141
8 Applications, Uses and By-products from Cephalopods
plements because of their nutritional and functional ingredients content. But viscera
contain heavy metals, particularly cadmium, so the application of viscera to food is
limited (Kawasaki et al. 2008). Some research has been reported, for example, the
study of Kawasaki et al. (2008) concerning a purifying treatment for food application, by using microorganisms to remove cadmium from squid viscera. Successful
production of fish sauce from male capelin ( Mallotus villosus) using minced squid
digestive gland was reported, with the highest amount of free amino acids and highest taste preference observed for samples treated with squid digestive gland compared to those treated with the fungal protease, pronase, trypsin and chymotrypsin
(Shahidi and Janak Kamil 2001).
8.2.9 Organic Fertilizer
Cephalopod by-products, because of their high content of proteins, could be considered, through enzymatic hydrolysis, as a good candidate to be an organic fertilizer,
for which there is a growing demand. This could be an interesting development to
support the growth in organic agriculture. Some studies have demonstrated that
fish protein hydrolysate can have an effect beyond the basic nutrition for plants
(Milazzo et al. 1999).
It has been demonstrated that cephalopod waste hydrolysates have potential as
organic fertilizers. Squid hydrolysate fertilizer seems to be similar to synthetic fertilizer, in terms of effectiveness and environmental impacts (Fetter et al. 2009).
Squid hydrolysate fertilizer can improve the growth of the model plant (Peña-Cortés
et al. 2010). Because fertilizer application to lawns can increase nutrient contamination of ground water, NO-N and PO-P have to be quantified. Fetter et al. (2012)
studied the nitrate and phosphate leaching with a squid-based organic fertilizer and
concluded that it does not appear to be more or less environmentally benign than
synthetic fertilizers.
8.2.10 Ink
Cephalopods rely on ejection of dark ink for defence. The ink consists of a suspension of melanin granules and proteoglycans in a viscous and colourless medium.
Cuttlefish ink is a natural substance of marine-product processing. Historically,
Sepia ink has been drawn directly from the ink pouch of the S� officinalis. It is a
dark and semitransparent colour, which can be used as ink for writing or as watercolour. Sepia ink use has been known since the seventeenth century, but it was not
until the nineteenth century that it became really common, especially among photographers, artists and painters (López-Montes et al. 2009). Cuttlefish ink is widely
used in traditional Chinese medicine, due to its antitumour, immunomodulator and
haemostatic effects (Liu et al. 2008). These authors isolated carbohydrates from the
cuttlefish ( S� maindroni) ink, found a novel polysaccharide ‘S� maindroni ink poly-
8 Applications, Uses and By-products from Cephalopods
plements because of their nutritional and functional ingredients content. But viscera
contain heavy metals, particularly cadmium, so the application of viscera to food is
limited (Kawasaki et al. 2008). Some research has been reported, for example, the
study of Kawasaki et al. (2008) concerning a purifying treatment for food application, by using microorganisms to remove cadmium from squid viscera. Successful
production of fish sauce from male capelin ( Mallotus villosus) using minced squid
digestive gland was reported, with the highest amount of free amino acids and highest taste preference observed for samples treated with squid digestive gland compared to those treated with the fungal protease, pronase, trypsin and chymotrypsin
(Shahidi and Janak Kamil 2001).
8.2.9 Organic Fertilizer
Cephalopod by-products, because of their high content of proteins, could be considered, through enzymatic hydrolysis, as a good candidate to be an organic fertilizer,
for which there is a growing demand. This could be an interesting development to
support the growth in organic agriculture. Some studies have demonstrated that
fish protein hydrolysate can have an effect beyond the basic nutrition for plants
(Milazzo et al. 1999).
It has been demonstrated that cephalopod waste hydrolysates have potential as
organic fertilizers. Squid hydrolysate fertilizer seems to be similar to synthetic fertilizer, in terms of effectiveness and environmental impacts (Fetter et al. 2009).
Squid hydrolysate fertilizer can improve the growth of the model plant (Peña-Cortés
et al. 2010). Because fertilizer application to lawns can increase nutrient contamination of ground water, NO-N and PO-P have to be quantified. Fetter et al. (2012)
studied the nitrate and phosphate leaching with a squid-based organic fertilizer and
concluded that it does not appear to be more or less environmentally benign than
synthetic fertilizers.
8.2.10 Ink
Cephalopods rely on ejection of dark ink for defence. The ink consists of a suspension of melanin granules and proteoglycans in a viscous and colourless medium.
Cuttlefish ink is a natural substance of marine-product processing. Historically,
Sepia ink has been drawn directly from the ink pouch of the S� officinalis. It is a
dark and semitransparent colour, which can be used as ink for writing or as watercolour. Sepia ink use has been known since the seventeenth century, but it was not
until the nineteenth century that it became really common, especially among photographers, artists and painters (López-Montes et al. 2009). Cuttlefish ink is widely
used in traditional Chinese medicine, due to its antitumour, immunomodulator and
haemostatic effects (Liu et al. 2008). These authors isolated carbohydrates from the
cuttlefish ( S� maindroni) ink, found a novel polysaccharide ‘S� maindroni ink poly-