Fresh apple slice preservation driven by molecular hydrogen.

Here, we observed that surface browning and physiological degradation in fresh-cut apple slices during storage for 8 days (4 °C and 85 % relative humidity) was accompanied by the decreased hydrogen gas (H2) contents. To further investigate whether or how H2 supply influences above processes, H2 modified atmosphere packing (MAP; containing 0.01 %, 0.1 % and 1 % H2) was adopted. Among treatments, 0.1 % H2 MAP not only partially reestablished H2 homeostasis, but also significantly improved fresh apple slice preservation, assessed by retarding browning and water loss. The reduction in quality of fresh cut apple slices, including the sensory quality, nutritional values, and antioxidant capacity, was also slowed down. The non-targeted metabolomics results and molecular evidence revealed that flavonoid biosynthesis originated from the phenylpropane metabolic pathway was remarkably up-regulated in the positive ion mode. Together, our finding suggested that H2 MAP might open a new window for the preservation and processing of fresh-cut produce.