Characterization and Development of Gelatin from Cow Bones: Investigation of the Effect of Solvents Used for Soaking Beef Bones

Beef bones contain a gelatin component that can be further extracted. This extraction process requires the right solvent to produce good yield and quality. Gelatin has multifunctional properties, namely biodegradable, biocompatible and non-toxic. This is because it is a natural ingredient that contains high amino acids. The most dominant amino acid content as a parameter for determining the quality of gelatin is proline, glycine, and hydroxyproline. The purpose of this study was to study the effect of the solvent used as a medium for soaking cow bones to be converted into gelatin. The solvent variations used include NaOH, HCl, H2SO4, CH3COOH, and NaHCO2. The concentration variations are 4, 5, 6, 7, 8 (%). This research method includes the preparation of cow bone samples, fat removal, mineral removal, soaking for 7 days, and extraction. The extraction process was carried out with variations times of 4 h and 6 h. The results of the study showed that the highest yield value was with 5% HCl solvent with 4 h extraction time of 26.5% with 8.67% water content, 0.9% ash content, pH 4.64, and viscosity 3.19 cP (p < 0.05). A good isoelectric point is produced when using an acidic solvent, which is between 5.3–5.8. The cross-linking of gelatin with chitosan, glutaraldehyde, and glucose was successfully carried out with the FTIR absorption indicator at a wavelength of 3200 cm−1, which indicates the presence of hydrogen bonds, 1022 cm−1, which indicates the breakdown of aldehyde bonds in glutaraldehyde compounds into C-O bonds. According to the microbial test, when gelatin is combined with chitosan, there will be an increase in the microbial inhibition zone. This shows that the development of gelatin materials is very prospective and promising.