Edible Coatings Research Articles

The Effect of Antimicrobial Extract on The Characteristics of Tomatoes Coated by Edible Coating based on Tapioca Flour

The edible coating is a food coating material inhibitor of transpiration and respiration. Layer is not fully effective in preventing food spoilage. The spoilage process can occur more quickly if fruit with high moisture content has infected. The research aimed to determine optimum concentration of antimicrobial extract in maintaining shelf life and shrinkage of tomatoes, dominant bacteria in fruit spoilage, between Escherichia coli or staphylococcus. Figure out antimicrobial extracts that are effective in preventing microbial growth. Research begins with the extraction process, testing the active compounds in the extract, combining edible coatings and white turmeric and bitter melon extract with concentrations of 0%, 2.5%, 5%, 10%, 20%, 30%, and 100 respectively), tomato fruit coating. The tests included shelf life, weight loss, best antimicrobial extract, and inhibition diameter. The results more concentration of the extract made the shelf life longer to 14 days and reduced shrinkage by 3.53%. Secondary metabolite compounds in the form of saponins, steroids, and triterpenoids. The minimum concentration of 30% bitter melon and white turmeric extract to prevent bacterial activity and the diameter of the inhibition zone in the range of 10-12 mm showed the extract had the moderate ability. The more dominant bacteria in tomato fruit rot is Staphylococcus aureus.

Assessing the potential of chitosan based coatings in modulation of bacteriome on tomato carposphere

Chitosan based edible fruit coatings are being considered today as an unconventional, ecofriendly and safe alternative of postharvest chemical treatments. The mechanism of action of chitosan coatings, like its antifungal nature or forming a barrier for transpiration and respiration, is already known. We intended to study the effect of the chitosan on natural carposphere microbiome, specifically on non-culturalable bacterial communities during storage to explore the prebiotic like nature of the chitosan based coatings. Hence the effect of coatings viz. CS (1% Chitosan), TL (Tulsi or Ocimum sanctum leaf, 1 g L-1 aqueous extract), and CS/TL mixed (2:1, 1% Chitosan and Tulsi leaf extract) was observed on coated tomato fruit. Metagenomic bacteriome analyses revealed that the untreated samples were comparatively rich epiphytic bacterial flora though the core microbiome was conserved in all the samples. Bacterial community in ripened tomato fruit (after 7 d) was mostly dominated by Acetobacter (49%) while on treatment of coatings genera like Lactobacillus, Weissella, Methylovoruse, Bacillus and Pseudomonas increased. These bacteria can act as potential bio agents in carposphere while the probiotic nature of genera as Lactobacillus or Weissella can also help in delaying the ripening of fruit. As this was a pilot study, more such studies are needed on microbial communities associated with fruits, their assembly and dynamics as well as the nature of their contribution to fruit quality and pathogen resistance during fruit ripening and storage.

Effect of Sonication and Edible Coating on Total Phenolic Content, Antioxidant Capacity, and Physical Characteristics of Infrared-Dried Sweet Cherries

This research studied the influence of combined ultrasonic (40 kHz, 150 W, for 3 min) and 0.2% xanthan gum (XG), guar gum (GG), and wild sage seed gum (WG) coating pretreatments on total phenolic content, antioxidant activity, drying time, effective water diffusivity coefficient ( D eff ), rehydration ratio (RR), total color difference ( Δ E ), and surface shrinkage (SS) of infrared-dried sweet cherries. The ultrasonic pretreatment increased the water transfer rate and water diffusivity during infrared drying and decreased the drying time of fresh sweet cherries. The edible coating enhanced the total phenolic content, antioxidant activity, dehydration time, and RR and decreased the D eff , Δ E , and SS values of infrared-dried sweet cherries. The highest value of total phenolic content (3469.7 μg galic acid/g dry) was recorded for pretreated sweet cherry samples by GG. The mean antioxidant activities for uncoated, XG-coated, GG-coated, and WG-coated sweet cherries were 35.64, 59.88, 54.38, and 61.19%, respectively. In this study, the sweet cherry D eff varied from 2.23 × 10 − 9 m2/s (for untreated cherries) to 5.00 × 10 − 9 m2/s (for sonicated and uncoated cherries). The experimental data for the drying curves were fitted to various single-layer equations, and the Page equation using the experimental constants best described the drying rate of sweet cherries. The mean Δ E values for uncoated, XG-coated, GG-coated, and WG-coated sweet cherries were 15.11, 9.91, 8.74, and 10.69, respectively.

Addition of Silver Nanoparticles to Composite Edible Films and Coatings to Enhance Their Antimicrobial Activity and Application to Cherry Preservation.

The aim of this study was to examine the potential enhancement of the antimicrobial activity of edible films, composed of (i) chitosan (CH), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%) and (ii) hydroxypropyl methylcellulose (HPMC), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%), with silver nanoparticle (AgNP) incorporationat levels 5, 10 and 15% v/v. According to the results, the AgNP addition led to very high antimicrobial activity of both films, reducing by more than 96% the microbial growth of the Gram-negative bacterium Escherichia coli (E. coli) in all cases. On the other hand, by adding AgNPs to films, their thickness as well as oxygen and water vapor permeability decreased, while their transparency increased. Furthermore, the contribution of these specific edible films to preserve cherries under cold storage was investigated. All edible coatings resulted in an improvement of the fruit properties under consideration, and especially the color difference, hardness and total microbial load.

Antifungal edible coatings for fruits based on zein and chitosan nanowhiskers.

Fresh produce have a more limited shelf life than processed ones. Their sensory attributes such as appearance and surface texture are important features in consumer perception and liking. The decomposition of fresh produce, which is caused by enzymes, chemical reactions, and microbial infections, often caused by Colletotrichum species, is inevitable. However, it can be slowed down. Several materials have been developed for this purpose, with an emphasis on active coatings using nanomaterials. In this study, the protective effects of a zein coating containing chitosan nanowhiskers (CSW) for the maintenance of fruit quality were investigated using guava (Psidium guajava L.) as a model fruit. CSW were previously characterized, and their antifungal effects against distinct Colletotrichum species (Colletotrichum asianum, Colletotrichum tropicale, Colletotrichum gloeosporioides, and Colletotrichum brevisporum) were proven. Coatings were characterized by thermogravimetric analysis, optical profilometry, and mechanical properties. Total soluble solids, pH, mass loss, and visual inspection of uncoated and coated guava fruits were also verified during 9 days. Results show that CSW length and aspect ratio decreased for longer extraction times. A similar behavior was found for x-ray diffraction in which peak intensity decreases under the same conditions. CSW degradation (ca. 250-400°C) also depends on extraction time in which more crystalline whiskers are the most thermally stable ones. The addition of CSW did not significantly (p<0.05) modify the homogeneity and continuity of coating but prevented microbial growth assuring fruit quality during storage. In summary, coatings protected guava fruits from post-harvest spoilage while preserving quality and extending shelf life. PRACTICAL APPLICATION: Fresh foods such as fruits and vegetables have a more limited shelf life than processed ones.

Applications of Prolamin-Based Edible Coatings in Food Preservation: A Review

Foods are susceptible to deterioration and sour due to external environmental influences during production and storage. Coating can form a layer of physical barrier on the surface of foods to achieve the purpose of food preservation. Because of its good barrier properties and biocompatibility, prolamin-based film has been valued as a new green and environment-friendly material in the application of food preservation. Single prolamin-based film has weaknesses of poor toughness and stability, and it is necessary to select appropriate modification methods to improve the performance of film according to the application requirements. The practical application effect of film is not only affected by the raw materials and the properties of the film itself, but also affected by the selection of preparation methods and processing techniques of film-forming liquid. In this review, the properties and selection of prolamins, the forming mechanisms and processes of prolamin-based coatings, the coating techniques, and the modifications of prolamin-based coatings were systematically introduced from the perspective of food coating applications. Moreover, the defects and deficiencies in the research and development of prolamin-based coatings were also reviewed in order to provide a reference for the follow-up research on the application of prolamin-based coatings in food preservation.

Films properties of QPM corn starch with Delonix regia seed galactomannan as an edible coating material

Plant-based polysaccharides are considered a good alternative for obtaining edible films and coatings. In this research the objective was to determine the physicochemical characteristics of corn starch obtained from QPM Sac-Beh (SBCS) and Delonix regia galactomannan (DRG) and use them to produce films. Films were elaborated from 1 %(w/v) film-forming solutions (FFS) with SBCS:DRG 1:0, 1:1, and 0:1 ratio. Some films were prepared with glycerol 0.4 %(w/v) and vanillin 0.1 %(w/v). SBCS and DRG were characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and differential scanning calorimetry. SBCS presented low crystallinity which agrees with a low gelatinization ΔH observed. The SBCS:DRG 1:0 FFS without glycerol did not form films; however, DRG addition allows film formation. It was also found that glycerol addition reduced tensile strength to 10.3 MPa, from 41.3 MPa. The lowest water vapor permeability was found in films with 1:1 SBCS:DRG and 0.1 %(w/v) vanillin. This formulation was used to coat D'Anjou pears. This coating conserved the pears' color for 24 days while the control ones started to get a brown color on day 6. Based on the results obtained, FFS elaborated with 1:1 SBCS:DRG and 0.1 %(w/v) vanillin had potential use as edible film material for coating on climacteric fruits preservation.

Layer by layer application of chitosan and carboxymethyl cellulose coatings delays ripening of mango fruit by suppressing cell wall polysaccharides disassembly

Mango is a climacteric fruit that ripens quickly after harvest due to its climacteric nature. Edible coatings have been reported to delay the ripening of various harvested fruit. The efficacy of the applied edible coatings could be improved by using in combination as a layer-by-layer (LBL) approach. So, the influence of LBL application of chitosan (CH) and carboxymethyl cellulose (CMC) was studied on mangoes during postharvest storage at 15 °C for 20 days. Mangoes were coated with monolayers of CH (1 % w/v) and CMC (1 % w/v) as well as LBL application of CH and CMC and were compared with control. The treatment of mangoes with CH and CMC-based LBL treatment resulted in lower decay percentage and weight loss along with higher total chlorophyll pigments and suppressed total carotenoid accumulation. The LBL application of CH and CMC showed lower activity of chlorophyll degrading such as chlorophyllase (CPS), pheophytinase (Phe), Mg-dechalatase (MGD) and chlorophyll degrading peroxidase (Chl-POD) enzymes as well as reduced changes in b*, a* and L* along with a suppressed increase in ethylene (EP) and CO2 production (CPR) rates having higher antioxidant such as catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) and superoxide dismutase (SOD) enzymes activity. In addition, mangoes coated with LBL treatment of CH and CMC exhibited lower water-soluble pectin (WSP) and higher protopectin (PP) having higher concentrations of chelate soluble (CSP) and sodium carbonate-soluble pectin (SCP). Similarly, LBL-coated mangoes showed significantly higher hemicellulose (HCLS) and cellulose (CLS) contents in contrast with control. It was observed that mangoes coated with CH and CMC-based LBL coating exhibited higher flesh firmness and showed suppressed cellulase (CS), pectin methylesterase (PME), polygalacturonase (PG) and β-galactosidase (β-Gal) enzymes activity. The concentrations of total soluble solids and ripening index were markedly lower and titratable acidity was higher in the LBL-based coating treatment in comparison with control. In conclusion, LBL treatment based on CH and CMC coatings could be used for the delay of ripening and softening of harvested mangoes.

Techno-functional characteristics, and potential applications of edible coatings: A comprehensive review

This review emphasizes the growing technical and functional properties of edible coatings, as well as their numerous prospective applications. Edible coatings were developed using proteins, carbohydrates, lipids, and natural polymers. These ingredients could be altered and blended to create coatings with distinct properties. Food products were coated with edible coatings in a number of ways, including dipping, spraying, brushing, rolling, or twirling the food in the coating material. The application strategy applied is dependent on the distinctive food product and the desired outcome. These coatings are at the cutting-edge of innovation and sustainability, employing organic and biodegradable components to efficiently address major environmental challenges. This study additionally investigates the many technical and practical advantages that these coatings have, such as better barrier qualities, precise release mechanisms, and integration with cutting-edge sensor technologies for continuous quality monitoring. It also emphasizes the wide variety of applications, which vary from increasing product shelf life and decreasing food waste to addressing various nutritional demands and improving food aesthetic appeal. The advancements created in the edible coatings industry highlight their crucial role in redefining accepted paradigms of food packaging, preservation, and consumption by fusing scientific advancement with culinary inventiveness are also been discussed. Innovative materials, bioactive compounds for health benefits, and packaging and coatings with less environmental impact are being researched to produce edible coatings with better functionality and sustainability.

Formulation of extracted soyabean starch based edible coatings by different methods and their impact on shelf life of sapota fruit

Sapota fruits were coated with soyabean starch extracted by two different methods and using three different methods of coating (dipping, spraying, and brushing) to determine their effectiveness starch on edible coating stored under ambient (28 ± 2 °C) and refrigerated (3 ± 1 °C) conditions. The samples based on the above six combinations of starch extraction and method of coating were analyzed for physiochemical changes on fruits at 5-day interval for 25 days. The results revealed that the maximum weight reduction was observed in Ambient Control (AC) and Refrigerated Control (RC) samples as 29.89 % and 17.26 % on the 15th day of storage even though RC sample lasted for 25th day. The value for sugar-acid ratio were found as 28.33 (RDT1), 31.88 (RDT2), 33.40 (RST1), 34.22(RST2), 36.44(RBT1), 36.90 (RBT2), and 51.90(RC) on the 15th day of storage for refrigerated storage and for ambient sample it was found as 12.2, 12.82, 13.08,13.30,13.68 and 13.98, respectively, for ADT1, ADT2, AST1, AST2, ABT1 and ABT2 respectively on the 15th day. The Titratable acidity (TA), Vitamin C, firmness, decay incidence, water activity and colour characteristics exhibited higher values for the sapota fruits treated with soyabean starch as compared to the control samples. The RDT1 sample found better results and enhanced the shelf-life of sapota fruit by 2 weeks in comparison to the control samples (AC&RC) at both storage conditions.

CURRENT TRENDS IN THE APPLICATION OF VACCINIUM MYRTILLUS AND ARONIA MELANOCARPA AS NATURAL PRESERVATIVES IN MEAT AND MEAT PRODUCTS: A REVIEW

"In the contemporary food industry, preservation of meat and meat products remains a paramount concern for ensuring safety, quality, and extended shelf life. Against the backdrop of consumer demand for natural and clean-label food additives, this comprehensive review investigates the current trends in utilizing Vaccinium myrtillus (bilberry) and Aronia melanocarpa (chokeberry) extracts as natural preservatives in meat and meat products. The review begins by elucidating the intrinsic antioxidant and antimicrobial properties of these berry extracts, emphasizing their relevance in the preservation of meat products. Recent research highlights their efficacy in reducing lipid oxidation, extending the shelf life of meat products, and inhibiting microbial proliferation. Furthermore, it explores various application methods, including their incorporation into meat matrices and the development of edible coatings, shedding light on innovative techniques and emerging technologies. The practicality of deploying these natural preservatives in meat processing is substantiated through industrial applications and illustrative case studies. Recognizing the promise of these natural preservatives, the review acknowledges the hurdles faced, including formulation optimization, cost-effectiveness, and consumer perceptions. Overcoming these challenges is crucial for their widespread adoption. The review concludes by summarizing key findings and underscores the pivotal role of Vaccinium myrtillus and Aronia melanocarpa in shaping the landscape of meat preservation while ensuring consumer safety and satisfaction."

Potassium Spraying Preharvest and Nanocoating Postharvest Improve the Quality and Extend the Storage Period for Acid Lime (Citrus aurantifolia Swingle) Fruits.

Citrus fruits are one of the most abundant crops globally in more than 140 countries throughout the world. Acid lime (Citrus aurantifolia swingle) is one of the citrus fruits which popularly has rich nutritional and therapeutic features. The storage period is the important factor that affects the economic and quality properties of this fruit. This study aims to demonstrate the enhancing effect of preharvest spraying with potassium, in addition to the postharvest dipping of fruits in some edible coatings, on the quality and storability of acid lime fruits. Preharvest spraying with organic and mineral forms of potassium, namely, potassium thiosulfate 1.75 g/L (S) and potassium tartrate 2 g/L (T), were carried out at three different times, in May, June, and July. On the other hand, postharvest treatments were carried out via dipping fruits in different types of biopolymers (carboxymethyl cellulose (E2) and gum arabic (E3)) and carboxymethyl cellulose/gum arabic composite (E4) as well as nanocoating formulation based on both biopolymers and doped zinc oxide nanoparticles (ZnONPs) (E1), which were prepared via acid lime peel waste extract. Herein, the physiochemical and morphological characterizations confirmed that the nanocoating was prepared at the nanoscale and doped with green synthesis ZnONPs, with recorded sizes of around 80 and 20 nm, respectively. Preharvest spraying with potassium tartrate enhanced fruit traits (Spraying with potassium tartrate at pre-harvest and nanocoating dipping at post-harvest (TE1), spraying with potassium tartrate at pre-harvest and carboxy methyl cellulose dipping at post-harvest (TE2), spraying with potassium tartrate at pre-harvest and gum arabic dipping at post-harvest (TE3) and spraying with potassium tartrate at pre-harvest and carboxymethyl cellulose/gum arabic composite dipping at post-harvest (TE4)), followed by potassium thiosulfate (spraying with potassium thiosulfate at pre-harvest and nanocoating dipping at post-harvest (SE1), spraying with potassium thiosulfate at pre-harvest and carboxy methyl cellulose dipping at post-harvest (SE2), spraying with potassium thiosulfate at pre-harvest and gum arabic dipping at post-harvest (SE3) and spraying with potassium thiosulfate at pre-harvest and carboxymethyl cellulose/gum arabic dipping at post-harvest (SE4)), compared to control. For postharvest treatments, E1 improved fruit quality, followed by E2, E4, and E3, respectively. The integration between pre- and postharvest treatments showed a clear superiority of TE2, followed by TE4, SE1, and SE2, respectively.

Chemically Modified Starches as Food Additives.

Starch is a renewable and multifunctional polysaccharide biopolymer that is widely used both in the food industry and other areas of the economy. However, due to a number of undesirable properties in technological processes, it is subjected to various modifications. They improve its functional properties and enable the starch to be widely used in various industries. A modified starch is a natural starch that has been treated in a way that changes one or more of its initial physical and/or chemical properties. Chemical modification consists of the introduction of functional groups into starch molecules, which result in specific changes in the physicochemical and functional properties of starch preparations. The bases of chemical modifications of starch are oxidation, esterification or etherification reactions. In terms of functionality, modified preparations include cross-linked and stabilized starches. These starches have the status of allowed food additives, and their use is strictly regulated by relevant laws. Large-scale scientific research is aimed at developing new methods of starch modification, and the use of innovative technological solutions allows for an increasingly wider use of such preparations. This paper characterizes chemically modified starches used as food additives, including the requirements for such preparations and the directions of their practical application. Health-promoting aspects of the use of chemically modified starches concerning resistant starch type RS4, encapsulation of bioactive ingredients, starch fat substitutes, and carriers of microelements are also described. The topic of new trends in the use of chemically modified starches, including the production of biodegradable films, edible coatings, and nanomaterials, is also addressed.

Application of antimicrobial chitosan-Furcellaran-hydrolysate gelatin edible coatings enriched with bioactive peptides in shelf-life extension of pork loin stored at 4 and −20 °C

In this study, the authors investigate the preservative capabilities of edible coatings comprising a blend of chitosan, furcellaran and gelatin hydrolysate enhanced with the bioactive peptides RW4 and LL37. The preservative effects on pork samples stored for 21 days at 4 °C and 6 months at −20 °C were studied, while examining changes in microbiological contamination, pH levels, water activity and sensory attributes. Microbiological analyses reveal the coatings' antimicrobial efficacy against aerobic bacteria, microscopic fungi and yeasts, particularly during the initial storage period, when coated samples exhibit microbial reductions of 0.5–2 log CFU/g compared to the controls. The coatings have no discernible impact on water activity during storage in refrigerated or freezer conditions. Notably, differences in pH development can be observed between the coated and control samples, potentially attributable to the antimicrobial action of the coatings. Sensory analysis allows to highlight the inhibition of deterioration related to sensory attributes through the use of edible coatings. In conclusion, employing bioactive peptide-enriched edible coatings holds promise for extending the shelf-life of perishable foods.

Colorimetric Properties of Bombyx mori Silk Fibroin.

Recent reports highlighted several novel applications for the Bombyx mori silk fibroin (SF), as edible coatings for the preservation of food freshness, smart labels, or packaging materials. This study complements these reports and additionally describes the colorimetric sensing properties of the natural protein that could be explored to enhance the practical value of such applications. Our data show that in response to pH changes, reconstituted SF is able to undergo visible color changes that correlate with the intensity of the stimuli, regardless of its physical format or physical cross-linking state. The intensity of the developed color was proportional to the extent of the protein's hydrolytic degradation. We also found that these pH-driven color changes were reversible and interchangeable, with colorless samples at neutral pH, purple in acidic environments, and yellow under basic conditions. Our mechanistic studies identified tryptophan as being responsible for these colorimetric responses, which could be further intensified by the presence of ionized tyrosine functionalities. In addition, we determined that SF's sensing properties also applied to ultraviolet light exposure. Finally, we showed that the innate sensing capabilities of activated SF can be enhanced via the covalent incorporation of additional tryptophan into the protein. Overall, our results further support the utility of SF for sensing applications.

Effects of Essential Oils and Ultrasonic Treatments on Properties of Edible Coatings and Their Application on Citrus Fruits

AbstractIn present study, the effects of orange peel essential oil and ultrasonic treatment on properties of corn starch based edible coating and films including their effects on the shelf life of citrus (Kinnow) fruits are investigated. The ultrasonic approach and essential oil significantly improves the quality characteristics of edible coating formulations, stability, and rheological behaviour of coating materials by reducing the particle size, including antimicrobial activity. The particle size of the coating materials reduces from 2495 nm (control) to 298.8 nm by ultrasonication treatment with improved stability (−39.251 mV) as well as antimicrobial activity. The tensile strength (720 N) and solubility (32.40%) of the CSEOU edible film are also improved as compared to CSEO and CS edible films. The coating formulation enriched with essential oil and ultrasonic treatment (CSEOU) improves the shelf‐life of Kinnow by retarding weight loss (PLW) and microbial load, as well as maintaining higher acidity (TA), total soluble solids (TSS), and higher antioxidant activity. CSEOU treated samples indicate lowest weight loss (24.57%), pH (3.89) with higher TA (3.999%), firmness (494.229 N), phenolic (26.17 mg 100 g−1), flavonoid (34.11 mg 100 g−1), antioxidant (49.04%), and antimicrobial activity against A. niger, E. coli and S. aureus as compared to other samples.

Antimicrobial and antioxidant properties of chitosan-furcellaran-gelatin hydrolysate coatings enhanced with bioactive peptides

The aim of the study was to investigate the antioxidant and antimicrobial properties of novel, edible biopolymer coatings consisting of chitosan, furcellaran, carp skin gelatin hydrolysate and 8 different bioactive peptides: Lfcin-β, MBP-1, PLGG, LL37, Cys-LL37, melittin, RW4 and nisin. In vitro analyses consisted of evaluating FRAP and ABTS radical scavenging properties as well as effectiveness against various food pathogens. Consequently, the coatings were used to investigate their antimicrobial effect during cold storage of smoked pork ham dipped into the coating solutions with and without the presence of CaCl2. Finally, the 2 most effective coatings were applied onto fresh cold stored pork loins with different doses of the investigated peptides (1.25–10 μg/mL). The biopolymer matrix had high radical scavenging properties (76.94%) and FRAP value (5.41 μmol of Trolox/mL), however, the antioxidant power was reduced when peptides were included. The coatings with peptides inhibited the growth of all tested food pathogens aside from Aspergillus flavus. They successfully inhibited the growth of total viable counts (TVC) with reductions even above 3.5 log cfu/g. The inclusion of CaCl2 provided contradictory results for different groups and it was impossible to confirm its effectiveness. Coatings with RW4 and LL37 were selected as the most promising and proved effective in inhibiting the TVC of fresh pork loin, even at doses of 1.25–2.5 μg/mL. The newly developed coatings exhibit high antioxidant and antimicrobial power and could be used to effectively extend the shelf-life of perishable meat products.

Quality and shelf life of strawberry fruit as affected by edible coating by moringa leaf extract, aloe vera gel, oxalic acid, and ascorbic acid

ABSTRACT In the current study, the most effective concentrations of moringa leaf extract (MLE), aloe vera gel (AV gel), ascorbic acid (1 mM) and oxalic acid (5 mM) were used. Physically mature fruits harvested from a commercial orchard were dipped in aqueous solutions of different edible coatings and kept at ambient conditions (25±2ºC & 55-60% RH) for evaluation of the quality and enzymatic parameters on daily basis till marketability. Current results revealed that 5 mM ascorbic acid treatment resulted in 57% reduced fruit weight loss; while 20% AV gel coating increased firmness by 60% over a 5-day ambient storage period. Application 6% MLE exhibited 50.7% and 49.7% reduced respiration rate and ethylene production respectively. Fruit biochemical quality parameters were also improved with the lowest accumulation of total soluble solids as a result of slow respiration, higher titratable acidity, ascorbic acid contents, carotenoids and anthocyanin contents in all treated fruit. While, total phenolic contents and total antioxidants along with superoxide dismutase, catalase, peroxidase, and anthocyanins were higher in ascorbic acid treated fruits. The activity of poly phenol oxidase enzyme was lowest in fruits treated with 5 mM ascorbic acid solution. Conclusively, the application of different edible coatings was proved to be beneficial as numerous fruit biochemical and antioxidative attributes were improved by ascorbic acid treatment; furthermore, MLE, AV gel and oxalic acid treatments were also helpful in maintaining fruit quality of strawberry fruits over a 5-days ambient storage period.

Fabrication, Functional Properties, and Potential Applications of Mixed Gellan-Polysaccharide Systems: A Review.

Gellan, an anionic heteropolysaccharide synthesized by Sphingomonas elodea, is an excellent gelling agent. However, its poor mechanical strength and high gelling temperature limit its application. Recent studies have reported that combining gellan with other polysaccharides achieves desirable properties for food- and biomaterial-related applications. This review summarizes the fabrication methods, functional properties, and potential applications of gellan-polysaccharide systems. Starch, pectin, xanthan gum, and konjac glucomannan are the most widely used polysaccharides in these composite systems. Heating-cooling and ionic-induced cross-linking approaches have been used in the fabrication of these systems. Composite gels fabricated using gellan and various polysaccharides exhibit different functional properties, possibly because of their distinct molecular interactions. In terms of applications, mixed gellan-polysaccharide systems have been extensively used in texture modification, edible coatings and films, bioactive component delivery, and tissue-engineering applications. Further scientific studies, including structural determinations of mixed systems, optimization of processing methods, and expansion of applications in food-related fields, are needed.

The Potential of Chitosan-Starch Blend Polymers as Edible Coatings for The Preservation of Fruits and Vegetables: A Mini-Review

Fruits and vegetables are essential for human life. Maintaining the quality and safety of fruits and vegetables are critical challenges for the food packaging industry in this decade. Chitosan and starch are most widely used for food packaging as they bring unique properties for packaging applications. Chitosan has good antimicrobial properties but weak water vapor permeability. Meanwhile, starch has a better water vapor barrier but has poor mechanical properties. This paper discusses the application of chitosan and starch blends in the field of films and coatings. Several characteristics, such as mechanical, thermal, antimicrobial properties, solubility, and water vapor permeability, are also discussed. This review also discussed several applications of chitosan-starch-based films and coatings for the preservation of fruits and vegetables.