136
N. Koueta et al.
dyestuffs. They tested cuttlefish ( S� officinalis) bone and squid ( L� vulgaris) pens.
These authors concluded that the deproteinised squid pen had the highest adsorption
capacity but showed an inferior performance to the granular activated carbon tested in
the column experiments (Figueiredo et al. 2005).
8.2.3 Collagen and Gelatine
Collagen is one of the major protein components of connective tissue in multicellular animals. It is also a food constituent and important in developing the texture of
edible tissues and their processed products. A number of studies have demonstrated
that the collagen present in many aquatic animals is an important determinant of the
texture of the processed meats obtained from them. Cephalopods are rich in collagen,
at different concentrations, from 3 to 11 % in the mantle of squid like Illex and Loligo
(Sikorski and Kolodziejska 1986), 18.33 % in the mantle of Dosidicus gigas (TorresArreola et al. 2008). Also, skins are rich in collagen: About 70–80 % of the squid skin
dry matter is collagen (Lin and Li 2012). Two genetically distinct types of collagen
have been identified in the mantle muscle and skin of the common squid T� pacificus
(Mizuta et al. 2009), suggesting that collagens from these species may have relatively
high resistance to hot-water extraction even after their denaturation. This thermal behaviour of squid collagens may contribute to the maintenance of mechanical strength
or structural integration of heat-processed squid meats (Mizuta et al. 2009).
Gelatine is a thermally denatured protein obtained from collagen, generally by
acidic or alkaline processes. Gelatine is a highly nutritious food and low in calories.
Its use in the manufacture of low-fat products or diet products is very common.
Generally, gelatine has a wide range of food, cosmetic, biomedical and pharmaceutical applications, including leather and encapsulation (Balti et al. 2011). Recently,
and especially in the food industry, an increasing number of new applications have
been found for gelatine in products such as emulsifiers (Aewsiri et al. 2011), foaming agents, colloid stabilizers, biodegradable film-forming materials (Hoque et al.
2011b) and microencapsulating agents, in line with the growing trend to replace
synthetic agents with more natural ones. Hoque et al. (2011b) investigated the
properties of blend film based on cuttlefish skin gelatine. During the processing of
cuttlefish, the skin is generated as a by-product with a low market value. To increase
its profitability, cuttlefish skin has recently been used for gelatine extraction (Hoque
et al. 2011a; Aewsiri et al. 2011). However, gelatine yield is low, 2.6 % obtained
from skin of the giant squid D� gigas (Gómez-Guillén et al. 2002). A higher extraction temperature can improve the yield but can negatively affect functional properties. Nagarajan et al. (2012) successfully extracted gelatine from splendid squid
skin at an appropriate temperature. Cuttlefish skin gelatine, modified with tannic
acid, has emulsifying activity and can improve the antioxidative activity. In this
way, it can be used as a natural and safe additive in the food industry (Aewsiri et al.
2010). Balti et al. (2011) improved a gelatine extraction process from cuttlefish skin
by a protease-aided process using smooth hound crude acid protease extract, which
has greater functional properties than bovine skin gelatine, such as foam capacity,
N. Koueta et al.
dyestuffs. They tested cuttlefish ( S� officinalis) bone and squid ( L� vulgaris) pens.
These authors concluded that the deproteinised squid pen had the highest adsorption
capacity but showed an inferior performance to the granular activated carbon tested in
the column experiments (Figueiredo et al. 2005).
8.2.3 Collagen and Gelatine
Collagen is one of the major protein components of connective tissue in multicellular animals. It is also a food constituent and important in developing the texture of
edible tissues and their processed products. A number of studies have demonstrated
that the collagen present in many aquatic animals is an important determinant of the
texture of the processed meats obtained from them. Cephalopods are rich in collagen,
at different concentrations, from 3 to 11 % in the mantle of squid like Illex and Loligo
(Sikorski and Kolodziejska 1986), 18.33 % in the mantle of Dosidicus gigas (TorresArreola et al. 2008). Also, skins are rich in collagen: About 70–80 % of the squid skin
dry matter is collagen (Lin and Li 2012). Two genetically distinct types of collagen
have been identified in the mantle muscle and skin of the common squid T� pacificus
(Mizuta et al. 2009), suggesting that collagens from these species may have relatively
high resistance to hot-water extraction even after their denaturation. This thermal behaviour of squid collagens may contribute to the maintenance of mechanical strength
or structural integration of heat-processed squid meats (Mizuta et al. 2009).
Gelatine is a thermally denatured protein obtained from collagen, generally by
acidic or alkaline processes. Gelatine is a highly nutritious food and low in calories.
Its use in the manufacture of low-fat products or diet products is very common.
Generally, gelatine has a wide range of food, cosmetic, biomedical and pharmaceutical applications, including leather and encapsulation (Balti et al. 2011). Recently,
and especially in the food industry, an increasing number of new applications have
been found for gelatine in products such as emulsifiers (Aewsiri et al. 2011), foaming agents, colloid stabilizers, biodegradable film-forming materials (Hoque et al.
2011b) and microencapsulating agents, in line with the growing trend to replace
synthetic agents with more natural ones. Hoque et al. (2011b) investigated the
properties of blend film based on cuttlefish skin gelatine. During the processing of
cuttlefish, the skin is generated as a by-product with a low market value. To increase
its profitability, cuttlefish skin has recently been used for gelatine extraction (Hoque
et al. 2011a; Aewsiri et al. 2011). However, gelatine yield is low, 2.6 % obtained
from skin of the giant squid D� gigas (Gómez-Guillén et al. 2002). A higher extraction temperature can improve the yield but can negatively affect functional properties. Nagarajan et al. (2012) successfully extracted gelatine from splendid squid
skin at an appropriate temperature. Cuttlefish skin gelatine, modified with tannic
acid, has emulsifying activity and can improve the antioxidative activity. In this
way, it can be used as a natural and safe additive in the food industry (Aewsiri et al.
2010). Balti et al. (2011) improved a gelatine extraction process from cuttlefish skin
by a protease-aided process using smooth hound crude acid protease extract, which
has greater functional properties than bovine skin gelatine, such as foam capacity,