Design and Experimental Study of a Prototype Device for Low-Temperature Hot Air Generation Using Atmospheric Plasma for Drying and Fungal Decontamination of Thai Herbs
DOI: 10.14416/j.ind.tech.2026.04.011
Keywords:
Atmospheric Discharge Plasma, Low-Temperature Hot Air Drying, Herbal Drying, Microbial Decontamination, Total MoldsAbstract
This study presents the design and experimental evaluation of a prototype system for generating low-temperature hot air integrated with atmospheric-pressure plasma for simultaneous herbal drying and fungal decontamination. The system combines a heat generation module with plasma-induced reactive species and a controlled hot-air circulation mechanism. Experimental results demonstrate that the prototype increased the internal air temperature from 24 °C to 34 °C using a single electrode, with an electrode surface temperature of approximately 53 °C. Drying experiments indicate that the system reduced the moisture content of sliced fingerroot by 16.6% within 40 minutes and sliced ginger by 10.53% within 60 minutes. In terms of antifungal performance, the total mold count on fingerroot surfaces was reduced to 0.8-7.5% of the initial contamination level. These results confirm the capability of the proposed system to simultaneously achieve moisture reduction and microbial decontamination within a single process. The developed prototype is particularly suitable for high-value herbs or seeds requiring low-temperature drying to preserve bioactive compounds while ensuring microbial safety, indicating strong potential for value-added processing in Thai herbal applications.
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