Inactivation kinetics of peroxidase and polyphenol oxidase in peach juice treated with gaseous ozone

Coriander is vulnerable to a loss in quality during storage. To improve postharvest quality, 0.68 mg/L ozone (O3) was used to treat coriander prior to storage at 20 ± 1°C. Results indicated that O3 maintained the physical appearance of the harvested coriander and suppressed both the respiration rate and polyphenol oxidase activity. O3 treatment inhibited the decline in chlorophyll content and inhibited the activity of the chlorophyll‐degrading enzymes: chlorophyllase, chlorophyll‐degrading peroxidase, Mg‐dechelatase, and pheophytinase. Results also indicated that O3 effectively inhibited the accumulation of hydrogen peroxide and the generation of superoxide anion while increasing the enzyme activity of peroxidase, catalase, and ascorbate peroxidase, compared to untreated coriander. Thus, treatment of coriander with ozone may be a useful approach for maintaining the quality and extending the shelf life of coriander through its regulation of antioxidant and chlorophyll‐degrading enzyme activity. Practical applications Coriander is prone to postharvest yellowing or wilting of its leaves when stored at ambient temperature, and its quality deteriorates due to a rapid increase in senescence. Ozone treatments have been reported to induce disease resistance, stimulate the response to oxidative stress in plants, and effectively delay the decay of fruits and vegetables. Coriander treated with ozone may be a useful approach for maintaining postharvest quality through its regulation of antioxidant and chlorophyll‐degrading enzyme activity. The study demonstrated that ozone is a potential method for suppressing the postharvest quality deterioration in horticultural corps.

Section: Introductionmentioning

confidence: 99%

Effect of ozone on the activity of antioxidant and chlorophyll‐degrading enzymes during postharvest storage of coriander ( Coriandrum sativum L.)

Shi

Jia

et al. 2019

“…Therefore, lots of efforts have been done to find new methods to extract vegetable and fruit bioactive compounds effectively and environmental friendly. Different novel and non‐conventional extraction methods have been studied in recent years (Jaramillo Sánchez, Garcia Loredo, Contigiani, Gómez, & Alzamora, ; Leong, Oey, Clapperton, Aganovic, & Toepfl, ; Liu, Zeng, Cheng, Liu, & Aadil, ; Wang, Zeng, Brennan, Brennan, & Han, ). Such as PEF (Aadil et al, ; Yun, Zeng, Brennan, & Liu, ), high hydrostatic pressure (Wang, Chen, et al, ; Yu et al, ), ultrasounds (Ma et al, ), microwaves (Teh, Niven, Bekhit, Carne, & Birch, ).…”

Section: Introductionmentioning

confidence: 99%

Enhanced extraction of phenolic compounds from onion by pulsed electric field (PEF)

Liu

Zeng

Ngadi

2018

The extraction of water‐soluble phenolic compounds from onion assisted by pulsed electric field treatment (PEF) was investigated as well as the antioxidant activity of the extracts. Results indicated that the yield of water‐soluble phenolic compounds (PC) and flavonoid compounds (FC) from onion was significantly increased after treated by PEF treatment following water extraction. Meanwhile, the antioxidant activity of extracts increased with the increase in electric field intensity and treatment time. Box–Behnken design was employed to optimize the extraction process. The optimal conditions were 2.5 kV/cm, 90 pulses and 45°C for both of PC and FC. Under those conditions, the content of PC and FC in extracts was 102.86 mg GAE 100 g–1 FW and 37.58 mg QE 100 g–1 FW, increased by 2.2 and 2.7 times, respectively, in comparison to control (Non‐PEF treatment) (PC is 32.13 GAE 100 g–1 FW，FC is 10.22 mg QE 100 g–1 FW). Although the extraction yields of PC and FC for PEF‐assisted aqueous extraction was just 1/3 and 1/2 of soxhlet extraction, compared to conventional extraction methods with toxic, organic solvent, PEF‐assisted aqueous extraction method is a selective, environmental friend process to recover water‐soluble PC and FC from onion. Practical application Onion is abundant of phenolic compounds, particularly flavonols which are considered to be a reduced risk of many diseases by inhibition of lipid peroxidation. PEF processing as a non‐thermal technology for preservation of liquid foods has been investigated extensively during the last decades without destroying original sensorial and nutritional properties of food. In this study, it demonstrated that as efficient cell wall disruption technique, the aqueous extraction of phenolic compounds (PC) and flavonoid compounds (FC) from onion was facilitated significantly by PEF treatment. Therefore, PEF‐assisted aqueous extraction method has great potential as a selective, environmental friend process to recover water‐soluble PC and FC from onion.

“…To avoid these problems, several nonthermal technologies are being exploited to guarantee fruit juices safety and retention of quality and nutritional characteristics (Miller, Silva, & Brandão, 2013). Among the nonthermal technologies, ozone is a promising one with potential application to fruits sanitation (Silveira, Oyarzún, & Escalona, 2018) and preservation (Jaramillo Sánchez, Garcia Loredo, Contigiani, Gómez, & Alzamora, 2018;Patil et al, 2010). In 2001, FDA approved ozone application as a direct food additive for the treatment, storage, and processing of foods, due to its classification as "Generally Recognized as Safe" (GRAS status) (Torres et al, 2011).…”

mentioning

confidence: 99%

Impact of ozone processing on microbiological, physicochemical, and bioactive characteristics of refrigerated stored Cantaloupe melon juice

Sroy

Fundo

Miller

et al. 2019

The objective of this study was to evaluate the impact of ozone treatment on microbiological decontamination (intrinsic microflora and inoculated Listeria innocua) and some physicochemical characteristics and bioactive compounds of Cantaloupe melon juice, also during refrigerated storage. To determine adequate ozone exposure, the survival curve of L. innocua was previously assessed. A thermal treatment was also performed seeking comparison with ozone treatment impact. After ozone exposure, L. innocua was not detected in juice samples, while thermal pasteurization allowed a reduction of 5.2 ± 0.2 log cycles. Although ozone reduced the intrinsic microflora loads, this reduction was higher for heat‐treated samples. Vitamin C was highly retained in ozone‐treated juices (68%), when compared with the pasteurized ones (39%). After 13 days of storage, ozone allowed the retention of the most quality parameters analyzed and, therefore, it can be considered as a promising alternative to traditional pasteurization of Cantaloupe melon juice. Practical applications The actual consumers' demand for high‐quality food standards has launched research to alternative and milder nonthermal processes, which have gained increasing attention and importance in the fruit juice industries. Ideally, preservation and/or processing of foods should involve technologies that prevent undesirable microbial survival and minimize quality attributes changes and nutrient losses. Thermal treatments are conventionally used to attain such targets; however, the content and the biological activity of the most health‐related compounds are dramatically reduced. In this context, and particularly in the beverages industries, ozone has been exploited due to its potential for inactivating spoilage and pathogenic microorganisms, while being effective in overall quality retention of the products.