NMR evaluation of apple cubes and apple juice composition subjected to two cold plasma technologies

This study evaluated the effects of two cold plasma technologies, glow discharge plasma and dielectric barrier discharge plasma (DBD), on the chemical composition of apple cubes and apple juice analyzed by 1H NMR coupled with chemometrics. The effects of different technologies (glow discharge and DBD) and operating conditions (processing time, gas flowrate, and excitation frequency) were evaluated on the concentration of sugars and organic acids of apple juice and apple cubes. Changes in sugars and organic acids were observed after the application of both plasma technologies. Glow discharge plasma application induced the decrease in sucrose content and the increase in glucose, fructose, and malic acid. Dielectric barrier discharge plasma induced sugar reduction and increased malic acid content. Cold plasma technology depolymerized sucrose into glucose and fructose by cleavage at the ether bond. DBD plasma further induced glucose and fructose consumption, most probably through the phenylpropanoid mechanism. Cold plasma technology could be used to modulate apple products' sensory characteristics, altering both sweetness and sugar-acid ratios.

Automated summary

The study showed that cold plasma technologies could alter the sugar and organic acid content of apple products, with glow discharge plasma leading to a decrease in sucrose and an increase in glucose, fructose, and malic acid, while dielectric barrier discharge plasma resulted in sugar reduction and increased malic acid content.