Value added fish by-products - Nordic Innovation

due to the strict EU regulations. There are developments towards a higher focus on the
bioactive properties of the FPH and also an increased refinement of FPH in order to increase
the bioactivity. In this project both different commercial FPH and laboratory prepared FPH
have been evaluated as ingredients in lean and fatty food products.
2.5 Fish gelatin
Gelatin is derived from collagen, which is the principal constituent of connective tissues and
bones. Covalent cross-linking organizes collagen molecules into a three-dimensional structure
while each collagen triple helix is stabilized by hydrogen bonds between three left-handed
helices called α-chains. Gelatin is mainly produced from collagen sources like bovine and
porcine skins, and bovine bones. Although fish gelatin has been extracted from fish skins,
which is a major rest raw material of the fish filleting industry, since 1960, only small
commercial volumes are available (Veis 1964; Balian & Bowes 1977; Ledward 1986;
Norland 1990; Schrieber & Gareis 2007).
However, the outbreak of bovine spongiform encephalopathy (BSE) in Europe during the
1990s has generated a greater focus on gelatin from cold and warm water fish as a possible
alternative to mammalian gelatins. Gelatin has been extracted from several fish species
including cod (Guðmundsson & Hafsteinsson 1997), hake (Montero et al. 1999), megrim
(Montero & Gómez-Guilén 2000), black tilapia and red tilapia (Jamilah & Harvinder 2002),
brown-stripe red snapper and big-eye snapper (Jongjareonrak et al. 2006), Alaska pollock
(Zhou & Regenstein 2005), Atlantic salmon (Arnesen & Gildberg 2007), channel catfish
(Yang et al. 2007), horse mackerel (Badii & Howell 2006) and Nile perch (Muyonga et al.
2004).
Although fish gelatin in contrast to bovine gelatin, is not associated with the risk of Bovine
Spongiform Encephalopathy and contrary to porcine gelatin it is acceptable for Islam,
Judaism and Hinduism, the commercial interest in cold water fish gelatin has been relatively
low due to its suboptimal physical properties. Gelatin from cold water fish species exhibits
lower gel strength, as well as lower gelling and melting temperatures compared to mammalian
gelatin and gelatin from warm water fish species. This is due to a lower content of the imino
acids, proline and hydroxyproline (Piez & Gross 1960; Norland 1990; Leuenberger 1991;
Guðmundsson 2002; Haug et al. 2004).
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