Freshly cut vegetables are susceptible to microbial contamination and oxidation during handling and storage. Hence, light-emitting diode technology can effectively inhibit microbial growth and improve antioxidant enzyme activity. In this paper, the freshly cut amaranth was treated with different intensities of blue light-emitting diode (LED460nm) over 12 days. Chlorophyll content, ascorbic acid content, antioxidant capacity, antioxidant enzymes activity, the changes in microbial count, and sensorial evaluation were measured to analyze the effects of LED treatment on the amaranth. Blue LED460nm light irradiation improved the vital signs of the samples and extended the shelf life by 2–3 days. The AsA–GSH cycle was effectively activated with the irradiation of 30 μmol/(m2·s) blue LED460nm light. According to the results, the LED460nm light could retard the growth of colonies and the main spoilage bacteria, Pseudomonas aeruginosa, of freshly cut amaranth.

Fresh-cut vegetables are prone to microbiological contamination and oxygenation during handling and storage. In this study, fresh-cut amaranth was subjected to various gas ratios (5–15% O2, 5–15% CO2, 80% N2) for 12 days. Chlorophyll content, ascorbic acid content, antioxidant enzyme activity, microbial population, and physiological and biochemical indicators were measured to evaluate the impact of atmospheric packaging. Suitable atmospheric packaging could slow the respiration of amaranth, delay the decline in physiological and biochemical characteristics, maintain the antioxidant enzyme activity, promote the sensorics, and prolong the shelf life by 2 days. According to the analysis of the results, modified atmospheric packaging (10% O2, 10% CO2, 80% N2) retarded the decline in fresh-cut amaranth quality, provided effective antioxidative browning, and inhibited Pseudomonas fluorescens development.

Fresh sweet corn has a series of physiological and biochemical reactions after picking due to the high moisture content, leading to damaged nutritional value. Rapid freezing of sweet corn after harvest can minimize tissue damage and quality deterioration. In this study, freshly harvested sweet corn was frozen by ultrasound-assisted freezing, brine freezing, strong wind freezing, and refrigerator freezing. The effects of different freezing methods on hardness, water loss, color, epidermal structure, soluble solids content, soluble sugars content, peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activities of frozen sweet corn during storage were investigated. The results showed that brine freezing and strong wind freezing could effectively reduce the quality loss of sweet corn, keep the color, soluble sugars, and soluble solids content of the sweet corn, delay the decrease in antioxidant enzyme activity, and maintain the quality of sweet corn during long term storage.