Search

Packaging affects the physiological processes and maintains the quality and safety of food products, which is a critical element in the storage and sale of fresh-cut fruits and vegetables. Thus, the current study sought to establish optimal packaging for fresh-cut cabbage by assessing the physiological and biochemical reactions, nutritional changes, and microbial contamination of samples packaged with five different packaging films. Results demonstrated that polyvinylidene chloride (PVDC) was most efficient in maintaining colour, anthocyanin and phenolic content, inhibiting polyphenol oxygenase activity, limiting browning, delaying weight loss, and reducing the respiration rate. Moreover, the PVDC samples exhibited the highest activity of free-radical scavenging enzymes (peroxidase, superoxide dismutase, and catalase), providing superior reactive oxygen-species scavenging. Meanwhile, the polyethylene samples had the lowest total plate counts and total coliform counts after 6–12 d of storage. Whereas, the poly (butylene adipate-co-terephthalate)/poly lactic acid group exhibited superior inhibition of yeast and mold. After 12 d of storage, the microbial indices of all samples were within 105 CFU g−1, which was within the safety range for fresh-cut vegetables. Therefore, based on the sensory evaluation, physiological quality, antioxidant activity and microbial safety, PVDC film was identified as the best packaging candidate for fresh-cut red cabbage. • This work illuminates the mechanism of quality change in fresh-cut red cabbage. • Reveal the mechanism of regulating quality and safety by different packaging films. • Polyvinylidene chloride (PVDC) best retained colour and nutrients content. • For all films, microbial growth remained within food safety thresholds. • PVDC is recommended, performing best overall, and meeting safety requirements. [ABSTRACT FROM AUTHOR]

In order to clarify an efficient and convenient method to increase the antioxidant activity in broccoli, this study intended primarily to elucidate the effect of cutting type on the quality parameters, antioxidant substance contents and antioxidant activity of broccoli using different floret diameters of 10 × 10 cm (CS1), 5 × 5 cm (CS2), 2.5 × 2.5 cm (CS3) and shredded florets (CS4). The results showed that chlorophyll, total soluble solid, vitamin C and reduced glutathione contents of fresh‐cut broccoli were decreased obviously during the storage. However, there was a significant influence of cutting type on the enzymatic activities involved in phenolic synthesis and oxidation including phenylalanine ammonia‐lyase, cinnamate 4‐hydroxylase, and polyphenol oxidase, which contributed to increasing phenolic content by 26.8%, 30.9%, 46.0%, and 51.3% in CS1, CS2, CS3 and CS4, respectively, and further enhanced the antioxidant activity by more than 60% in fresh‐cut broccoli. Moreover, the activities of antioxidant‐related enzymes, including superoxide dismutase, peroxidase and catalase, were increased significantly in fresh‐cut broccoli. In conclusion, the cutting types had no significant effect on quality but clearly influenced the antioxidant substances and activities of broccoli; therefore, this study provided an efficient and convenient method to enhance the potential nutritional value of broccoli. [ABSTRACT FROM AUTHOR]

• Cutting style has obvious influence on individual phenols content and antioxidant capacity in wounded broccoli. • Illuminate the critical genes expression involved in phenolics synthesis mechanism in wounded broccoli. • Cell antioxidant capacity of shredded broccoli increased by 86.5%. • Wounding stress might be applied as an effective way to get more antioxidants in industrial and domestic processing. To explore the effect of cutting style on the biosynthesis of phenolic compounds and cellular antioxidant capacity in wounded broccoli subjected to different cutting styles (heads, florets, 1/2 florets and shredded florets), the mechanism of the accumulation of phenolic compounds was investigated at the transcriptional level, and cellular antioxidant capacity was measured using a breast cancer cell MCF-7 culture model. The results indicated that the relative expression of the genes encoding phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase and 4-coumarin coenzyme A ligase, three enzymes involved in phenylpropanoid metabolism, was upregulated and that contributed to the synthesis of individual phenolic compounds, including catechin, hydroxybenzoic acid, chlorogenic acid, caffeic acid, sinapic acid, catechin gallate, rutin, cinnamic acid and quercetin. This research constructes the phenol synthesis pathway in wounded broccoli. Moreover, the relative expression of critical genes including superoxide dismutase, peroxidase, catalase, glutathione peroxidase and glutathione reductase involved in the metabolism of reactive oxygen species (ROS) increased, resulting in enhanced antioxidant capacity in wounded broccoli. Cell antioxidant capacity (CAA) of heads, florets, 1/2 florets and shredded florets increased by 52.7%, 59.2%, 64.8% and 86.5%, respectively, compared to whole broccoli. The enhancement of CAA was greater as the intensity of wounding increased, indicating that enhancement of antioxidant activity occurred at the cellular level. This research helps provide a reliable and persuasive theoretical basis for nutritional value assessment at the cellular level in wounded broccoli. [ABSTRACT FROM AUTHOR]