Search

Surface browning is a vital phenomenon that adversely reduces the quality of fresh-cut potatoes. Although many anti-browning methods have been explored, it is unclear whether exogenous catalase (CAT) treatment influences the enzymatic browning. Our results showed that 0.05% CAT immersion for 5 min alleviated browning during cold storage (4°C, 8 days), which was accompanied by a higher lightness and lower redness; additionally, lower H2 O2 and O2 ·- contents were found. The activities of CAT, ascorbate peroxidase, and glutathione peroxidase and the scavenging efficiency of 2,2-diphenyl-1-picrylhydrazyl were also increased. Moreover, CAT treatment inhibited the activities of polyphenol oxidase, peroxidase, and phenylalanine ammonia lyase and reduced phenol accumulation. Treatment with 0.1% hydrogen peroxide (H2 O2 ) achieved the opposite results. This is the first report of CAT application reducing fresh-cut potato browning, providing a safe treatment alternative for enzymatic discoloration and preliminarily revealing the underlying mechanism with insight into antioxidant regulation. PRACTICAL APPLICATION: This research is helpful for fresh-cut potato producers because a novel, safe, easy-to-carry out anti-browning solution was proposed. Dipping in 0.05% catalase solution for 5 min revealed color improvement in the quality of fresh-cut potato slices. The mechanism may rely on enhancing antioxidant ability (ascorbate peroxidase, and glutathione peroxidase, and 2,2-diphenyl-1-picrylhydrazyl scavenging), reducing reactive oxygen species (H2 O2 , O2 ·-, malondialdehyde) and controlling enzymatic browning reaction factors (polyphenol oxidase, peroxidase, and phenylalanine ammonia lyase, and phenol accumulation). This method shows promise for better meeting the requirements and demands of consumers for fresh quality products.

Objectives The purpose of this study was to evaluate the antibrowning functions of hawthorn leaf extract on fresh-cut potato and its possible mechanism. Materials and Methods Fresh-cut potatoes were treated with different concentrations (0.01%, 0.05%, and 0.1%) of hawthorn leaf extract and preserved at 4 ℃ for 8 days. The appearance and colour of potato slices were evaluated, along with the content of the phenol, malondialdehyde (MDA), and hydrogen peroxide (H2O2) during cold storage. Meanwhile, the activities of polyphenol oxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL), lipoxygenase (LOX), catalase (CAT), superoxide dismutase (SOD), and the antioxidant capacity were determined. Furthermore, the composition of hawthorn leaf extract was analyzed by high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS). Results The addition of hawthorn leaf extract effectively delayed the browning process. It not only enhanced the CAT activity and antioxidant capacity but also reduced the LOX activity and accumulation of MDA and H2O2. Meanwhile, the activities of PPO, POD, and PAL as well as the content of phenol were controlled. Additionally, 25 phenols, 34 flavonoids, and 5 proanthocyanidins were identified through high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS), including caffeic acid, quercetin and catechol. Conclusion Hawthorn leaf extract significantly alleviated the browning of fresh-cut potato. It could serve as a natural antibrowning alternative by stabilizing the membrane and modulating reactive oxygen species and redox reactions.