but there are mussel salads available in deli cases, smoked mussels in cans, and marinated mussel meats in jars. As this industry grows and expands further, there will be many more new products for consumers to enjoy.

Storage

Live mussels cannot be kept in plastic or in sealed containers. They should be stored at temperatures just above freezing (1-2 degrees C. or 34-36 degrees F). Store in open containers that allow for draining and never store in direct contact with melted ice or water. Broken mussels or those that do not close when tapped should be discarded. The less they are disturbed, the longer the mussels will last.

Preparation

A very versatile food, mussels can be steamed, baked, deep-fried, pan-fried, battered, smoked or pickeled. They can be used in soups, chowders, salads, paellas, casseroles, in pasta dishes, or in hors-d'oeuvres and canapés. Likely the most famous mussel dish, recognized world-wide, is moules marinières, mussels steamed in white wine with herbs.

When steaming mussels, it is only necessary to cook them until the shells open wide and the meats become loose from the shell, about 5-7 minutes. Overcooking will cause the meats to become tough and dry.

Mussel meats have different colours. Males and immature females are pale white while mature females are a yellowish-rust colour.

Safety and Wholesomeness Assured

Canada has one of the world's most respected fish inspection and control systems. The Canadian Food Inspection Agency (CFIA) sets the policies, requirements and inspection standards for fish products, federally registered fish and seafood processing establishments, importers, fishing vessels, and equipment used for handling, transporting and storing fish. All establishments which process fish and seafood for export or inter-provincial trade must be federally registered and must develop and implement a HACCP-based Quality Management Program (QMP) plan. A processing establishment's QMP plan outlines the controls implemented by the fish processor to ensure that all fish products are processed under sanitary conditions, and that the resulting products are safe and meet all regulatory requirements. Canada's fish-inspection and control system contributes to Canada's worldwide reputation for safe, wholesome fish and seafood products.

Mussels, like clams, oysters and other sedentary filter feeders, are susceptible to water-borne toxins. While not dangerous to the molluscs, these toxins can be potentially deadly to humans. The Canadian Food Inspection Agency, together with Environment Canada and Fisheries and Oceans Canada, administers the Canadian Shellfish Sanitation Program (CSSP) which is designed to ensure that the growing areas of all bivalve molluscs meet approved federal water quality criteria and that all shellfish sold commercially are harvested, transported and processed in an approved manner.

All blue mussels from Canada are tagged with the date and place of harvest. Retailers and foodservice operators cannot co-mingle product from different bags, and must keep bag tags and updated log books for reference.

Suppliers

List of Canadian blue mussel suppliers

NOTE: These processors are volume wholesalers and are not usually set up to deal directly with consumers.

Related Sites

• Prince Edward Island Department of Fisheries, Aquaculture and Environment
• Newfoundland Department of Fisheries and Aquaculture
• New Brunswick Department of Agriculture, Fisheries and Aquaculture
• Nova Scotia Department of Agriculture and Fisheries
• Québec Ministry of Agriculture, Fisheries and Food
• Prince Edward Island Aquaculture Alliance
• Newfoundland Aquaculture Industry Alliance
• Canadian Aquaculture Industry Alliance