Enhanced Reaction Engineering Approach (REA) for Modeling Continuous and Intermittent Conductive Hydro-Drying of Chili Paste (Capsicum annuum)

The chili pepper (Capsicum annuum) is among the most widely consumed vegetables worldwide, valued for its sensory and nutritional properties. Still, it is highly vulnera-ble to deterioration due to its elevated moisture content. Effective preservation strate-gies, such as the addition of salt combined with drying, are therefore crucial to main-taining quality and extending shelf life. This study employed a modified Reaction En-gineering Approach (REA) to model the drying kinetics and temperature behavior of chili paste under continuous and intermittent conductive hydro-drying conditions. Thirty experiments were conducted, considering various salt concentrations (0, 7.5 y 15 g salt/100 g paste) , water temperatures in the hydro-dryer, and heating intermit-tency through on/off cycles. The modified REA model accurately predicted both mois-ture and temperature profiles, with determination coefficients of 0.9463 and 0.8820, respectively. In addition to direct validation with the complete dataset, cross-validation between cayenne and jalapeño varieties demonstrated the ability of the model to generalize across different formulations and structural characteristics. These results confirm the robustness of the proposed framework and its suitability as a predictive tool for heterogeneous food matrices. Overall, the model provides a reliable platform for analyzing, designing, optimizing, and controlling hydro-drying processes in semi-solid foods, supporting the development of more efficient and sustainable preservation strategies.