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The uneven maturity and severe internal rot of kiwifruit were rapidly accelerated when transferred to room temperature after long‐term controlled atmosphere storage. In this study, the effects of ethrel combined with different flow microcirculation of antiseptic mediums on the shelf‐life quality of "Qinmei" kiwifruit stored at 20°C were evaluated. Results indicated that the combined aerosolization application of 500 mg/L natamycin, 7.5% w/w H2O2 and 0.5 mg/L atomized ozone could control the decay incidence and respiratory rate of ethrel‐treated kiwifruit. Further studies indicated that ethrel and O3 treatment greatly increased the activities of chitinase, β‐1,3‐glucanase, catalase, and superoxide dismutase and produced higher ascorbic acid levels (151.16 mg·100 g−1/FW) to enhance disease‐resistant of kiwifruit. This treatment could inhibit the activity of polyphenol oxidase and delay the process of membrane lipid peroxidation, contributing to preserving the integrity of cell structures well. Moreover, ethrel + O3 treatment could effectively reduce ethylene production (3.12 μl/kg/h) to delay the ripening and senescence of fruit stored at 20°C. More importantly, this treatment exhibited the lowest contents of decay incidence (9.75%), total bacterial count (4.07 log cfu/g), and yeasts and molds (4.18 log cfu/g), and thus extended the shelf life for up to 16 days. Therefore, a combination of ethrel and ozone is a potentially effective method for the maintenance of the shelf‐life properties of kiwifruit after long‐term cold storage. Novelty impact statement: In this study, the treatment of ethrel‐treated with aerosolized ozone of flow microcirculation of 0.5 mg/L O3 could effectively suppress ripening and senescence, enhance antioxidant capacity and disease resistance, reduce the degree of membrane lipid peroxidation, and considerably preserve the integrity of cell structures, which contributed to preventing the penetration of pathogens, retarding the decay incidence, and delaying the shelf‐life quality deterioration of kiwifruit transferred to room temperature after long‐term controlled atmosphere storage. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of high hydrostatic pressure (HHP) (250 or 400 MPa/5 min) and storage conditions (2 or 27℃/24 hr) on polyphenols, ascorbic acid, antioxidant capacity, polyphenol oxidase (PPO), and color in fresh‐cut cashew apple. The association of HHP and storage decreased ascorbic acid (14%–49%), soluble polyphenols (13%–43%), and antioxidant capacity (41%) and modified phenolic acids profile. Protocatechuic acid was detected in samples after cut and storage. The association of HHP and storage at 27℃ led to hydrolysis of conjugated cinnamic acid, but did not change the flavonoids profile. PPO activity was enhanced after treatment of 250 MPa. Storage at room temperature changed all color parameters and HHP treatment promoted great color differences. Processing at 400 MPa followed by storage at 2℃ seems to be more suitable to fresh‐cut cashew apple since it was less detrimental to ascorbic acid, phenolics, and antioxidant capacity. Practical applications: Cashew apple is a fruit, which is rich in bioactive compounds, ascorbic acid, and polyphenol oxidase, but despite its nutritional content it undergoes fast deterioration, so that HHP could be an alternative to increase its shelf life and consumption. Treatment at 400 MPa and low storage temperature retains ascorbic acid, phenolic compounds, and antioxidant capacity of fresh‐cut cashew apples. The outcomes could help the food industry apply HHP associated with adequate storage temperature to the cashew apple food products to meet the quality standards. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the combined effects of ultrasound (US) and pulsed electric field (PEF) treatment on spinach juice. The spinach juice was sonicated at a frequency of 40 kHz, radiating power 200 W, and temperature 30°C for 21 min in an ultrasonic bath, followed by PEF treatment (pulse frequency: 1 kHz, flow rate: 60 ml/min, temperature: 30°C, time: 335 µs, and electric field strength 9 kV/cm). The combined treatment (US‐PEF) has achieved the highest value of flavonoids, phenolic, flavonols, anthocyanin, carotenoids, total chlorophyll, vitamin C, DPPH, and total antioxidant capacity than single treatments of US and PEF as well as untreated sample. The inactivation of peroxidase and polyphenol oxidase was increased during US‐PEF treatment from 0.85 and 0.025 Abs/min (untreated) to 0.18 and 0.011 Abs/min, respectively. There was a slightly visible variation in color values among all the treatments. Practical applications: Nowadays, novel processing techniques, are employed to improve the nutritional quality and stability of juices. The consequences of the present research showed that combined treatment (US‐PEF) could improve the TPC, TFC, total flavonols, antioxidant activities, chlorophyll, carotenoids, vitamin C, and anthocyanins content while reducing the activity of the enzyme. The verdicts described that US‐PEF can enhance the quality of spinach juice at an industrial scale. [ABSTRACT FROM AUTHOR]

Banana pulps (ripe and overripe) were taken to investigate the effectiveness of various anti‐browning agents (0.1 and 0.2% potassium metabisulfite (KMS), 1 and 2% citric acid (CA), 1% ascorbic acid (AA), 1% CA + 0.5% L‐cysteine, 1% CA + 0.5% CaCl2, 1% CA + 1% AA + 0.5% cysteine) to prevent enzymatic browning. Based on the polyphenol oxidase activity, color and sensory attributes, the most effective anti‐browning agent was selected. Results showed that KMS at 0.1% was most effective in inhibiting the browning reaction, which was further used for evaluating the effect of frozen storage (−16°C) for 180 days along with control. But the control sample lasted for 30 days. In ripe pulp: TSS, total and reducing sugars increased, whereas in overripe it decreased during storage but, the pH remained stable. The ascorbic acid, carotenoids, phenols, and color value decreased for both samples slightly during freeze storage. Practical applications: The response of enzymatic browning in banana pulp to different anti‐browning agents is highly variable. In our findings, we found that potassium metabisulfite (KMS) is highly effective in inhibiting (100%) polyphenol oxidase activity. Further, banana pulp stored with KMS treatments showed a slight variation in physicochemical attributes during frozen storage (−16°C) for 180 days. The banana pulp seems to be an important food industrial application by increasing economic value along with waste reduction by minimize losses during postharvest. However, providing the producer an alternative use for converting pulp into various valuable products. [ABSTRACT FROM AUTHOR]

Sugarcane juice has been associated with a short shelf life due to the rapid enzymatic spoilage and microbial fermentation. The evolution of quality attributes of the high pressure processed (HPP)juice (523 MPa/50°C/11 min) was compared with that of conventionally pasteurizedjuice (90°C/5 min), packed in two different packaging materials, viz., ethylene vinyl alcohol (EVOH) and multi‐layered (ML‐PET) polyethylene terephthalate and stored under refrigerated conditions. The total color difference of the juice samples changed in line with the zero‐order kinetics while the changes in the ascorbic acid, total phenols, antioxidant capacity, and enzyme inactivation were well predicted by the first‐order kinetics. The sensory acceptability of the HPP juice was superior to pasteurized samples. Under refrigeration, the HPP samples in ML‐PET exhibited a shelf life of upto 100 days as against the pasteurized juice, which reported shelf life of 45 days. Practical applications: Commercialization of sugarcane juice is limited by its short shelf life in virtue of rapid microbial fermentation and enzymatic browning. The pasteurization of the sugarcane juice has been found to be effective in preserving the juice and this is often accompanied by loss of heat sensitive nutrients and discoloration due non enzymatic reactions. On this front, the high pressure processing is an alternate technique for preservation of the juice for an extended duration. The technology ensures substantial reduction in the microbial load as well as the spoilage enzymes, ensuring minimal effect on the nutrient profile and sensory attributes. [ABSTRACT FROM AUTHOR]

The impact of pulsed light (PL) treatment conditions on color profile, antioxidant activity, phenolics, vitamin C content, polyphenol oxidase (PPO), and peroxidase (POD) activity in Indian gooseberry (amla) juice was explored. The juice was extracted mechanically from the raw fruits. The intensity of PL varied from 1,504 to 3,012 J·cm−2, and complete inactivation of both PPO and POD was obtained at 2.9 kV for 5 min (3,012 J·cm−2 at 10.04 W·cm−2). The thermal treatment of 95°C/3 min also inactivated PPO and POD completely but resulted in a brownish sample (browning index, BI = 62.73) than PL‐treated (BI = 58.33–60.83) and untreated samples (BI = 58.97). The PL treatment at 2.9 kV for 5 min (3,012 J·cm−2) was the best to produce enzymatically stable amla juice with 45, 54, and 61% more retention in total phenolics, antioxidants, and vitamin C content, respectively than the thermally pasteurized sample. Practical applications: The browning of Indian gooseberry (amla) juice after preparation and during storage is one of the critical issues in the industry. The enzymes such as polyphenol oxidase and peroxidase are responsible for this type of browning and off‐flavor in the juice. Therefore, processing of amla juice while assuring the maximal retention of color and phytochemicals is of great interest. The pulsed light (PL) processing can simultaneously inactivate the enzymes as well as microorganisms while retaining the nutrients in the beverage. The study establishes that PL treatment of 5 min at 2.9 kV (3,012 J·cm−2) can serve as an alternative to conventional batch pasteurization for amla juice when retention of color and bioactive compounds is one of the major concerns. [ABSTRACT FROM AUTHOR]

Nanoemulsion has been shown to extend the postharvest life of horticultural produce. In this study, "Fuji" apple were treated with the combination of nanoemulsion coating‐1 (NC‐1) and 1‐methylcyclopropene (1‐MCP). Biochemical and nutritional values were assessed every 35 days during 280 days storage at 4°C and 90% RH. Results show that apples treated with the combination of NC‐1 and 1‐MCP has significantly reduced mass loss and decay, suppressed malondialdehyde (MDA) content. The combination treatment of NC‐1 and 1‐MCP also retained significantly higher ascorbic acid (ASC), titratable acid (TA), and total soluble solid (TSS) content. NC‐1 and 1‐MCP treatments alone or in combination produced higher peroxidase (POD) and catalase (CAT) activities but lower phenylalanine ammonia‐lyase (PAL) and polyphenol oxidase (PPO) activities than control. Therefore, the combination of NC‐1 and 1‐MCP preserved better "Fuji" apple quality, which could be used to extend the postharvest life of "Fuji" apple during long‐term storage. Practical applications: This research work shows that the combined treatment of NC‐1 and 1‐MCP on "Fuji" apple reduced mass loss, decay and MDA level, retained higher ASC, TA, and TSS content, promoted POD and CAT activities but suppressed PAL and PPO activities, by which preserved better "Fuji" apple qualities during long‐term storage. Moreover, the combination of NC‐1 and 1‐MCP could provide a potential alternative to extend the storage life, which helps in reducing postharvest losses in the supply chain. [ABSTRACT FROM AUTHOR]

This research focused on 1‐methylcyclopropene (1‐MCP) effect during carbon dioxide atmosphere storage on physiology and quality of fresh‐cut Fuji apples. Firmness, color, ascorbic acid, titratable acidity, malondialdehyde (MDA), lipoxygenase (LOX), peroxidase (POD), superoxide dismutase (SOD), polyphenol oxidase (PPO), and catalase (CAT) activities of fresh‐cut Fuji apples were examined. And it turns out under the condition of carbon dioxide storage, 1‐MCP treatment could speed up the decrease of firmness, titratable acidity, and ascorbic acid. Moreover, it enhanced the browning and MDA content of the fruit. Therefore, our results suggested that 1‐MCP + CO2 treatment could enhance carbon dioxide injury as compared with CO2 treatment alone. Furthermore, 1‐MCP + CO2 treatment maintained higher SOD, CAT, POD, PPO, and LOX activities. Overall, 1‐MCP + CO2 treatment enhanced carbon dioxide injury during the storage of high concentration carbon dioxide, possibly through the regulation of LOX activity. Practical applications: The combination of 1‐MCP and CO2 may need to be avoided in fresh‐cut Fuji apple preservation. Moreover, 1‐MCP + CO2 increased antioxidant capacity, including SOD, CAT, PPO, and POD activities, which may provide suggestions for a breakthrough for new preservation methods. [ABSTRACT FROM AUTHOR]

Minimally processed carrots (MPC) was coated with ascorbic acid‐added carboxymethyl cellulose/candelilla wax emulsion, then placed in plastic boxes with perforated polyethylene wrap, and stored at 5°C. It was found that the horizontal cross‐section of samples absorbed larger amounts of emulsion than the lateral surface. The individual wax globules of the coating deposited in the interior of the damaged (by peeling) cortical cells were visualized using scanning electron microscopy. The coating improved water vapor resistance of MPC, temporarily increased the respiratory rate, decreased the activity of polyphenol oxidase, and prevented the formation of "white blush." The acidity, total phenolic content, and texture of the MPC were not affected by the coating treatment. In summary, the edible coating (along with packaging) can serve as a promising approach for maintaining the fresh‐like characteristics of minimally processed carrots through 21 days of cold storage. Practical applications: The treatment of minimally processed carrots with the carboxymethyl cellulose/candelilla wax/ascorbic acid emulsion results in increased moisture retention. Consequently, the coated carrots exhibit reduced weight loss, unchanged hardness, and no "white blush." As expected, the coating inhibited the activity of polyphenol oxidase, most likely due to the MPC surface acidification. In summary, the edible coating (along with packaging) can serve as a promising approach for maintaining the fresh‐like characteristics of minimally processed carrots through 21 days of cold storage. However, the noticeable disadvantage of the coated carrots is the waxy circular deposit around the pericycle and endodermis cells. [ABSTRACT FROM AUTHOR]

ABSTRACT Treatments to inhibit browning of fresh-cut apples were investigated. The color ( L*), the browning potential and polyphenol oxidase (PPO) activity of fresh-cut apples (Golden Delicious, Scarlet Spur and Granny Smith) were evaluated throughout cold storage. Antibrowning agents (citric and ascorbic acid) and calcium chloride resulted in a reduction of browning and deterioration of fresh-cut apples stored at 4C for 5 days under normal atmospheric conditions. During storage, PPO activity increased and was inhibited by the use of citric and ascorbic acids. These antibrowning agents helped to maintaining the color of fresh-cut apples during storage. On the contrary, the use of 1-methylcyclopropene was not effective to prevent the color deterioration of the apple slices from the first day of cold storage. PRACTICAL APPLICATIONS The ready-to-eat fruit and vegetable market has rapidly grown in recent years due to the health benefits associated with these foods because of busy lifestyles, increasing purchasing power and increasingly health-conscious consumers. Nevertheless, because the tissular integrity of fruits is more easily altered during processing, ready-to-use commodities are more perishable than the original materials to browning surface. The use of organic acids such as malic acid, as well as physicochemical quality-stabilizing compounds on fresh-cut fruits and vegetable can benefit the fresh-cut products industry since they can assure the safety and quality of these products. The data collected of this study demonstrated that treatments included 1% w/v of citric acid/CaCl2 and 1% of ascorbic acid/CaCl2 were effective inhibitors of browning surface. For practical purposes the results obtained, we recommend the use of ascorbic acid and citric acid to maintain the quality of fresh-cut apples. [ABSTRACT FROM AUTHOR]

The influence of three chemical dips using ascorbic acid (AA), citric acid (CA) and calcium chloride (CC) on the polyphenoloxidase (PPO) activity and on the total phenolic content of minimally processed (MP) apple (Malus domestica,cv. Jonagored) during cold storage was evaluated and a potential relationship with enzymatic browning was investigated. An ascorbic acid dip (42.6 mM) of 5 min duration was the most efficient chemical treatment in reducing the PPO activity of apple cubes. A 92% inhibition was achieved after 7 days of storage at 4C. All treatments were advantageous in comparison to the control in reducing color changes. Color changes, determined by absorbance at 420 nm (soluble pigments) and lightness (L) (insoluble pigments) of apple cubes treated with ascorbic acid were correlated with total phenolic content. No correlation was observed between PPO activity and tristimulus color parameters, browning index or total phenolic content of AA-treated apple cubes. [ABSTRACT FROM AUTHOR]

Effects of aqueous ozone on winter jujube quality were investigated. Winter jujubes were treated with 1.5, 2, 2.5, and 3 mg/L ozone in water for 5 min. The firmness, color, malonaldehyde (MDA), and other indicators were determined every 20 days. Experimental results showed that 2.5 mg/L aqueous ozone treatment had a positive results on keeping fruit firmness (~23%), titratable acidity (~29%), ascorbic acid (~41%), total soluble solid (~40%), delaying the color change, and the maturation of jujubes compared with nontreated jujubes, and reducing the maximum peak value of polyphenol oxidase activity (~10%) and prolonging the time to reach such a peak value (~40 days). Besides, an obvious reduction in MDA production (~36%) was observed after 100 days. Practical applications: In view of the fact that winter jujubes tend to deteriorate at ambient temperature, a variety of effective methods, including low‐temperature storage, 1‐MCP treatment, modified atmosphere packaging, and coating edible film, have been proposed to achieve the better postharvest quality of fresh jujube. Recently, ozone, as a strong oxidant, has been widely used. In our work, we systematically explored influence of aqueous ozone on winter jujube quality. These results evidence the aqueous ozone treatment is an efficient tactic to improve the edible quality of winter jujube. [ABSTRACT FROM AUTHOR]

Polysaccharides from Osmunda japonica Thunb (Op) exhibit a wide range of biological activities including antibacterial, anti‐inflammatory, antioxidant, and antitumor effects. Carboxymethyl cellulose (CMC) is a type of cellulose derivative that can form dense films. CMC can slow the respiratory transpiration of tomatoes and reduce water evaporation. Coatings of CMC (0.7% concentration) with various levels of Op (0.02%, 0.04%, 0.06%, 0.08%, and 0.1%) were used to preserve tomatoes at room temperature. The treatment, weight loss, hardness, titratable acidity (TA), respiratory intensity, and concentrations of ascorbic acid, polyphenol oxidase, and malondialdehyde (MDA) were evaluated in tomatoes after 0, 5, 10, 15, 20, and 25 days of storage. Compared with untreated tomatoes, the tomatoes with Op‐incorporated CMC coatings had reduced respiratory intensity, weight loss and ascorbic acid loss, increased TA, controlled MDA, and inhibited the decay of tomatoes. Therefore, the use of Op‐incorporated CMC coatings extended the shelf life and maintained the quality of postharvest tomatoes. Practical applications: In the past decades, the use of edible coatings has attracted widespread interest in extending the shelf life of particularly perishable foods. Currently, applications of edible coatings have been proven to be promising as a tool to improve the quality and extend the shelf life of various fruits. But there have been no reports on the effect of Op‐incorporated CMC treatment on the postharvest quality of tomatoes during storage. The purpose of this work is to investigate the efficiency of Op‐incorporated CMC treatment to extend shelf life and provide theoretical guidance for the preservation of tomatoes. [ABSTRACT FROM AUTHOR]

Thermosonication (TS) was applied to optimize the quality characteristics of orange juice and to inactivate Alicyclobacillus acidoterrestris vegetative cells using the Box–Behnken design by varying temperature (45–75°C), time (20–40 min), and frequency (20–60 kHz). Results from the response surface methodology showed that the optimal conditions for TS were 47°C, 30 min, and 20 kHz. The models generated were highly significant (p < .001) with the coefficient of determination of 0.986–0.996. The optimal conditions demonstrated high total phenolic contents (TPC) (490.85 mg GAE/100 ml), pectin methylesterase (PME) enzyme inactivation (94.77%) as well as low A. acidoterrestris vegetative cells' load (1.00 log reduction). In addition, total flavonoids contents (38.50 mg/100 ml ER), ascorbic acid (441.70 mg/ml), color change ΔE (1.85), polyphenol oxidase enzyme (56%), and antioxidant capacity (FRAP, 107.33 g/100 ml AEAC, DPPH, 85.90%) of treated orange juice showed a significant (p < .05) difference compared to the control. Thus, TS significantly enhanced the quality of the natural orange juice. Practical applications: The negative impact of Alicyclobacillus acidoterrestris is a major concern for the food industry. Reducing their amount in food by thermosonication is gaining much attention lately. This kind of green technology represents a quick, efficient, and economical substitute to improve the quality of fruit juices. [ABSTRACT FROM AUTHOR]

In this work, the feasibility of using ohmicsonication (OS) as a new hurdle technology for pasteurization of not‐from‐concentrate (NFC) apple juice was proposed. Optimization of OS conditions (ohmic heating [OH] temperature and sonication time) was done by response surface methodology with polyphenoloxidase (PPO) activity as endpoint evaluation of the NFC apple juice. The effect of OS as well as sonication (S), thermosonication, OH as an alternative to traditional technologies on inactivation of PPO and some quality parameters were studied. The obtained results showed that the highest inactivation of PPO was by OS treatment (98%). The highest bioactive profiles (ascorbic acid, total carotenoids, and total phenolic contents) and color values were obtained with the S and OS compared to other treatments. In addition, the lowest hydroxymethylfurfural and cloud values were with OS. Finally, OS could be applied as an alternative thermal process to produce NFC apple juice. Practical applications: The results of this study showed that the lab scale ohmicsonication (OS) succeeded as an alternative thermal process to produce NFC apple juice. OS process showed less degradation of the bioactive profile and improved inactivation of polyphenoloxidase in comparision to other treatments. Ohmic heating (OH) is already used in many factories. Therefore, we proposed to include an ultrasound probe instead of the existing blenders in the mixing tank before OH line. This would improve the mixing process as well as getting the ultrasound benefits. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate microwave heating (MW) in the processing of camu‐camu juices. A factorial design (22) with repetition at the central point was performed. We evaluated the effect of microwave power (310‐940 W) and processing time (15‐45 s) on physicochemical characteristics, reduction of enzyme activity (POD and PPO), microbiological quality and bioactive compounds content (DPPH, phenolic compound, ascorbic acid, and anthocyanins). Generally, the juices treated by MW presented better results in comparison to the conventional method. There were no significant changes in pH, titratable acidity, total soluble solids, and color parameter in camu‐camu juices in comparison with untreated samples. The ascorbic acid content in the juices increased after the treatment by MW. A significant reduction of degrading microorganisms was observed for the treated juice in relation to the control juice. Microwave heating can be a good alternative for the treatment of Amazonian fruit juices. Practical applications: The global consumer market requires that foods be high in bioactive compounds to improve human health. The Amazon Rainforest is known worldwide for its rich biodiversity, mainly for its wide variety of foods rich in bioactive compounds. The lack of transportation infrastructure and basic sanitation in the region causes the food to present high microbial contamination that can accelerate food degradation, especially its bioactive compounds. The use of microwave heating may be an opportunity to offer a fast, efficient, and low‐cost process for the reduction of microorganisms in fruit juices and pulps. This study is a pioneer in the use of emerging technologies in the conservation of Amazonian fruit juices, allowing a new opportunity for the food industry to offer products with high nutritional value. [ABSTRACT FROM AUTHOR]