Lactic and acetic acids are commonly applied as sanitizing agents in meat processing. The incorporation of these acids into hydrogels can be effective because of its ease of production and low cost since they may be easily handled and avoid waste of water after application. The influence of such acids on the hydrogel properties must be precisely known because their presence may affect the microstructure and stability during swelling. The objective of this work was to evaluate swelling properties of enzymatically crosslinked gelatin hydrogels containing lactic and acetic acids. Gelatin hydrogels were synthesized by enzymatic crosslinking with transglutaminase according to the acids concentrations: control (C), containing lactic acid (GRL1 = 12.5 μl mL-1 and GRL6 = 75 μl mL-1), containing acetic acid (GRA1 = 0.78 12.5 μl mL-1 and GRA6 = 4.68 μl mL-1) containing combinations of lactic acid and acetic acid (GRLA1 = 6.25 μl mL-1 lactic acid + 1.25 μl mL-1 acetic acid and GRLA6 = 37.5 μl mL-1 lactic acid + 7.5 μl mL-1 acetic acid). Swelling kinetic was determined by mathematical modeling of water absorption (Higuchi, Kosmeyers-Peppas, Peppas-Sahlin models). The Korsmeyer-Peppas and Peppas-Sahlin models that represent both diffusion and relaxation combined mechanisms fitted the experimental data for all samples. This can be an indicator that the samples swelling ratio is controlled by diffusion and relaxation combined mechanisms. When evaluating Fickian diffusion (FD) and relaxation (R) percent contributions it may be noted that the diffusional process was more important for GRL6 hydrogel during all the swelling kinetic, and for GRLA6 sample the diffusional mechanism was more important in the beginning. The relaxation mechanism presented an important contribution in GRA1 and GRA6 samples. Thus, swelling kinetics modeling indicated the predomination of the diffusion mechanism during water absorption into the dried hydrogel matrix in samples containing lactic acid.