Fish Scale Gelatin Research Articles

Gelation and thermal characteristics of microwave extracted fish gelatin-natural gum composite gels.

In this study, the gelation and thermal characteristics of microwave extracted fish scale gelatin blended with natural gums such as gum arabic (AG), xanthan gum (XG), guar gum (GG), and tragacanth gum (TG) was evaluated. The nature of interaction and behavior of gelatin in presence of various gums was confirmed by particle size analysis, viscosity profile, FT-IR analysis and turbidity measurements. DSC data revealed that addition of AG, TG and GG remarkably improved the thermal stability of fish gelatin gel. The composite gels of TG, AG, and XG exhibited higher hardness and bloom strength values as compared to pure fish gelatin implying its textural synergy. Based on qualitative descriptive analysis, TG was found to be superior in improving the stability of fish gelatin gel, closely followed by AG. The results suggest that addition of these gums can reduce syneresis and retard melting of gelatin gels at ambient temperature, which are otherwise soft and thermally unstable.

Promotion of foam properties of egg white protein by subcritical water pre-treatment and fish scales gelatin

The aim of this work was to study the effect of fish scales gelatin (FSG) on the foam and interfacial properties of subcritical water (SW) treated egg white protein (EWP) systems. The foam ability of the SW treated EWP (SWEWP) system was obviously better than that of untreated EWP system, although the former had poorer foam stability. The foam ability of the SWEWP system was further enhanced by the addition of FSG by reducing the surface tension. FSG seemed to build an interfacial viscoelastic network at the air − water interface with the increased surface dilational rheological behavior, causing the low drainage of liquid and inhibiting the bubbles coalescence of complex systems. Moreover, variations of surface elasticity matched the foam stability as the FSG concentration increased. This study described the effect of the biopolymer mixing ratio on the foam properties of SWEWP and FSG. This study also offered the possibility to design the production of protein powder with an outstanding capacity for foams formation and stabilization.

Pectin and enzyme complex modified fish scales gelatin: Rheological behavior, gel properties and nanostructure

The rheological behavior, gel properties and nanostructure of complex modified fish scales gelatin (FSG) by pectin and microbial transglutaminase (MTGase) were investigated. The findings suggested that MTGase and pectin have positive effect on the gelation point, melting point, apparent viscosity and gel properties of FSG. The highest values of gel strength and melting temperature could be observed at 0.8% (w/v) pectin. Nevertheless, at highest pectin concentration (1.6% w/v), the gel strength and melting temperature of complex modified gelatin gels decreased. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis revealed that MTGase catalyzed cross-links among soluble fish scales gelatin – pectin complexes, which could be responsible for the observed increase in rheological behavior, gel strength and melting temperature of modified complex gels.

Pre-treatment optimization and properties of gelatin from freshwater fish scales

Enzyme protease A 2G (E.C. 3.4.24.39) was selected to pre-treat grass carp fish ( Ctenopharyngodon idella) scales and response surface methodology (RSM) was adopted for pre-treating optimization. The optimal conditions from RSM were hydrolyze temperature 30.73 °C, amount of protease A 2G 0.22% (w/w) and hydrolyze time 5.52 h, and the resulted gelatin gel strength was 276 ± 12 g. The X-ray spectra indicated that the dried fish scales gelatin had tri-helix structure. The isoionic point (p I) value was about 7.0. The gel strength and gel viscoelastic properties of grass carp fish scale gelatin were higher compared to one commercial porcine skin gelatin 180PS8 at lower temperature, while the imino content (16%), gelling and melting points (20.8, 26.9 °C) were lower. At the same concentration, the α-chain and β-component contents of the gelatin made more contributions to the gel viscoelastic properties under gelling or melting points, while the amino acid composition made more effects to the stability of the gel. The gelling process was monitored by circular dichroism (CD) spectra. The results also showed that fish scales also can be a good source for gelatin.

Comparison of Quantity and Structures of Hydroxyproline-Containing Peptides in Human Blood after Oral Ingestion of Gelatin Hydrolysates from Different Sources

We compared quantity and structures of food-derived gelatin hydrolysates in human blood from three sources of type I collagen in a single blind crossover study. Five healthy male volunteers ingested type I gelatin hydrolysates from fish scale, fish skin, or porcine skin after 12 h of fasting. Amounts of free form Hyp and Hyp-containing peptide were measured over a 24-h period. Hyp-containing peptides comprised approximately 30% of all detected Hyp. The total area under the concentration-time curve of the fish scale group was significantly higher than that of the porcine skin group. Pro-Hyp was a major constituent of Hyp-containing peptides. Ala-Hyp, Leu-Hyp, Ile-Hyp, Phe-Hyp, and Pro-Hyp-Gly were detected only with fish scale or fish skin gelatin hydrolysates. Ala-Hyp-Gly and Ser-Hyp-Gly were detected only with fish scale gelatin hydrolysate. The quantity and structure of Hyp-containing peptides in human blood after oral administration of gelatin hydrolysate depends on the gelatin source.