Comparative analysis of electrohydrodynamic, hot air, and natural air drying techniques on quality attributes and umami enhancement in king oyster mushroom (Pleurotus eryngii)

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Abstract

This study systematically examined the impacts of three distinct drying techniques (Electrohydrodynamics, Hot air and Natural air) on the physicochemical characteristics of king oyster mushroom. Comprehensive evaluations were conducted focusing on drying characteristics, textural properties, bioactive compounds, and umami-enhancing components. Experimental data revealed that EHD-treated samples exhibited voltage-dependent enhancement in drying rate and Dₑff, while demonstrating significant improvement in textural parameters. Notably, specimens processed at 27 kV maintained optimal color comparable to fresh samples, accompanied by superior retention of bioactive components: total polysaccharides (90.32 ± 1.65 mg/g), polyphenols (4.99 ± 0.06 mg/g), and umami nucleotides (17.16 ± 0.40 mg/g), improvements of 86.00 %, 54.01 % and 21.31 %, respectively, compared to natural air-drying. Comparative analysis showed Hot air drying (HAD) achieved maximum total amino acid preservation (25.52 ± 0.94 mg/g), whereas EHD demonstrated efficacy in retaining umami-enhancing compounds, yielding the highest equivalent umami concentration (329.06 ± 10.02 g MSG/100 g) through synergistic preservation of glutamic acid, 5′-inosine monophosphate (5′-IMP), and 5′-guanosine monophosphate (5′-GMP). Meanwhile EHD reduces energy consumption by 87.86–91.84 % compared to conventional drying methods. These findings substantiate the technological advantages of electrohydrodynamic processing in fungal matrix dehydration, providing critical data support for optimizing industrial-scale mushroom drying protocols.