Preliminary Characterization on Physical Properties of Selected Marine Fish Skins as Alternative Sources of Halal Gelatin

Recently, an alternative gelatin from the fish skins in halal market has obtained high demands in many industries. This occurrence has made by - products from the fish such as skins, bones and viscera become valuable and significantly reduced environmental concerns. In this study, there were two types of marine fish u sed; Euthynnus affinis ( Tongkol ) and Decapterus maruadsi ( Selayang ) to extract out gelatin from their skins. The extraction methods were utilized two pre - treatment processes using acidic and alkaline solutions; sulphuric acid, citric acid and sodium hydrox ide to elucidate the quality of obtained gelatin from the different fish skins. There were no significant differences ( p>0.05 ) in their pH, melting point and emulsifying capacity at values of 3.25 ± 0.08 and 3.49 ± 0.04 for pH, 24.0 ± 0.0 ( C) and 23.5 ± 0 .5 ( C) for melting point and 42.59 ± 1.85% and 35.19 ± 1.85% for emulsifying capacity respectively for the E. affinis and D. maruadsi gelatin. Significant differences ( p<0.05 ) were existed in yield, viscosity and emulsifying stability respectively for the E. affinis and D. maruadsi gelatin at values of 6.08 ± 1.29% and 1.56 ± 0.86% for yield, 0.05 ± 0.00 (cP) and 0.03 ± 0.00 (cP) for viscosity and 42.59 ± 1.85% and 33.33 ± 0.00% for emulsifying stability. Throughout the results of gelatin characterization s, E. affinis gelatin had showed better physical properties compared to D. maruadsi gelatin.