Engineering Design and Performance Evaluation of a UV‐C Treatment System for Postharvest Preservation of Goldenberries ( Physalis peruviana L.)

Goldenberry ( Physalis peruviana L.) is a highly valued Andean fruit with increasing commercial demand; however, its high perishability limits postharvest handling and distribution. Ultraviolet‐C (UV‐C) irradiation has emerged as a promising nonthermal technology for microbial control and shelf life extension in fresh produce. However, the lack of engineering‐based design criteria for UV‐C treatment systems limits their effective and scalable application in postharvest processing. This study is aimed at designing and evaluating UV‐C irradiation systems for the postharvest preservation of goldenberries, emphasizing the influence of chamber configuration on treatment performance. Fruits were exposed to UV‐C radiation (6, 8, and 10 min, corresponding to 3.30, 4.17 and 5.15 kJ/m ² , respectively) using wooden and stainless steel chambers and stored at 4°C for 35 days. Microbiological stability (fungal decay and microbiota dynamics) and physicochemical quality attributes (weight loss, soluble solids, titratable acidity, pH, color, and texture) were monitored. Results demonstrated that UV‐C efficacy is strongly dependent on system design. The stainless‐steel chamber, particularly at 5.15 kJ/m ² exposure, significantly reduced fungal infection and delayed visible decay by up to 14 days compared with untreated controls, while preserving key quality parameters. Improved radiation distribution was associated with enhanced treatment uniformity and effectiveness. Based on these findings, two scalable UV‐C system configurations—a mobile disinfection unit and a continuous tunnel system with rotating rollers—were proposed. Additionally, a validation protocol integrating physical dosimetry and biological efficacy was established to ensure consistent germicidal performance. These results highlight the critical role of engineering design in optimizing UV‐C treatments and demonstrate the potential of this technology as a sustainable and scalable postharvest solution for high‐value fruits.