Plasma activated water on improving the quality of fresh-cut banana slices

Abstract

As a novel technology, plasma activated water (PAW) has been shown to have positive effects on color protection and fruit quality through the modification of the activity of the enzymes. The changes in microstructure, storage properties, flavor compounds, the level of intracellular ROS, and the activity levels of the enzymes involved in browning were comprehensively characterized and determined before and after different PAW (15 s, 30 s, 60 s and 90 s) cold plasma treatments in banana slices. The results suggested that PAW treatments increased intracellular ROS and enhanced the activity of polyphenol oxidase (PPO) in banana slices by 22%, while decreasing the activity of peroxidase (POD) by 21%. Confocal laser scanning microscopy (CLSM) indicated that PAW treatments elevated ROS levels within the sliced cells. Moreover, PAW treatments improved the storage properties of the slices. Further, SEM characterization revealed that the banana slices surface microstructure was affected by the PAW treatment. Additionally, gas chromatograph-mass spectrometry (GC-MS) demonstrated that PAW treatments increased the levels of esters in banana slices (from 64% to 91%), while alcohols were not detected post-treatment. These results indicate that the selection of PAW-30 s treatment has great potential to protect the quality and improve the storability of fresh-cut bananas, which is an economical and eco-friendly way to maintain agricultural products.