Anaerobic digestion (AD) is a key biotechnological process for the valorization of organic residues, as it reduces their pollutant load and generates valuable products such as volatile fatty acids (VFAs). These compounds have industrial applications as precursors for biopolymers, solvents, and biofuels. In this study, the kinetics of VFAs were evaluated using cattle manure (CM) and swine manure (SM), incubated at 37 °C for 18 days. A completely randomized design was applied with ten sampling times and three replicates per treatment. VFA quantification was performed by HPLC, and parameters such as chemical oxygen demand (COD), pH, and nutrient concentrations (N, P, K) were also analyzed. SM reached a maximum production of 1.699 g/L at day 4, whereas CM peaked at 1.817 g/L on day 10. In both substrates, pH exhibited an initial decline, indicating hydrolytic and acidogenic phases, followed by stabilization toward acetogenic and methanogenic stages. Reductions in COD, nitrogen, and phosphorus were also observed, reflecting intense microbial activity. Both manures proved viable, with SM being more efficient at early stages and CM performing better in later phases. These findings provide key information for the design of biorefineries within circular economy frameworks.