Evaluation of pulsed electric field for the quality maintenance of fresh Hibiscus sabdariffa L. flowers during ambient storage

The quality of Hibiscus sabdariffa L. ( H. sabdariffa L.) flowers is often reduced after harvesting due to high oxidative stress and degradation of nutritional substances and value reduction. This situation shows the need for effective post-harvest methods such as pulsed electric field (PEF) to preserve edible flowers' quality. This study aimed to analyze the effect of PEF at 1, 2, 3, and 4 kV/cm for 2 min on flower quality during ambient storage. Physical characteristics, oxidative stress indicators, antioxidant enzyme activities, and bioactive compound contents were observed during the storage period. Each treatment in this study was carried out with three replications and three repeated measurements. The data were analyzed with two-way ANOVA, and significant differences ( p < 0.05) led to further analysis using the Duncan Multiple Range Test (DMRT) to identify treatment differences. A comparison of the properties was conducted during storage (10 d) between the PEF-pretreated group and the control group. The PEF treatment was able to maintain the quality of H. sabdariffa L. flower in the parameters of relative fresh weight (14–32%), SOD enzyme activity (30–39%), phenolics (11–36%), and anthocyanins up to two-fold higher than the control group. The treatment also suppressed color changes (ΔE) (15–44%), H₂O₂ content (6–23%), and malondialdehyde (14–36%), lower than the control group. This study showed that PEF had potential as a technique for edible flower quality maintenance, including physical quality and bioactive compounds during ambient storage.