Extraction and characterisation of gelatine from fringescale sardinella (Sardinella fimbriata) bone

Abstract

Gelatine from bone of Fringescale sardinella (Sardinella fimbriata) was extracted and the physico-chemical properties were characterised. The gelatines were extracted at 3% of HCl for 15 hours of pre-treatment time and in hot water extraction at 67°C for 5 hours. Results demonstrated that the yield of gelatines from S. fimbriata was 4.57%. The results also emphasised that S. fimbriata gelatine possessed higher protein content (68.00±7.08), imino acid (proline and hydroxyproline) (109.22glmL, 89.18glmL) and gel strength (178.74±9.51) than those fish species reported in previous studies. However, it was significantly lower than bovine (325.62±32) gelatine. Scanning electron microscopy (SEM) images revealed coarse and looser structures exhibited by S. fimbriata gelatine while finer and compact structures exhibited by bovine. Fourier transform infrared (FTIR) spectroscopy results also elucidated changes in protein secondary structure during collagen to gelatine transformation in both S. fimbriata and bovine gelatines. Overall, findings from this study have suggested that S. fimbriata bone gelatine demonstrated similar physicochemical properties to the bovine, therefore, it can be potentially commercialised to replace the commercial ones.