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length and may occasionally reach 165 mm. Its shell ends in a downward-pointing
beak. The smooth periostracum is dark green, becoming increasingly brownish
towards its point of attachment (umbo), where it is lighter. The Asian green mussel
is found in the coastal waters of the Indo-Pacific region. However, the mussels are
introduced to other areas as invasive species via boat hulls and water ballasts. The
mussels live in waters that are 11–32 °C with a wide-ranging salinity of about
18–33 ppt. P. viridis is harvested in the Indo-Pacific region as a food source due to
its fast growth. However, it can harbour deadly Saxitoxin produced by the dinoflagellates that it feeds upon. It can also be used as a bio monitor to indicate pollution
caused by heavy metals, organochlorides, and petroleum products (Wikipedia 2019c).
The green mussel Perna viridis has the most widespread distribution, extending
from India eastwards to south-east Asia, the China coast, Indonesia, Philippines,
and Samoa. The species is a recent invader to the Caribbean Sea, including the subtropical south-eastern United States region (Gosling 2015).
Perna perna (Linneaeus, 1758) (Brown Mussel)
Perna perna, the brown mussel, is an economically important mussel, a bivalve
mollusc belonging to the family Mytilidae. It is harvested as a food source but is
also known to harbour toxins and cause damage to marine structures. It is native to
the waters of Africa, Europe, and South America and was introduced in the waters
of North America. Perna perna is usually 90 mm long although it can reach sizes of
up to 120 mm. The mussel is easily recognized by its brown colour, but its identifying characteristic is the “divided posterior retractor mussel scar”. Its pitted resillal
ridge also differentiates the mussel from other bivalves. The brown mussel is native
to the tropical and sub-tropical regions of the Atlantic Ocean. It is found in waters
off the west coast of Africa and the coast of South America up to the Caribbean. It
is accidentally introduced as an invasive species to the coast of Texas via the boat
hulls and water ballasts of ships from Venezuela. Its distribution includes Chile,
Peru, and South Africa (Wikipedia 2019d).
Nutritive Composition of Mussels
Mussels are an important source of nutrients containing essential nutrients and are
preferred as an inexpensive protein source for human consumption, especially in
countries with low socioeconomic levels. Since shellfish are low in fat, especially
low in saturated fat, containing omega-3 fatty acids, excellent protein sources and
particularly good sources of iron, zinc, copper and vitamin B 12 , increasing the intake
of various shellfish should be encouraged to ensure a healthy diet (Dong 2001)
(Tables 3.1 and 3.2). Mussels are an environmentally sustainable way of producing
dietary protein and long-chain omega-3 fatty acids. Mussels are not only a sustainable source of omega-3 fatty acids, but also a sustainable source of essential amino
acids. The protein content in mussels varies between 12.6 and 24.0 g/100 g mussels,
depending on the variety. Mussels contain a range of vitamins and minerals found
3 Molluscan Shellfish
length and may occasionally reach 165 mm. Its shell ends in a downward-pointing
beak. The smooth periostracum is dark green, becoming increasingly brownish
towards its point of attachment (umbo), where it is lighter. The Asian green mussel
is found in the coastal waters of the Indo-Pacific region. However, the mussels are
introduced to other areas as invasive species via boat hulls and water ballasts. The
mussels live in waters that are 11–32 °C with a wide-ranging salinity of about
18–33 ppt. P. viridis is harvested in the Indo-Pacific region as a food source due to
its fast growth. However, it can harbour deadly Saxitoxin produced by the dinoflagellates that it feeds upon. It can also be used as a bio monitor to indicate pollution
caused by heavy metals, organochlorides, and petroleum products (Wikipedia 2019c).
The green mussel Perna viridis has the most widespread distribution, extending
from India eastwards to south-east Asia, the China coast, Indonesia, Philippines,
and Samoa. The species is a recent invader to the Caribbean Sea, including the subtropical south-eastern United States region (Gosling 2015).
Perna perna (Linneaeus, 1758) (Brown Mussel)
Perna perna, the brown mussel, is an economically important mussel, a bivalve
mollusc belonging to the family Mytilidae. It is harvested as a food source but is
also known to harbour toxins and cause damage to marine structures. It is native to
the waters of Africa, Europe, and South America and was introduced in the waters
of North America. Perna perna is usually 90 mm long although it can reach sizes of
up to 120 mm. The mussel is easily recognized by its brown colour, but its identifying characteristic is the “divided posterior retractor mussel scar”. Its pitted resillal
ridge also differentiates the mussel from other bivalves. The brown mussel is native
to the tropical and sub-tropical regions of the Atlantic Ocean. It is found in waters
off the west coast of Africa and the coast of South America up to the Caribbean. It
is accidentally introduced as an invasive species to the coast of Texas via the boat
hulls and water ballasts of ships from Venezuela. Its distribution includes Chile,
Peru, and South Africa (Wikipedia 2019d).
Nutritive Composition of Mussels
Mussels are an important source of nutrients containing essential nutrients and are
preferred as an inexpensive protein source for human consumption, especially in
countries with low socioeconomic levels. Since shellfish are low in fat, especially
low in saturated fat, containing omega-3 fatty acids, excellent protein sources and
particularly good sources of iron, zinc, copper and vitamin B 12 , increasing the intake
of various shellfish should be encouraged to ensure a healthy diet (Dong 2001)
(Tables 3.1 and 3.2). Mussels are an environmentally sustainable way of producing
dietary protein and long-chain omega-3 fatty acids. Mussels are not only a sustainable source of omega-3 fatty acids, but also a sustainable source of essential amino
acids. The protein content in mussels varies between 12.6 and 24.0 g/100 g mussels,
depending on the variety. Mussels contain a range of vitamins and minerals found
3 Molluscan Shellfish