Effects of Extraction Conditions on the Sensory and Instrumental Characteristics of Fish Gelatin Gels

Abstract

Fish skin gelatin has recently been of interest as a product that eliminates religious concerns (Jewish and Muslim) and could be an alternative value-added product from fish waste. Recent research has shown that extraction conditions affect gelatin quality. In this study, gelatin from Asian silver carp skin and extracted under different conditions have been studied sensory properties using descriptive analysis and time intensity testing to determine how extraction conditions affect gelatin sensory properties. Three pairs of gelatin samples were selected based on their gel strength, viscosity, and melting temperature. The impacts of different extraction conditions on instrumental methods were examined. Some functionality measurements were also done to determine how sensory measurements correlate with instrumental measurements. The gel strength varied between 60 ± 10 g and 590 ± 30 g while the viscosity varied between 1.9 ± 0.0 cP and 7.4 ± 0.2 cP. The hardness, melting and gelling temperature of the samples were well correlated with the gel strength (r > 0.90). The results indicated that the strongest correlation among all the sensory attributes was between firmness and melting temperature, which was a negative correlation (-0.75) suggesting that the firmer the gel samples the slower they melt. The viscosity was found to be very discriminative between samples in terms of sensory properties. The functional measurements were found to be strongly correlated within themselves while the sensory measurements were less so, which might be due to the greater variability when using sensory panelists or sensory parameters simply might not be related. The firmness, melting rate, and aftertaste were those sensory attributes most successfully discriminated by the panelists.