Applying Cold Atmospheric Plasma to Preserve the Postharvest Qualities of Winter Jujube (Ziziphus jujuba Mill. cv. Dongzao) During Cold Storage

Abstract

Winter jujube (Ziziphus jujuba Mill. cv. Dongzao) is a very popular horticultural fruit worldwide, which contains a high number of bioactive compounds. Nevertheless, jujube is perishable by microbial contamination and has a short shelf life under non-controlled conditions. Cold atmospheric plasma (CAP) presents a great potential for food sterilization, maintain postharvest quality, and prolonged storage time. Herein, this study investigated the potential effect of CAP with different exposure times (0, 5, 10, and 20 min) on the physicochemical and biochemical changes in jujube during 15-day storage at 4°C and 90% relative humidity (RH). The results showed that CAP treatment could obviously delay ripening, but displayed no effects on the speed of weight loss and moisture content. Meanwhile, the total native aerobic bacterial count in each jujube group was restrained during whole storage. However, CAP treatment showed a time-dependent manner to improve gene expression (PAL, 4CL, DFR, ANS, LAR, and ANR) related to phenolic biosynthesis. As compared to other groups, 20-min CAP treatment can keep or increase total phenolic content (TPC), maintain antioxidant activity, and reduce oxidative damage. Furthermore, the hydrogen peroxide (H2O2) and malondialdehyde (MDA) content in jujube during middle storage were visibly reduced by 20-min CAP treatment. All in all, our findings concluded that appropriate CAP exposure time can be a promising candidate for the postharvest preservation of jujube.

Inactivation efficacy and mechanisms of atmospheric cold plasma on Alicyclobacillus acidoterrestris: Insight into the influence of growth temperature on survival

“…The stacked loose ω-alicyclic fatty acids can protect acidophilus from high temperature and low pH conditions by forming a dynamic barrier that restricts lipid diffusion and H + transmembrane diffusion ( 36 ). However, different from the mechanism of high temperature and low acid action, various reactive oxygen species and reactive nitrogen components such as ozone, hydroxyl radicals, and singlet oxygen radicals generated by plasma treatment, which will damage the function of fatty acids, induce lipids, especially the peroxidation of unsaturated fatty acids even destroys the cell membrane and leads to cell lysis and bacterial death ( 25 , 41 ). In addition, the free radicals generated by plasma treatment can also cross the cell membrane and enter the cytoplasm to attack the biological macromolecules such as nucleic acids ( 25 ).…”

“…However, different from the mechanism of high temperature and low acid action, various reactive oxygen species and reactive nitrogen components such as ozone, hydroxyl radicals, and singlet oxygen radicals generated by plasma treatment, which will damage the function of fatty acids, induce lipids, especially the peroxidation of unsaturated fatty acids even destroys the cell membrane and leads to cell lysis and bacterial death ( 25 , 41 ). In addition, the free radicals generated by plasma treatment can also cross the cell membrane and enter the cytoplasm to attack the biological macromolecules such as nucleic acids ( 25 ). In this study, A. acidoterrestris as an acidophilic heat-resistant bacteria, and ω-cyclohexyl C17:0 and ω-cyclopentane C18:0 accounted for more than 80%.…”

The synergistic effect of dielectric barrier discharge plasma and phycocyanin on shelf life of Oncorhynchus mykiss rainbow fillets

“…These analyses were performed in triplicate, and the mean value was recorded for each sample. The calculation of the Malondialdehyde (MDA) content in fillets, determined through Thiobarbituric Acid reactive substances )TBARS(, was conducted using the formula 2 and 3 @@ 24 : …”

Maintaining the quality of postharvest broccoli by inhibiting ethylene accumulation using diacetyl

“…The contents of H 2 O 2 and O 2 – were assayed according to the protocols of Hu et al ( 35 ) and Jin et al ( 36 ).…”