Melatonin immersion affects the quality of fresh‐cut broccoli (Brassica oleraceaL.) during cold storage: Focus on the antioxidant system

Abstract

In the current study, fresh‐cut broccoli was soaked in melatonin solution before cold storage (4°C, 95% RH) for 25 days. The results indicated that 100 µM melatonin treatment inhibited the increase of L* and b* values and retained higher hue angle, total chlorophyll content, and fresh weight during storage. Furthermore, 100 µM melatonin treatment obviously increased antioxidant contents including ascorbic acid, total phenols, and flavonoids, and enhanced the antioxidant activity of florets. Individual phenolic compounds including epicatechin, rutin, and quercetin were positively influenced by melatonin treatment. Superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) activities were obviously enhanced by 100 µM melatonin treatment whereas peroxidase (POD) activity was significantly reduced. Moreover, florets treated with melatonin exhibited lower malondialdehyde (MDA), H2O2, and O2− levels. Our research concluded that melatonin treatment could be an effective technique for enhancing antioxidant capacity and improving the quality of fresh‐cut broccoli during cold storage. Practical applications Fresh‐cut fruits and vegetables are more prone to senescence than their intact forms during postharvest storage. Broccoli is a healthy vegetable and has high demands in many countries. In order to reduce economic losses, it is important to delay the senescence and maintain the quality of fresh‐cut broccoli during postharvest storage. In this article, 100 µM melatonin treatment was found to significantly enhance antioxidant capacity and delay the senescence of fresh‐cut broccoli florets, which maintained the quality of broccoli during cold storage. We believe that melatonin treatment can be applied for the preservation of more fresh‐cut fruits and vegetables.

High-Pressure Processing Combined with Microwave Heating: A Potential Approach to Affect the Quality and Enhance Sulforaphane Production in Broccoli Florets

“…Prestamo and Arroyo reported that broccoli exhibited a compact structure and a wet appearance after HPP treatment, and its pressure resistance was better than that of spinach . As we observed, the surface structure of broccoli florets was seriously damaged by 400 MPa treatment (Figure ), which might be beneficial for the extraction of antioxidant components such as ascorbic acid and phenols in broccoli florets and further enhanced the antioxidant capacity . Our results were proof of the arguments mentioned above; 200, 300, and 400 MPa treatments dramatically ( P < 0.05) enhanced the DPPH scavenging ability and ABTS value of florets (Table ), and a similar phenomenon was reported in broccoli hummus subjected to 550 MPa treatment .…”

“…We also recorded the internal temperature of each sample (Figure S6) and found that the internal temperature (65.5 °C) of 400 MPa-treated florets was higher than that of the control after MW heating at 119 W for 10 s (59.7 °C). However, as a thermally degradable component, chlorophyll seemed to degrade after MW treatment in 400 MPa-treated florets, which was often expressed as an increase in b * . The literature reported that chlorophyll in green beans and spinach degraded after HPP treatment at high temperatures, whereas the green color of green beans increased significantly after HPP treatment at room temperature .…”

“…For the determination of DPPH radical scavenging activity, 1 mL of the 50% ethanol extract mentioned above was mixed with 2 mL of a 0.5 mM DPPH ethanolic solution and incubated at room temperature for 30 min, and then the mixture was measured at 517 nm. The DPPH radical scavenging activity was calculated according to our previous study using the formula where A 1 indicates the absorbance of the sample and A 0 indicates the absorbance of the control that was an ethanol solution of DPPH and the absorbance recorded at 517 nm.…”

Effect of Yogurt Serum on Enzymatic and Oxidative Activity in Fresh-Cut Potatoes

“…In one study, it was reported that 100 M melatonin treatment at the end of storage reduced the H 2 O 2 content of cut broccoli by 18% compared to the control. 31 3.4. Effect of YS on Chlorogenic Acid and Total Phenolic Content of Potatoes.…”

“…That was a good percentage. In one study, it was reported that 100 M melatonin treatment at the end of storage reduced the H 2 O 2 content of cut broccoli by 18% compared to the control …”