Electromagnetic-Assisted Drying and Decontamination of Mixed Spices

Abstract

This study presents an innovative approach for the finish drying and decontamination of mixed spices. Spices are often susceptible to microbial contamination risks microbial contamination due to poor hygienic conditions during various stages, including harvesting, processing, and storage. Utilizing high-power short-time microwave technology (2.45 GHz), this researchaimed to enhance both the shelf stability and quality attributes of the spices. Samples were exposed to different microwave power densities (10 to 20 W/g). The most effective microbial reduction was observed with a 20 W/g treatment for 60 seconds, followed by six intermittent cycles (10 seconds "ON" and 5 seconds "OFF"). This method resulted in significant reductions of total aerobic mesophilic bacterial counts (2.79 log) and Bacillus cereus (1.83 log). Drying kinetics was studied and Page model provided the best fit, indicating a super-diffusion phenomenon. Furthermore, the 15 W/g treatment notably improved the total phenolic and flavonoid content, as well as the antioxidant capacity, without causing significant alterations in colour. Therefore, this electromagnetic-assisted method offers an effective solution for controlling microbial load and enhancing the chemical characteristics of mixed spices.