Effect of wet- and dry-salting with various salt concentrations on pork skin for extraction of gelatin

Gelatin was extracted from pork skin by applying both wet- and dry-salting, and its physical properties were evaluated. The salting-out effect was identified in the dry-salted pork skin groups using 9% and 12% salt. Protein degradation, overall extraction yield, emulsifying activity index, and gel strength of the wet-salted groups tended to increase with increasing saline solution concentration; however, the trend was opposite in the case of dry-salted groups. In contrast, the fat absorption capacity and emulsifying stability index of the gelatin samples showed opposite tendencies. The protein content of gelatin in all salted groups was significantly lower than that of the control group (p < 0.05). The pH of the wet- and dry-salted samples was lower than that of the control sample. The viscosity of gelatin in all salted groups was higher than that of the control group, and the dry-salted groups had higher viscosity than the wet-salted groups, except the wet-salted group with 12% saline solution. Overall, our findings verified that for gelatin extraction from pork skin, both wet- and dry-salting can improve the extraction yield and several physical properties of the gelatin. • Salting-in effect occurred when wet- and dry-salting for extraction of gelatin. • Confirmed that salting-in effect improved gelatin extraction from pork skin. • Physical properties of gelatin were improved when applicated wet- and dry-salting. • Physical properties of gelatin affect negatively when excessive salt addition levels.