Dados do Trabalho

Título

Influence of Glow and Dielectric Barrier Discharge Plasma on the Phenolic Profile of Pineapple (Ananas comosus) juice

Introdução

Cold plasma (CP) offers significant potential for ensuring food quality and safety while preserving heat-sensitive nutrients. Among several industrial applications in recent years, the use of CP to maintain or improve bioactive compounds and antioxidant properties in fruit juices has been extensively investigated. CP induces a wide variety of chemical changes in food components, which can enhance, maintain or reduce nutritional quality, depending on the processing conditions. To better understand its effects on phenolic compounds of juices, it is necessary to investigate these modifications further.

Material e Métodos

In this work, the effect of two cold plasma technologies – glow discharge (GD) and dielectric barrier discharge (DBD) – on the phenolic profile of pineapple (Ananas comosus) juice was investigated and assessed by gas chromatography coupled to mass spectrometry. For DBD treatments, 50 Hz, 500 Hz, and 1000 Hz excitation frequencies were utilized for 20 minutes. For GD treatments, flow rates of 10 mL/min, 20 mL/min, and 30 mL/min were employed for 20 minutes.

Resultados e Discussão

Eleven phenolic compounds were identified in fresh juice, with syringic acid being the major compound, followed by vanillic and ferulic acids. DBD plasma altered slightly the phenolic profile of the samples while GP plasma had the most significant impact on these outcomes. The main changes after DBD treatments were a reduction of vanillic acid and an increase in sinapic, hydroferulic and p-coumaric (50Hz); syringic (500Hz); ferulic, sinapic and hydroferulic acids (1000Hz). Each GD processing condition altered the phenolic profile differently. The flow rate of 30 mL/min notably promotes a significant decrease in vanillic acid levels and a greater increase in hydroferulic and syringic acid levels.

Conclusão

This study showed that higher flow rates of GD plasma had a more intense effect on pineapple juice, promoting the most distinct phenolic profile compared to the untreated juice. The results contributed to advancing our understanding of how plasma processing alters fruit juices.