140
N. Koueta et al.
8.2.7 Enzyme
The fish-producing wastes represent an important source of proteins and enzymes,
especially digestive proteases, which are used in many applications in the food industry (Shahidi and Janak Kamil 2001; Gildberg et al. 2000), and other applications,
such as the detergent, pharmaceutical, leather and silk industries (Gupta et al. 2002).
The use of proteolytic enzymes is part of many traditional methods of fish treatment as fish sauces, canned, semi-preserved or salted fish. Protease constitutes an
important group of industrial enzymes, representing more than 65 % of the total
industrial enzyme market (Banik and Prakash 2004). All these processes depend
on varying degrees of activity of proteolytic enzymes associated with the viscera
themselves (Shahidi and Janak Kamil 2001) with digestive enzymes or other tissues
with cathepsins. Nowadays, enzyme-based technology represents an important contribution for many industrial applications. Aquatic invertebrates constitute natural
sources of enzymes with colossal interest, such as aspartic pepsin, serine proteases,
trypsin, chymotrypsin, collagenase, etc. Due to the prevailing environmental conditions, marine enzymes can effectively operate at low temperatures, below 4°C, and
within neutral to alkaline pH values. Enzymatic methods have become an important
and essential part of the processes used by the modern food and feed industry, to
produce a large and diverse range of products for human and animal consumption.
The aquatic environment contains the largest pool of genetic material and hence
has enormous potential for the sourcing of different enzymes (Shahidi and Janak
Kamil 2001). Cuttlefish wastes constitute an important source of proteolytic enzymes, particularly the digestive gland which contains a high number of proteinases (Hatate et al. 2000). Balti et al. (2009) extracted and purified trypsin from
the digestive gland of cuttlefish. A cysteine proteinase was partially purified from
the jumbo squid digestive gland (Cárdenas-López and Haard 2009). Hameed and
Haard (1985) recovered cathepsin C from the Atlantic short-finned squid digestive
gland. Some authors suggested that the salt-tolerant and exopeptidase activity of
this enzyme contributes to the pleasant flavour of fermented fish products (Shahidi
and Janak Kamil 2001).
8.2.8 Fish Sauce
Some of the potential uses of squid digestive gland proteinases are towards the preparation of fish sauce. The possibility of utilizing squid-processing by-products for
low-salt fish sauce production has been investigated since the 1980s (Lee et al. 1982;
Raksakulthai et al. 1986). Raksakulthai et al. (1986) showed the high potential of
squid digestive gland, containing proteolytic enzymes, which aid the fermentation
under optimal conditions.
Xu et al. (2008) concluded that squid by-products could be quickly fermented
into low-salt fish sauce with acceptable qualities in terms of aroma and nutrition.
Squid viscera have large and wide variety of uses in processed feeds and food sup-
N. Koueta et al.
8.2.7 Enzyme
The fish-producing wastes represent an important source of proteins and enzymes,
especially digestive proteases, which are used in many applications in the food industry (Shahidi and Janak Kamil 2001; Gildberg et al. 2000), and other applications,
such as the detergent, pharmaceutical, leather and silk industries (Gupta et al. 2002).
The use of proteolytic enzymes is part of many traditional methods of fish treatment as fish sauces, canned, semi-preserved or salted fish. Protease constitutes an
important group of industrial enzymes, representing more than 65 % of the total
industrial enzyme market (Banik and Prakash 2004). All these processes depend
on varying degrees of activity of proteolytic enzymes associated with the viscera
themselves (Shahidi and Janak Kamil 2001) with digestive enzymes or other tissues
with cathepsins. Nowadays, enzyme-based technology represents an important contribution for many industrial applications. Aquatic invertebrates constitute natural
sources of enzymes with colossal interest, such as aspartic pepsin, serine proteases,
trypsin, chymotrypsin, collagenase, etc. Due to the prevailing environmental conditions, marine enzymes can effectively operate at low temperatures, below 4°C, and
within neutral to alkaline pH values. Enzymatic methods have become an important
and essential part of the processes used by the modern food and feed industry, to
produce a large and diverse range of products for human and animal consumption.
The aquatic environment contains the largest pool of genetic material and hence
has enormous potential for the sourcing of different enzymes (Shahidi and Janak
Kamil 2001). Cuttlefish wastes constitute an important source of proteolytic enzymes, particularly the digestive gland which contains a high number of proteinases (Hatate et al. 2000). Balti et al. (2009) extracted and purified trypsin from
the digestive gland of cuttlefish. A cysteine proteinase was partially purified from
the jumbo squid digestive gland (Cárdenas-López and Haard 2009). Hameed and
Haard (1985) recovered cathepsin C from the Atlantic short-finned squid digestive
gland. Some authors suggested that the salt-tolerant and exopeptidase activity of
this enzyme contributes to the pleasant flavour of fermented fish products (Shahidi
and Janak Kamil 2001).
8.2.8 Fish Sauce
Some of the potential uses of squid digestive gland proteinases are towards the preparation of fish sauce. The possibility of utilizing squid-processing by-products for
low-salt fish sauce production has been investigated since the 1980s (Lee et al. 1982;
Raksakulthai et al. 1986). Raksakulthai et al. (1986) showed the high potential of
squid digestive gland, containing proteolytic enzymes, which aid the fermentation
under optimal conditions.
Xu et al. (2008) concluded that squid by-products could be quickly fermented
into low-salt fish sauce with acceptable qualities in terms of aroma and nutrition.
Squid viscera have large and wide variety of uses in processed feeds and food sup-