β-Galactosidase and lipase were co-immobilized in polymeric blends of gelatin (GEL) and carboxymethyl cellulose (CMC) synthesized with different ratios of GEL/CMC: A (0GEL:100CMC), B (25GEL:75CMC), C (50GEL:50CMC), D (75GEL:25CMC), E (100GEL:0CMC). The films obtained good electrostatic interaction and a regular and uniform structure. The addition of CMC increased the mechanical resistance of the films, the tensile strength being 35.04 ± 0.10 MPa for A (0GEL:100CMC) films and 19.17 ± 2.44 MPa for E (100GEL:0CMC) films. Thermogravimetry (TG) showed that the addition of the enzyme decreases the thermal stability of the films. Film B (25GEL:75CMC) showed greater affinity with the added enzymes and greater thermal stability, in addition to increasing the crystallinity by up to 5.8 % and forming more transparent films. CMC was the most hydrophilic polymer, with higher moisture content (17.35 ± 1.73 %) and PVA (0.398 ± 0.047 g.mm/h.m2.kPa), higher still after the addition of enzyme (22.91 ± 1.06 % and 1.136 ± 0.087 g.mm/h.m2.kPa). The enzymes showed greater interaction with the bulky groups of CMC and the film with the highest concentration of this polymer was the one that presented the best hydrolysis rate of lactose and triglycerides, enabling the production of films.
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