Influence of dielectric barrier discharge plasma processing on yellow passion fruit juice: effects on volatile compound composition and aromatic profile

Abstract

Yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deneger) is valued for its nutritional qualities and sensory attributes, which provide a fresh and fruity taste and aroma. This study presents a novel investigation into the effects of dielectric barrier discharge (DBD) plasma on the complex volatile profile of yellow passion fruit juice. The juice was subjected to cold plasma at different frequencies and exposure times, under a constant voltage. Plasma processing induced specific chemical modification in passion fruit juice that has not been previously reported in other plasma-treated juices. A key novel finding was the dehydrogenation of long-chain esters, increasing unsaturated esters. Isomerization, hydrolysis, and methylation were also observed to a lesser extent. These unique reactions were attributed to passion fruit’s distinct composition, which is rich in long-chain esters. Furthermore, the study also reports on the discrepancy found between chemical analysis and human sensory perception. While chemical calculations (OAV) quantified significant changes in specific aroma descriptors, these modifications were not perceived by a trained Gas Chromatography-Olfactometry (GC-O) panel. This result demonstrates that the significant, measurable chemical modulations induced by plasma can be rendered sensorially irrelevant due to the powerful perceptual masking effect of the juice’s dominant fruity esters. The 1000 Hz treatment reduced the waxy aroma of ethyl octanoate, mitigating juice rancidity when processed with its seeds. Therefore, DBD plasma presents a promising non-thermal application for the food industry to selectively modulate volatile profiles and improve the overall sensory quality of complex fruit juices.