Avaliação da solubilidade e do grau de hidrólise enzimática da carne mecanicamente separada de tilápia do nilo (Oreochromis niloticus)

Abstract

Aquaculture is one of the fastest-growing activities in Brazil, and the state of Paraná leads in Nile Tilapia production. The primary form of consumption is through fillet commercialization, resulting in a significant amount of solid waste generated by the fishing industry after filleting. From this residue, mechanically separated meat (MSM) can be obtained, a protein source suitable for obtaining hydrolysates. The study extracted myofibrillar proteins from Nile Tilapia MSM, obtaining a protein concentrate (PC) containing 65.94 g.100g-1 of proteins, 12.03 g.100g-1 of ash, 13.52 g.100g-1 of moisture, and 7.35 g.100g-1 of lipids, satisfactory values regarding protein content for protein concentrate production. The PC was hydrolyzed using the enzyme papain, following a Rotatable Central Composite Design (RCCD), where the enzyme was tested at three different concentrations (0.5; 0.75; and 1%) and time intervals (1.0; 2.5; and 4.0 hours) to evaluate the variables' influence on the hydrolysis process. The highest degree of hydrolysis (131.47 g.100g-1) was obtained in experiment 4, using 1% enzyme concentration with a 4-hour activity time. Solubility was tested at pH 3, 5, 7, 9, and 12, with the lowest value obtained in experiment 3 (1% papain / 1 hour of activity), at pH 3, with a solubility of 56.55 g.100g-1, while the highest solubility was achieved at pH 12 in experiment 2 (0.5% papain / 4 hours of activity). Evaluating the results concerning the degree of hydrolysis and solubility, it was observed that experiment 4 (1% enzyme and 4 hours of activity) obtained the highest degree of hydrolysis and a protein concentrate solubility above 77 g.100g-1 at all evaluated pH levels.