352
When a clove added fi lm was applied to the preservation of raw sliced salmon, a
reduction of the growth of total bacteria was observed after 11 days of storage
at 2 °C. This demonstrates that edible fi lms based on fi sh gelatin can be used as an
active packaging applied to fi sh products (Gómez-Estaca et al. 2009b ).
In order to provide gelatin fi lms with antioxidant capacity, two sulphur-free
water-insoluble lignin powders (L1000 and L2400) were blended with a commercial fi sh-skin gelatin from warm water species at a rate of 85 % gelatin: 15 % lignin
(w/w) (G–L1000 and G–L2400), using a mixture of glycerol and sorbitol as plasticizers (Núñez-Flores et al. 2013 ). The gelatin fi lms lose their typical transparent and
colourless appearance by blending with lignin. However, the resulting composite
fi lms gained in light barrier properties, which could be of interest in certain food
applications for preventing ultraviolet-induced lipid oxidation. Lignin proved to be
an effi cient antioxidant at non-cytotoxic concentrations, however, no remarkable
antimicrobial capacity was found.
Additionally, the development of fi sh gelatine-chitosan fi lms modifi ed with
transglutaminase or 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and
plasticized with glycerol has been reported (Kolodziejska et al. 2006 ; Kolodziejska
and Piotrowska 2007 ).
9.2 Shark Skin and Cartilage Gelatin
Shark is caught worldwide. From 1990 to 2003, the reported global catch of sharks
increased by 22 %, 80 % of which was caught by 20 countries including Spain,
France, and the United Kingdom. European Union (EU) countries caught nearly
115,000 metric tons of shark in 2003. Spain took the largest share at around 45 % of
the EU total, followed by France (18 %), the United Kingdom (14 %) and Portugal
(10.5 %) (Lack and Sant 2006 ). Most shark cartilage is utilized for the production of
chondroitin sulphate and calcium. Gelatin can be prepared before and after extraction of chondroitin sulphate and calcium from shark cartilage (Kwak et al. 2009 ).
Shark skin collagen has such features as less imino acid residue content, lower
denaturation temperature, stronger swelling ability, higher solubility in acid
medium, and different fi bril assembly from that of pig skin collagen. Moreover, the
rheological properties of shark collagen solution are also different from those of
land animal origin. As the feature of collagen must refl ect its derivative gelatin, it is
presumed that shark gelatin has also a different characteristic from that of land animals (Yoshimura et al. 2000 ). For example, sol-gel and gel-sol transition temperatures for shark gelatin were remarkably lower than those for pig gelatin (Yoshimura
et al. 2000 ). Shark gelatin gel shows a narrower pH range in which a stable gel is
formed compared with pig gelatin. Melting enthalpy of shark gelatin gel was greater
than that of pig gelatin gel, and G of shark gelatin gel changed more extensively
with rising temperature in comparison with pig gelatin gel. It is concluded that
shark gelatin is different from pig gelatin not only in its gel characteristics, but also
in its solution properties.
9 Marine Gelatins
When a clove added fi lm was applied to the preservation of raw sliced salmon, a
reduction of the growth of total bacteria was observed after 11 days of storage
at 2 °C. This demonstrates that edible fi lms based on fi sh gelatin can be used as an
active packaging applied to fi sh products (Gómez-Estaca et al. 2009b ).
In order to provide gelatin fi lms with antioxidant capacity, two sulphur-free
water-insoluble lignin powders (L1000 and L2400) were blended with a commercial fi sh-skin gelatin from warm water species at a rate of 85 % gelatin: 15 % lignin
(w/w) (G–L1000 and G–L2400), using a mixture of glycerol and sorbitol as plasticizers (Núñez-Flores et al. 2013 ). The gelatin fi lms lose their typical transparent and
colourless appearance by blending with lignin. However, the resulting composite
fi lms gained in light barrier properties, which could be of interest in certain food
applications for preventing ultraviolet-induced lipid oxidation. Lignin proved to be
an effi cient antioxidant at non-cytotoxic concentrations, however, no remarkable
antimicrobial capacity was found.
Additionally, the development of fi sh gelatine-chitosan fi lms modifi ed with
transglutaminase or 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and
plasticized with glycerol has been reported (Kolodziejska et al. 2006 ; Kolodziejska
and Piotrowska 2007 ).
9.2 Shark Skin and Cartilage Gelatin
Shark is caught worldwide. From 1990 to 2003, the reported global catch of sharks
increased by 22 %, 80 % of which was caught by 20 countries including Spain,
France, and the United Kingdom. European Union (EU) countries caught nearly
115,000 metric tons of shark in 2003. Spain took the largest share at around 45 % of
the EU total, followed by France (18 %), the United Kingdom (14 %) and Portugal
(10.5 %) (Lack and Sant 2006 ). Most shark cartilage is utilized for the production of
chondroitin sulphate and calcium. Gelatin can be prepared before and after extraction of chondroitin sulphate and calcium from shark cartilage (Kwak et al. 2009 ).
Shark skin collagen has such features as less imino acid residue content, lower
denaturation temperature, stronger swelling ability, higher solubility in acid
medium, and different fi bril assembly from that of pig skin collagen. Moreover, the
rheological properties of shark collagen solution are also different from those of
land animal origin. As the feature of collagen must refl ect its derivative gelatin, it is
presumed that shark gelatin has also a different characteristic from that of land animals (Yoshimura et al. 2000 ). For example, sol-gel and gel-sol transition temperatures for shark gelatin were remarkably lower than those for pig gelatin (Yoshimura
et al. 2000 ). Shark gelatin gel shows a narrower pH range in which a stable gel is
formed compared with pig gelatin. Melting enthalpy of shark gelatin gel was greater
than that of pig gelatin gel, and G of shark gelatin gel changed more extensively
with rising temperature in comparison with pig gelatin gel. It is concluded that
shark gelatin is different from pig gelatin not only in its gel characteristics, but also
in its solution properties.
9 Marine Gelatins