The Effect of Castor Oil (Ricinus communis) Concentration on the Physical and Mechanical Characteristics of Tanned Rabbit Fur Skin

This study aims to determine the effect of castor oil concentrations during the oiling step of rabbit fur skin tanning on the physical and mechanical qualities of the final product. The research material consisted of 64 pieces of local rabbit fur skin tanned with castor oil at different concentrations. The experiment was conducted in a completely randomized design (CRD) with 4 treatments (without castor oil/M0, 5% castor oil/M1, 10% castor oil/M2, and 15% castor oil/M3) and 4 replications. To determine its effects towards physical and mechanical qualities, tensile strength (N/cm²), tear strength (N/cm), elongation (%), water absorption (%), suppleness (mm), and thickness (mm) of the tanned fur skin were observed. Castor oil concentration gave a highly significant effect (P<0.01) on tensile strength, tear strength, and water absorption, with values ranging from 622.80 to 1,208.49 N/cm², 74.04 to 159.16 N/cm, and 47.10 to 125.52%, respectively. In contrast, elongation (31.33–44.16%), suppleness (3.08–5.24 mm), and skin thickness (0.76–0.93 mm) were not significantly influenced by the treatment (P>0.05). This study concludes that castor oil can be used as an alternative natural ingredient in the oiling steps of rabbit fur skin tanning process. Moreover, our study demonstrated that 10% castor oil concentration yielded the optimal physical and mechanical properties. Consequently, this formulation is recommended for industrial tanning applications to enhance the valorization of rabbit fur skin.