The influence of a solar‐assisted heat pump dryer integrated with thermal energy storage on reducing fungal load in dried products (maize and groundnuts)

Abstract Background Fungal contamination is a major issue in agriculture, especially during pre‐ and post‐harvest stages, affecting grains like maize and groundnuts. Traditional drying methods, such as open sun drying, have not been effective in preventing fungal risks. This study investigates the thermal performance and the effect of using a solar‐assisted heat pump dryer integrated with thermal energy storage to reduce fungal load in maize and groundnut flour. Results Results showed that the experimental drying process maintained a consistent average temperature of 53°C, showing significant reductions in moisture content ( p < 0.05), supported by drying rates ranging from 0.01 to 0.32. Findings also revealed average coefficients of performance for drying maize and groundnut flour, standing at 3.23 and 3.52, respectively. Furthermore, the results demonstrated good drying efficiency during the drying of maize and groundnut, showing a considerable improvement in overall drying performance. In addition, the solar collector coupled with a thermal energy storage system achieves a remarkable thermal storage efficiency of 71.42% and 71.19%, respectively. Results also revealed a reduction in fungal load in both maize and groundnut flour samples after 8 h of drying, providing compelling evidence of the system's effectiveness in maintaining product safety and quality. The complete elimination of fungal growth was achieved after 32 h. Conclusion Therefore, the proposed drying method has the potential to be a sustainable solution for food processing. This method can improve food safety, extend shelf life, and help reduce food waste, meeting the demand for efficiency in the drying industry.