DIFERENTES TIPOS DE ENZIMAS PROTEOLÍTICAS NO PROCESSO DE CURTIMENTO DE PELES DE TILÁPIA DO NILO

During the tanning process the purging step, consists of treating the skins with proteolytic enzymes, aiming at cleaning the fibrous structure. The objective of this study was to evaluate the resistance of Nile tilapia (Oreochromis niloticus) leather, submitted to tanning with the addition of different sources of proteolytic enzymes in the purge stage. Nile tilapia skins were divided into 4 treatments, (1 = no enzyme, 2 = papaya, 3 = pineapple and 4 = Koropon MK ®) and the leathers were submitted to traction and elongation and progressive tear tests. In the tensile test, the leather in which Koropon MK® was used as the enzymatic source presented higher resistance (10.00 N/mm²) and elasticity (86.58%), although it did not differ significantly from those receiving the enzyme pineapple. Further studies should be conducted by increasing the amount of the natural enzymes to improve their action on the fibrous structure, to respond with greater resistance to tear, elasticity and traction. It was concluded that the use of the commercial enzyme Koropon MK® (0.5%) presented better quality.