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In this study, 2% chitosan (Ch) (w/v) was enriched with 1% Lippia javanica, Syzygium cordatum, and Ximenia caffra extract to form Ch+L, Ch+S, and Ch+X, respectively. The control film was the chitosan (Ch) film without plant extracts. The composite films were assessed for their antifungal ability using the agar diffusion method against economically relevant plant pathogens, Botrytis cinerea, and Penicillium expansum. These chitosan films were further evaluated using an X-ray diffractometer and scanning electron microscope, and their physical and mechanical properties were also assessed. The medicinal plants in the chitosan matrix had the highest inhibition zone (10 mm) against P. expansum, while the chitosan-only films had the lowest inhibition zone (3.3 mm). Notably, Ch+S and Ch+X films had the highest inhibition zone (10 mm) against B. cinerea, while chitosan-only films did not avert the spread of B. cinerea. Ch+L films had the highest film thickness (0.189 mm), density (1.62 g·cm3), swelling degree (48.6%), and water solubility (32.8%). Films with other plant extracts had moderate properties, while chitosan without plant extract had the least film thickness (0.128 mm), density (1.08 g·cm3), swelling degree (31.9%), and water solubility (18.9%). X-ray diffraction images revealed that the chitosan films fused with plant extracts altered the extent of crystallinity of the films because they ranged between 14,710.43 for chitosan-only films and 26,288.31 a.u. for Ch+S films. Enriching the chitosan-based films with the investigated medicinal plant extracts resulted in different favorable properties and could make good candidates for food preservation and packaging if optimized. [ABSTRACT FROM AUTHOR]

In this study, the methylcellulose edible coating additives, namely, salicylic acid (SA) (1–2.5 mM), canola oil (0.05–0.1%) and tween-80 (0.05–0.1%) were optimized using RSM to improve quality management of pomegranate arils. The central composite design was used, and the response variables included mass loss (ML), total soluble solids (TSS), total phenolic content (TPC) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH scavenging activity). The results showed that ML was affected by the quadratic terms of canola oil, tween-80 and SA, whereas TSS was affected by the quadratic terms of canola oil and tween-80. The interaction of SA and canola oil showed a significant effect on TSS and TPC, whereas DPPH scavenging activity was affected by linear terms of SA and canola oil. The optimized conditions for the independent variables were 1.55 mM, 0.079% and 0.079% for SA, canola oil and tween-80, respectively. The predicted responses were consistent with experimental values, indicating the model accuracy and suitability. [ABSTRACT FROM AUTHOR]

A completely randomized design was applied on pomegranate arils for several post-harvest treatments before the packaging in polypropylene boxes for 15 days at (5 ± 1 °C, 95 ± 2% RH): control (untreated), Aloe vera gel (10% or 20%), 10% Aloe vera + rosehip oil (0.25% or 0.50%), 20% Aloe vera + rosehip oil (0.25% or 0.50%), 10% Aloe vera + cinnamon oil (0.25% or 0.50%), and 20% Aloe vera + cinnamon oil (0.25% or 0.50%). Aloe vera in combination with cinnamon oil resulted in an enhanced shelf life (15 d) compared to the uncoated arils (control). The Aloe vera + cinnamon oil coating led to the retention of total phenolics, anthocyanin, ascorbic acid, and antioxidant activity in context to the quality attributes. Moreover, this coating showed minimal change in the color, total soluble solids, titratable acidity, firmness, delayed ethylene production, respiration rate, and physiological weight loss. Also, A. vera + cinnamon oil coatings significantly (p < 0.05) inhibited the total counts of mesophilic aerobics, coliforms, and yeast and mold. Organoleptic attributes, including color, flavor, aroma, texture, and purchase acceptability were higher for the arils that were treated with 10% A. vera + 0.25% cinnamon oil; thus, this highly economical and easily available coating material can be formulated and used commercially to extend the shelf life and enhance the profit of the producers and/or processors. [ABSTRACT FROM AUTHOR]

The present study evaluated the effect of gum arabic (GA) edible coating pretreatment on the quality of dried red raspberries. Red raspberries were independently pretreated with varied concentrations of GA (3, 5, and 10% (w/v) by dipping for 2 min before oven-drying at 60 °C until the moisture content was below 8% (18–24 h). Raspberries dipped in distilled water were used as the control samples. Quality attributes including colour, moisture content, water activity (aw), hardness, hygroscopicity, rehydration capacity, total soluble solids (TSS), titratable acidity (TA), pH, anthocyanin composition, ascorbic acid (AA) content, total phenolic content (TPC), antioxidant activity, peroxidase (POD), and polyphenol oxidase (PPO) enzyme activity were investigated. GA pretreatment of the raspberries improved the aw (lower), hardness (lower), TSS, TSS/TA ratio, BrimA, AA content, and TPC, whilst it significantly (p < 0.05) reduced the colour properties (redness, chroma, hue angle, and total colour differences) and the total anthocyanin content when compared with the control samples. The DPPH radical scavenging activity, POD, and PPO enzymes residual activities were not significantly (p > 0.05) affected by GA pretreatment. Five different types of anthocyanins, including cyanidin dihexoside, cyanidin 3-O-galactoside, cyanidin 3-O-glucosyl-rutinoside, and cyanidin 3-O-rutinoside were identified and quantified with cyanidin dihexoside being the primary anthocyanin, varying from 951.18–1053.70 µg/g DM. GA pretreatment of raspberries between 3 and 5% could result in improved physicochemical, antioxidant properties and minimum loss of anthocyanins. [ABSTRACT FROM AUTHOR]

Restricted postharvest application of synthetic fungicides in maintaining the quality of citrus fruits has led to a search for alternative postharvest treatments. This study evaluated the efficacy of gum arabic (GA) enriched with green synthesized zinc oxide nanoparticles (ZnO-NPs) in maintaining the postharvest quality of mandarin (cv. Kinnow). ZnO-NPs were synthesized using Bidens pilosa leaf extract and incorporated into GA (2% w/v) at 0, 0.25, 0.5, and 1% to form composite coatings: GA, GA C ZnO-NP 0.25%, GA C ZnO-NP 0.5% and GA C ZnO-NP 1%, respectively. Fruit were dipped for 3 min in the respective coatings, with untreated fruit used as control. Fruit were air-dried, packed in commercial cartons, and stored at 5 1 °C and 90 5% relative humidity (RH) for 40 days and observed at 10 days intervals, plus 5 days at 20 5C and 65 5% RH to determine the incidence of physiological disorders. GA C ZnONP showed promise as an alternative postharvest treatment for controlling postharvest physiological disorders associated with 'Kinnow' mandarin. For instance, GA C ZnO-NP 0.5% markedly minimized weight loss (9.2%), electrolyte leakage (43.8%) and chilling injury incidence (5.4%) compared to control (weight loss; 33.3%, electrolyte leakage; 90.3% and chilling injury incidence; 41.5%) at the end of the storage. GA C ZnO-NP 1% significantly alleviated rind pitting, with 13.2% incidence compared to 45.2% rind pitting incidence in the control fruit. This was due to significantly higher phytochemical and antioxidant capacity and reduced antioxidant enzyme degradation in coated fruit than in control. In conclusion, gum arabic coating enriched with ZnO-NPs at concentrations between 0.5 and 1% is recommended as a viable option to maintain the quality of 'Kinnow' mandarin fruit during cold storage. [ABSTRACT FROM AUTHOR]

Different formulations of chitosan (1%, 2%, or 3%) with the incorporation of cinnamon oil (0.25% or 0.50%) were prepared for the preservation of pomegranate aril cv. Bhagwa. Six combinations of chitosan-cinnamon oil formulations along with one control (untreated) were applied to the freshly extracted arils using the dipping application method. All treatments were found to be effective in enhancing the shelf life, improving the postharvest characteristics, and reducing microbial populations on pomegranate arils during a 15-day storage period at 4 ± 1°C. The treated pomegranate arils exhibited excellent resistance to microbial decay, moisture loss, respiration rate, preservation of phenolics, flavonoids, and antioxidants activity, among other characteristics. Chitosan 2% + cinnamon oil 0.25% edible coating has a high potential to enhance the storage life and biochemical properties and reduce the microbial population of arils. This treatment recorded a higher total phenolic content (18%) and antioxidant activity (16%) than the control sample, respectively, at the end of storage. In addition, the treatment also helped to decrease the microbial activity by 45% compared to the control sample. The present investigation proposed an alternative method to prolong the shelf life of pomegranate arils during the 15 days of storage. [ABSTRACT FROM AUTHOR]

Rapid ripening and softening due to cell wall polysaccharide degradation and disassembly pose major challenges in extending fruit storability. This study aimed to examine the efficacy of Opuntia ficus indica mucilage (OFIM) edible coating in minimizing softening in bananas under retail conditions. Mucilage was extracted from freshly harvested prickly pear cladodes and dried into a powder. Phenolic compounds in OFIM powder were quantified using liquid chromatography-mass spectrometry (LC-MS). OFIM concentrations (1, 2 and 3 % (w/v)) were prepared, and their physicochemical properties were examined. The prepared coatings were applied to harvested banana fruit by dipping and stored at room temperature for 12 days. During the experiment, several parameters were measured, including fruit weight loss, total soluble solids (TSS), titratable acidity (TA), peel color, pulp firmness, ethylene production, respiration rate, ion leakage, malondialdehyde (MDA) content, total chlorophyll a nd carotenoids, chlorophyll-degrading enzymes, protopectin content and water-soluble pectin (WSP) and softening-related enzymes in the peel. Results showed that mucilage treatments effectively delayed cell wall and chlorophyll degradation, as well as carotenoid accumulation, thus inhibiting ripening-associated processes compared to control fruit. OFIM-treated fruit exhibited significantly higher firmness, chlorophyll content, and TA, lower TSS content, ethylene production, respiration rate, MDA concentration, ion leakage and protopectin content than uncoated fruit. This suggests that OFIM edible coating has the potential to maintain quality and extend the shelf life of bananas by suppressing softening enzymes during storage. • Efficacy of Opuntia ficus indica mucilage (OFIM) edible coating on bananas was examined. • OFIM treatments delayed cell wall and chlorophyll degradation in bananas. • OFIM coating maintained quality and extended shelf life by suppressing softening enzymes. • Phenolic compounds in OFIM powder were characterized using LC-MS. • 2 % concentration of OFIM coating was found to be the most effective in maintaining banana quality. [ABSTRACT FROM AUTHOR]

This study evaluated the efficacy of chitosan (CH) functionalized with 24-epibrassinolide (EBR) coating in terms of preserving the postharvest quality of late-harvested pomegranate (cv. Wonderful) fruit. Late-harvested pomegranate fruit were immersed for 3 min in different surface treatment solutions—CH 1.5% (w/v), CH + 2 µM EBR, CH + 5 µM EBR, CH + 10 µM EBR and CH + 15 µM EBR—and distilled water was used as a control treatment. The fruit were air-dried and subjected to long storage duration at 5 °C with 85 ± 5 RH for 12 weeks. At 4-week sampling intervals, a batch of fruits was placed at 21 ± 2 °C and 65–70% RH for a further 3 d period to simulate retail conditions before measurements were taken. Fruit physiological responses, physico-chemical properties, phytochemical contents, antioxidant capacity and physiological disorders were monitored during storage. The results showed that the CH-EBR composite edible coatings significantly (p < 0.05) delayed degradative processes due to senescence. The CH-EBR treatments delayed colour, texture and total soluble solids (TSS) degradation and reduced weight loss, respiration, electrolyte leakage and spoilage compared to the control and CH treatment. The treatment effect was more noticeable on fruit treated with CH + 10 µM EBR, which exhibited lower weight loss (18.19%), respiration rate (7.72 mL CO2 kg−1 h−1), electrolyte leakage (27.54%) and decay (12.5%), and maintained higher texture (10.8 N) and TSS (17.67 °Brix) compared to the untreated fruit with respective values of 24.32%, 18.06 mL CO2 kg−1 h−1, 43.15%, 37.5%, 8.32 N and 17.03 °Brix. This was largely attributed to the significantly higher antioxidant content, including the ascorbic acid content, total phenol content, total anthocyanin content and DPPH (radical scavenging activity), of the coated fruit compared to the control fruit. Therefore, CH + 10 µM EBR treatment is recommended as a postharvest management strategy to improve the quality preservation of late-harvested pomegranate fruit during storage. [ABSTRACT FROM AUTHOR]

The polysaccharide based composite biomaterial (coating) used in preserving fruits and vegetables during storage is attracting increased attention as it is biodegradable material that prolongs shelf life. In the present investigation, chitosan–pullulan (50:50) composite edible coating was prepared with pomegranate peel extract (0.02 g/mL) as an active antioxidant agent. The effect of treatment with pomegranate peel extract enriched chitosan–pullulan composite edible coating on the shelf life of mango fruits during 18 days of storage period at room (23 °C) and cold (4 °C) temperature was evaluated. Results of the present study demonstrated that the application of chitosan–pullulan composite edible coating significantly (p ≤  0.05) influences the storage life of mango fruits at both storage temperatures. The chitosan–pullulan composite edible coating reduced the physiological loss in weight (PLW), and maintained total soluble solids (TSS), acidity and pH of coated mango fruits as compared to the control. In addition, fruit sensory quality such as freshness, color, taste and texture were also retained by the treatment. Furthermore, sustained firmness, phenolic content and antioxidant activity confirmed the effectiveness of the pomegranate peel extract enriched chitosan–pullulan composite edible coating on mango fruits. The phenolic, flavonoid and antioxidant activity of coated fruits were retained by pomegranate peel rich edible coating. Therefore, the chitosan–pullulan (50:50) combination with pomegranate peel extract can be used as an alternative preservation method to prolong the shelf life of mango fruits at room and cold storage conditions. However, more in-depth studies are required at farm and transit level without affecting the postharvest quality of mango fruits, providing more revenue for farmers and minimizing postharvest losses. [ABSTRACT FROM AUTHOR]

This study determined the antimicrobial and antioxidant activity of lemongrass (LO), thyme (TO), and oregano (OO) essential oils and ethanolic extracts of pomegranate peel (PPE) and grape pomace (GPE) as candidate ingredients for edible coatings. Antifungal effects against Botrytis cinerea and Penicillium spp. were tested using paper disc and well diffusion methods. Radical scavenging activity (RSA) was evaluated using 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid assays. Gas chromatography-mass spectrometry analysis identified limonene (16.59%), α-citral (27.45%), β-citral (27.43%), thymol (33.31%), paracymene (43.26%), 1,8-cineole (17.53%), and trans-caryphellene (60.84%) as major compounds of the essential oils. From both paper disc and well diffusion methods, LO recorded the widest zone of inhibition against tested microbes (B. cinerea and Penicillium spp.). The minimum inhibitory concentrations of LO against B. cinerea and Penicillium spp., were 15 µL/mL and 30 µL/mL, respectively. The highest (69.95%) and lowest (1.64%) RSA at 1 mg/mL were recorded for PPE and OO. Application of sodium alginate and chitosan-based coatings formulated with LO (15 or 30 µL/mL) completely inhibited spore germination and reduced the decay severity of 'Wonderful' pomegranate. Lemongrass oil proved to be a potential antifungal agent for edible coatings developed to extend shelf life of 'Wonderful' pomegranate. [ABSTRACT FROM AUTHOR]

The effects of edible coatings based on gum arabic (GA) (0.5–1.5%), maize starch (MS) (0.5–1.5%), lemongrass oil (LO) (2–4%), and glycerol (GC) (0.5–1%) developed using response surface methodology (RSM) on "Wonderful" pomegranate fruit were studied. After 42 days of storage (5 ± 1 °C, 95 ± 2% RH) and 5 days at ambient temperature (20 ± 0.2 °C and 60 ± 10% RH), whole fruit were evaluated for weight loss (%) and pomegranate juice (PJ) for total soluble solids (°Brix), titratable acidity (% Citric acid), and antioxidant capacity. The optimization procedure was done using RSM and the response variables were mainly influenced by the concentrations of MS and GA. The optimized coating consisted of GA (0.5%), MS (0.5%), LO (3%), and GC (1.5%) with desirability of 0.614 (0—minimum and 1—maximum). The predicted values of response variables, for the coating were weight loss (%) = 5.51, TSS (°Brix) = 16.45, TA (% Citric acid) = 1.50, and antioxidant capacity (RSA = 58.13 mM AAE/mL PJ and FRAP = 40.03 mM TE/mL PJ). Therefore, the optimized coating formulation is a potential postharvest treatment for "Wonderful" pomegranate to inhibit weight loss and maintain overall quality during storage and shelf-life. [ABSTRACT FROM AUTHOR]

The effect of six edible coatings were investigated on the ability to alleviate shrivel and extend shelf life of plums. Fruit were subjected to a simulated shipping period (−0.5 ± 2 °C and 90 ± 5% relative humidity (RH)) for five weeks and a subsequent shelf life period (20 ± 2 °C and 80 ± 5% RH) for 20 d. Overall, the study showed that it is possible to alleviate shrivel and also extend shelf life of plum ('African Delight™') at export and shelf life conditions. Amongst the edible coatings investigated, the findings in fruit coated with gum arabic and the commercial products were comparable and promising for postharvest preservation of the investigated plum cultivar. The coatings showed a moderate delay of fruit ripening, significantly reduced weight loss and shrivel development, allowing for the export of fruit over a long distance (five weeks) and up to 20 d of shelf life. [ABSTRACT FROM AUTHOR]

• Recent developments on application of edible coatings of stone fruit are discussed. • Addition of lipids to polysaccharide-based coatings increased coating moisture barrier properties. • Stone fruit responded well to the application of edible coatings. • Although there are various edible coatings, research has largely focused on lab-scale trials. • Future research direction should focus on technological readiness level of edible coatings application. Stone fruit, including peaches, nectarines, plums, apricots and cherries, are popular worldwide as a result of their high nutritional value and desirable taste. However, stone fruit are susceptible to various postharvest quality problems including high weight loss, decay, over ripeness and susceptibility to physiological disorders such as internal breakdown and chilling injury symptoms. In the quest to improve fruit storability and shelf life of stone fruit, a lot of research has focused on the postharvest application of edible coatings. However, these coatings have varied effects on the external and internal quality attributes of fruit and the effects are dependent on types of stone fruit. This review, therefore, discusses the different edible coatings applied to enhance storage of stone fruit, with a focus on coating formulation, properties and mode of action specific to stone fruit. Furthermore, gaps in the literature and future prospects of edible coating application on stone fruit are identified. [ABSTRACT FROM AUTHOR]

Much attention and endeavor have been paid to developing biocompatible food packaging films. Here, ethyl cellulose (EC) and polyvinylpyrrolidone (PVP) were fabricated into films through a facile method, microfluidic spinning. Morphology observations showed that the fibers were neatly arranged with an average diameter of 1–4 μm. FTIR and X-ray diffraction analysis suggested the existence of good compatibility and interaction between EC and PVP. Thermogravimetric analysis demonstrated that PVP ameliorates the thermal properties; moreover, the tensile properties were improved, with tensile strength (TS) and Young's modulus up to 11.10 ± 1.04 MPa and 350.16 ± 45.46 MPa, respectively. The optimal formula was EC/PVP (2:3), of which the film displayed an enhanced TS of 4.61 ± 1.15 MPa and a modified water contact angle of 61.8 ± 4.4°, showing fine tensile and hydrophilic performance. This study provides a facile and green film fabrication method promising to be used for food wrapping. [Display omitted] • Ethyl cellulose and polyvinylpyrrolidone were used as the precursors. • Microfluidic spinning was used to produce micro-films with high surface area. • Films of neatly arranged microfibers exhibiting good properties were fabricated. • The films can be potentially used in food packaging applications. [ABSTRACT FROM AUTHOR]