Abstract:
To investigate the effect of a low-voltage electrostatic field (LVEF) on the post-harvest color and flavor of sweet corn (
Zea mays L. var. Nongke Nuo 336), samples were subjected to a 1 kV LVEF treatment during storage for 8 days. Changes in color difference, wrinkling rate, sensory score, the activities of antioxidant enzymes—peroxidase (POD), phenylalanine ammonia-lyase (PAL), and polyphenol oxidase (PPO), malondialdehyde (MDA) content, flavonoid content, organic acids, sugars, and volatile organic compounds (VOCs) were monitored throughout storage. The results showed that the variation in color difference was significantly smaller in the LVEF-treated group. POD and PAL activities remained relatively stable and at higher levels, while the increases in MDA content and PPO activity were lower, and the decline in flavonoid content was slower, suggesting that LVEF mitigated oxidative damage to cellular structures. During storage, LVEF treatment enhanced the accumulation of antioxidant-related organic acids such as chlorogenic acid, neochlorogenic acid, and (R)-3-hydroxybutyric acid, while decreasing the levels of sourness-related organic acids such as azelaic acid and trans-/cis-aconitic acid. Moreover, LVEF treatment effectively slowed the reduction in sugar content, promoted the accumulation of desirable VOCs (e.g., methyl acetate,
β-ocimene, and 4-hexen-3-one), and suppressed the formation of undesirable VOCs (e.g., 1-butanol and acetoin) associated with musty, sour, and fermented odors. Overall, LVEF treatment delayed post-harvest color darkening, preserved flavor quality, and effectively extended the shelf life of sweet corn.