“…Fish skins are usually treated with an alkaline solution to remove non-collagenous materials and pigments (Nagarajan et al, 2013;Anand et al, 2013;Nalinanon et al, 2008;Kittiphattanabawon et al, 2010), while a decalcification step has been reported for the extraction of gelatin from fish bones and scales (Sha et al, 2013;Pati et al, 2010, Muyonga et al, 2004aIkoma et al, 2003;Liu et al, 2009;Wang and Regenstein, 2009;Liu et al, 2012). Decalcification has been carried out by acidulation in the case of mackerel (Scomber scombrus) and blue whiting (Micromesistius poutassou) bones (Khiari et al, 2013) and is commonly employed in the production of gelatin from the bones of terrestrial animals (Schreiber and Gareis, 2007); whereas fish scale decalcification has been done using compounds such as ethylenediaminetetraacetic acid (EDTA) (Pati et al, 2010;Nagai et al, 2004;Ikoma et al, 2003;Wang and Regenstein, 2009;Liu et al, 2012), hydrochloric acid (Sha et al, 2013;Wang and Regenstein, 2009), and citric acid (Wang and Regenstein, 2009).…”