Edible Coatings Research Articles

Modern biological methods of processing plant raw materials used to increase its storage capacity

Foodborne illnesses, mainly infectious, are a leading cause of morbidity and mortality worldwide. Pathogenic bacteria are present at virtually every stage of the food production chain, compromising company food safety programs and causing out-breaks of foodborne illnesses in various regions of the world. Finding new solutions that provide adequate microbiological stability to minimally processed foods is key to controlling bacterial pathogens that cause foodborne illnesses. The use of chemical and physical methods of food preservation often leads to a deterioration in their nutritional value, physical and organoleptic properties. Minimally processed foods produced without any radical preservation methods may be at particular risk of developing microorganisms, including pathogens. Low-temperature production processes and refrigerated storage promote the development of psychrophilic microorganisms; another threat is posed by high microbiological contamination of raw materials. To preserve the quality of food products, the most commonly used physicochemical methods include modified atmosphere packaging, membrane methods or ultrasound. Alternatively, biological methods can be used: bacteriophages and phage cocktails, bacteriocins, inactivation of plant tissue degradation enzymes, phytochemicals, edible coatings. Moreover, they can be used either individually to limit the growth of bacteria in the food environment, or in combination with other methods in order to achieve maximum effect. This article discusses the main biological methods of combating pathogenic bacteria most commonly found in the food environment. The purpose of this review was to consider existing biological methods for processing plant objects, as well as to identify the advantages and disadvantages of each method.

Recent Advances in the Application of Edible Coatings for Shelf-Life Extension of Strawberries: A Review

Recent Advances in the Application of Edible Coatings for Shelf-Life Extension of Strawberries: A Review

Application of Edible Coating from Konjac Flour added with Chitosan on the Quality of Red Chili

Red chilies have a relatively short shelf life and are highly perishable. Red chili is one type of vegetable with a water content (60 - 90 %) at the time of harvest and an increase in respiration rate. Therefore, it is necessary to pack a coating that can reduce and suppress respiration and transpiration rates to prevent vegetable damage. One potential way to reduce the damage to red chilies is by applying edible coatings. Edible coating is one technique that can be developed and applied to maintain quality and extend the shelf life of red chili. This study aims to determine the quality characteristics of red chili (Capsicum annuum L) before and after coating edible coating. In addition, to analyze the effect of Konjac flour concentration on the quality characteristics of red chili (Capsicum annuum L) with the addition of chitosan and to find out the best treatment for the application of edible coating with the basic ingredients of Konjac flour with the addition of chitosan. This study used a completely randomized design (CRD) and three replications. The treatment in this study was the storage time of coated red chilies edible coating for 1, 3, 6, and 9 days. The results showed that the storage time of coated red chilies edible coating affects the pH, water content, weight loss, respiration rate, and color. The analysis of the characteristics of red chilies showed that the coating done on red chilies can reduce and suppress the process of respiration rate.

Ascorbic acid-enriched cactus mucilage coatings maintained quality attributes of roasted ‘Wichita’ pecan nuts under accelerated storage conditions

The potential of a cactus mucilage (CM)-based edible coating enriched with ascorbic acid (AA) for preserving microwave-roasted pecan nuts’ quality during accelerated storage was investigated. CM (3 %) was mixed with different concentrations of AA, which were 0.03, 0.015, and 0.09 %, to formulate edible coating solutions that were applied to microwave-roasted (700 W, 2.27 min) pecan nuts before accelerated storage for 25 days at 60 °C. Samples were taken at a 5-day interval to be analysed for colour properties (L = lightness, BI = browning index, and TCD = total colour difference), hardness, total yeast and mold, total flavonoids content (TFC), total phenolic content (TPC), ferric reducing antioxidant power (FRAP), DPPH radical scavenging activity, peroxidase (POD), and polyphenol oxidase (PPO) enzyme activities. Coating microwave-roasted pecan nuts with 3 % CM enriched with AA at low concentrations such as 0.015 % proved effective in preserving the colour, hardness, TPC, TFC, FRAP, and reducing the activities of POD and PPO enzymes. This study has demonstrated that CM enriched with AA edible coatings has the capacity to protect the quality and prolong the shelf-life of microwave-roasted pecan nuts.

Application of Silk Fibroin Nanoparticles based Edible Coating Material for Postharvestshelf-Life Extension and Preservation of Food Products

Nanotechnology is a burgeoning discipline that adapts to fresh and improved use in food systems relative to previous technologies, despite its broad application in agriculture, biochemistry, medicine, and several industries. By implementing innovative technologies, it is possible to efficiently incorporate them into many parts of food production, development, manufacturing, packaging, storage, and distribution. Nanoparticles occupies the most fundamentally advanced technology in nano-based food science. Using a broad range of nanostructured materials and nanomethods, such as liposomes, polymeric nanoparticles, nanoencapsulation, nanotubes, nanocomposites, packaging, and nanosensors. Silk Fibroin (SF), a biomacromolecule based on proteins, is very biocompatible, biodegradable, and has a low immunogenicity. Due to these characteristics, silk fibroin nanoparticles, or SFNPs, are beneficial across several sectors, including medical and food. The creation of SF-based nanoparticles as edible coating materials extends food shelf life and protects food components while also fortifying and supplementing nutrients. The phytochemical activities of SFNPs, including their antibacterial and antioxidant properties, are summarized in this review. The possible uses of silk fibroin nanoparticles in food, such as food additives and food packaging, which may be able to meet customers increasing demands about the food’s safety and nutritional value. The techniques of food preservation used to preserve or safeguard food quality are the major topic of this review article. Natural food preservatives are also discussed as a safer alternative to chemical preservatives for human consumption.

Edible coatings on postharvest quality of cherry tomatoes grown in organic and conventional systems

Cherry tomatoes belong to a promising new group of table cultivars, but show significant post-harvest quality losses, which can be reduced with edible coatings use, considered eco-sustainable. In view of the high perishability of tomatoes, the aim of this research was to evaluate the effect of different edible coatings on the shelf life of cherry tomatoes, cultivar Sweet Heaven, under organic and conventional cultivation. The experiment was conducted at the Instituto Federal Goiano, Campus Morrinhos, GO, Brazil, and the treatments were composed of coatings of chitosan, cassava starch, lactic acid and control (no coating). The samples were stored at a room with environment external temperature (± 27°C) for 20 days, arranged in a completely randomized design, with three replications. Every 2 days, the following were evaluated: fresh mass loss and moisture; pH, titratable acidity, soluble solids, lycopene, reducing sugar, vitamin C and ash; and molds and yeasts. Data were submitted to ANOVA and Tukey’s test (p<0.05). The organic system promoted greater shelf life and fruit quality of cherry tomatoes, compared to the conventional. The coating with chitosan provided longer shelf life of organic cherry tomatoes, compared to the other coatings studied, being a strong ally in reducing post-harvest waste and increasing the commercial value of the organic product, with economic strengthening for producers and traders, in addition to reduction of damage to the environment. Under conventional cultivation, the evaluated coatings were not efficient in increasing the shelf life of cherry tomatoes, requiring further studies for this condition.

Peach Gum Polysaccharide as an Additive for Thermoplastic Starch to Produce Water-Soluble Films

Thermoplastic starch (TPS) has gained considerable attention during the last few years in developing starch-based biodegradable food packaging materials or edible coatings due to its high availability and low cost. TPS is manufactured from starch plasticized with food-grade plasticizers, making it suitable for food contact applications. In addition, TPS is bio-based and biodegradable, which, from an environmental perspective, closes the circle of the circular economy. However, the industrial application of TPS is somewhat limited due to its poor mechanical performance and low water resistance. However, the low water resistance could increase the water sensitivity of TPS, which could be advantageous for coating application or food encapsulation. The present work aims to tailor the water sensitivity of TPS by adding peach gum polysaccharide to obtain water-soluble films. With this aim, peach gum polysaccharide (PGP) was extracted from peach gum (PG) using the thermal hydrolysis method. Films of TPS-PG and TPS-PGP were prepared and characterized by their water sensitivity and mechanical, microstructural, and thermal properties. The results show that PGP allows the obtaining of films with water sensitivities higher than 70% but also improves TPS elongation at break, making the material more suitable for application as film.

INNOVATIVE TECHNOLOGIES OF POST-HARVEST PROCESSING OF VEGETABLES AND FRUITS

Purpose. To analyze the current use of edible coatings for post-harvest processing of vegetables and fruits aimed at reducing losses and maintaining quality during storage. Results. Analysis of recent Ukrainian and foreign scientific and patent literature showed that the main advantages of coatings were based on such features as cost, availability, functionality, mechanical properties, optical properties, barrier capacity against gas flow, structural resistance to water and microorganisms, and sensory acceptability. They are used in combinations with bioactive compounds that confer additional functions on foods and extend their shelf lives. Conclusion. Transpirable coatings of fruits and vegetables slow down the post-harvest ripening processes in fresh products, preventing their further degradation and rotting. They are easier to use in packaging plants, require less investment and even outperform state-of-the-art packaging such as modified atmosphere packaging. Such protection mostly does not entail toxicological problems. Such coatings facilitate manufacturing and transport companies' work. Crops can stay in the field longer, continue to ripen, and can be harvested later because the risk of rot during transport and retail is reduced. In this way, the waste amount throughout agricultural production in general is decreased.

Are edible coatings (with or without essential oil/extract) game changers for maintaining the postharvest quality of strawberries? A meta-analysis

Strawberries have limited storage potential due to their sensitive structure, resulting in high postharvest losses during transportation and storage. This meta-analysis aimed to investigate the actual effect size of utilizing edible coatings (with or without essential oils and extracts) on maintaining the quality, appearance, and sensory acceptance of strawberries during postharvest storage. The effect of different categorical moderators including the presence or absence of essential oil/extract in the coating, the polymer type (polysaccharide, protein, combination of both), storage duration (1, 2, 3, and 4 weeks), and storage temperature (room temperature and cod storage) were also determined through random-effects model analysis. The potential publication bias was examined through funnel plot (Trim and Fill method), Rosenthal’s fail-safe number and Egger’s test. After full text screening based on inclusion/exclusion criteria, a total of 56 papers, including 115 studies were selected for meta-analysis. Based on the obtained results, coated strawberries exhibited significantly (p < 0.001) higher firmness (47.3 %), total acidity (19.9 %), sensory acceptance (64.8 %), chromacity (13.3 %) and the lower weight loss (-35.6 %) and decay percentage (-46.3 %) compared to uncoated ones. Incorporating essential oils into edible coating significantly increased chromacity (27.7 %) and total acidity (21.8 %) while adding extract significantly enhanced the retaining of firmness (90.3 %) and weight (39.4 %) in stored strawberries. The results of the current meta-analysis provide better understanding and insights into the efficiency of incorporating essential oils and extracts into edible coating for fruit, particularly strawberries.

Edible coating functionalized with ornamental plant extracts affect the postharvest quality of guava (Psidium guajava) during storage

Present study was carried out during 2021–23 at ICAR-Indian Agricultural Research Institute, New Delhi to investigate the efficacy of active edible coatings, incorporated with extracts from rose leaves and marigold petals in preserving the quality of mature green guava (Psidium guajava L.) cv. Allahabad Safeda during storage at both ambient (25±2°C) and cold (10±1°C) conditions. The coatings, particularly carboxy methyl cellulose combined with rose leaf extract (CMC+RL) demonstrated the highest effectiveness in minimizing per cent firmness reduction (PFR; 77.02% and 84.71%) compared to the control (89.95% and 89.73%) after 4 and 18 days of ambient and cold storage, respectively. Additionally, the coatings significantly influenced total soluble solids (TSS), total sugar content (TSC) and yellowness index (YI) showing potential in slowing down the fruit ripening. Moreover, the coatings demonstrated notable antioxidant activity with CMC+RL coating exhibited the highest activity. Furthermore, the coatings exhibited a substantial inhibitory effect on polygalactouronase (PG) activity, indicating a potential to mitigate cell wall degradation. Overall, the results highlight the promise of these biodegradable coatings as an alternative to synthetic preservatives in preserving postharvest quality and enhancing the shelf-life of guava fruits.

Single and combined effects of oregano leaf and clove oils on the reduction of salmonella enteritidis on chicken egg shells

Table eggs are versatile foodstuffs used in various food products. Eggs are often consumed or incorporated into other food products to enhance taste and nutrition and act as an emulsifying agent. Too often the consumption of contaminated eggs leads to foodborne illnesses in people. When whole eggs or egg products come into contact with contaminated surfaces or other contaminated eggs, pathogens can spread from one egg to another. Research has been conducted to uncover ways to protect whole eggs and their products from contamination by coating the egg’s exterior with edible coatings. Mineral oil, among other edible oils, is one such oil shown to be effective in reducing the bacteria in eggs when applied to the egg’s exterior. With the average consumer becoming more aware of the chemicals used in the preservation of food, some researchers have started to explore more natural solutions to minimize the contamination of food products. The use of essential oils to prevent contamination has been studied and analyzed for their antimicrobial properties in the inhibition of the growth of foodborne pathogens. The oils used in this current study are Oregano and Clove Oil. Both oils used individually and combined compared to a positive control showed no differences (p &gt; 0.05). Interestingly, when the oils were combined 1:1 there was a difference of 0.66 log in the survival bacterial counts compared to the positive control. However, this difference was also not significant (p &gt; 0.05).

A new active packaging system based on chickpea-based edible coatings added with microcapsules of Cosmos sulphureus Cav. flower extract.

The Cosmos sulphureus Cav. plant is studied for its high polyphenolic content with antioxidant properties. Its flowers, rich in phenolic acids, flavonoids, and tannins, hold promise as antioxidants in food preservation. The inclusion of these compounds in chickpea-based coatings with a previously studied preservative effect would be an excellent option as a food preservation method and microencapsulation addresses challenges like dispersion and degradation of polyphenols in the coating. The objective of this research was to evaluate the in vitro antioxidant activity of Cosmos sulphureus leaves, seed, and flower extracts and explore the protective effects of chickpea-based coatings containing microcapsules of flower polyphenolic extract on the chemical quality of stored roasted sunflower seeds during storage. The ethanolic leaf extract exhibited the highest antiradical activity, followed by the aqueous flower extract. After a storage period of 15 days, at 40 °C, the chickpea-based coatings effectively delayed lipid oxidation in the roasted sunflowers seeds, and the inclusion of polyphenolic microcapsules with 0.01% extract (SMC 0.01%) in the coating significantly improved the protective effect. By day 15 of storage, SMC 0.01% showed comparable peroxide value, conjugated dienes, and linoleic acid content to samples containing the synthetic antioxidant BHT (butylated hydroxytoluene). Samples that only contained chickpea-based coating and coating with polyphenolic microcapsules with 0.005% extract exhibited significantly greater reduction in fatty acid content compared to the 0.01% SMC treatment. The chickpea-based coating with polyphenolic microcapsules demonstrated antioxidant activity akin to synthetic BHT, offering a promising biopackaging solution for lipid-rich foods like roasted sunflower seeds. © 2024 Society of Chemical Industry.

Enhancement of Post-harvest Quality of Fresh Mandarins with Alginate-Based Edible Coating Containing Natamycin and Vanillin

Enhancement of Post-harvest Quality of Fresh Mandarins with Alginate-Based Edible Coating Containing Natamycin and Vanillin

Antibacterial properties of edible coatings from chitosan and young coconut shell liquid smoke

Abstract Liquid smoke-based edible coatings have garnered considerable attention in the food processing and post-harvest industry due to their environmentally friendly attributes and their ability to extend the shelf life of perishable goods. This study investigates the antimicrobial efficacy of edible coatings formulated using chitosan and young coconut shell liquid smoke against both gram-negative bacteria (Escherichia coli and Salmonella typhimurium) and gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus). The liquid smoke was produced via the pyrolysis of young coconut shells at temperatures of 300 (T1), 340 (T2), 380 (T3) and 420ºC (T4). The edible coatings were prepared by blending 2% (v/w) liquid smoke with varying chitosan concentrations of 0.5 % (Ch 0.5), 1% (Ch 1) and 1.5% (Ch 1.5). Antibacterial activity assessments were conducted using the disc diffusion method (Kirby Bauer). The findings reveal that the antibacterial efficacy of the edible coatings against each bacterial strain is influenced by both the pyrolysis temperature and the concentration of chitosan employed. Liquid smoke derived from T4 pyrolysis exhibited the highest inhibitory potential, except for Bacillus subtilis. Notably, the most pronounced antimicrobial activity against Salmonella typhimurium was observed with the T4Ch1.5 edible coating. Specifically, at T4Ch1.5, the inhibitory zones for Escherichia coli, Salmonella typhimurium, Bacillus subtilis, and Staphylococcus aureus were measured at 7.65 mm, 8.30 mm, 7.55 mm, and 7.23 mm, respectively. The results underscore the promise of edible coatings comprising a combination of chitosan and young coconut shell liquid smoke as potential candidates for preserving food and agricultural products, offering both protection and antibacterial properties.

Influence of various edible oil coatings on the shelf life of guava (Psidium guajava) Cv. Allahabad Surkha

Influence of various edible oil coatings on the shelf life of guava (Psidium guajava) Cv. Allahabad Surkha

Extending the shelf-life of refrigerated chicken fillets by using polymeric coating layer composed of ginger Zingiber officinale essential oil loaded-chitosan nanoparticles

AbstractThis study aims to evaluate the effect of coating chicken fillets with chitosan nanoparticles (CHN) loaded with ginger (Zingiber officinale) essential oil (GEO) on sensory characteristics, microbiological safety, and deterioration criteria; refrigerated at 4 °C. Furthermore, to determine whether different coatings could increase the storage period of chilled chicken fillets. Consequently, about 6 kg of chicken fillet were equally distributed into six groups. The first group being control (C), the second and third groups being ginger essential oil 0.5% (GEO 0.5%) and 1% (GEO 1%), the fourth group being chitosan nanoparticles alone (NCH 1%), the fifth and sixth groups were chitosan nanoparticles loaded with ginger essential oil 0.5% (NCHGO 0.5%), and 1% (NCHGO 1%). All groups were examined on the initial day of treatment (0-day) and every 4 days until the visible deterioration process appeared in each group. Results revealed that, coating chicken fillet with chitosan nanoparticles and ginger essential oil (NCHGO 1%) produced a powerful synergetic effect during refrigerated storage, as it could significantly inhibit microbial growth, decrease the rate of fat and protein deterioration, and improve sensory attributes. Interestingly, coated chicken fillet in refrigerator could last 28 days instead of 4 days. Ginger loaded-chitosan nanoparticles were employed to produce edible coatings as an efficient natural preservative and flavoring agent in poultry processing.

Shelf Life Extension of Fresh Cut Carrot by the Application of Cinnamon Extract Infused Edible Coating

The consumer demand for fresh cut fruits and vegetables is increasing rapidly owing to fast paced life style changes. The main problem with fresh cut fruits and vegetables is deterioration in term of color, taste, firmness etc. To solve these issues, researcher and processors have been using edible coatings to maintain quality of fresh cut commodities. Objective: To assess the potential effects of cinnamon extract infused edible coating formulated for shelf life extension of fresh cut carrots. Methods: Cinnamon extract was added as an antioxidant, aimed to aid in shelf life extension of fresh cut carrots. Cinnamon extract was obtained in an aqueous medium. The treatments were stored at 5oC for 21 days for shelf life study. The treatments were assessed for weight loss%, %acidity, TSS, firmness, color and ascorbic acid content at 7 days. Results: Coated treatments had better quality after storage period in term of wt. loss %, firmness and color, as compared to non-coated control treatments. Conclusions: Result suggests that edible coating enhanced with antioxidants have the potential to extend shelf life of fresh cut fruits and vegetables.

Insect-derived chitosan, a biopolymer for the increased shelf life of white and red grapes

Post-harvest water loss and microbial infections are the root cause of the rapid deterioration of fresh fruit after the picking process, with both environmental and economic implications. Therefore, it is crucial to find solutions that can increase the shelf life of fresh fruits. For this purpose, edible coatings, naturally derived and non-synthetic, are acknowledged as a safe strategy. Among polymeric coatings, chitosan is one of the most effective. In this work, this biopolymer, produced from chitin extracted from Hermetia illucens, an alternative and more sustainable source than crustaceans (the commercial one), was exploited to extend the shelf life of white and red grapes. Chitosan from H. illucens pupal exuviae, at 0.5 % and 1 % concentrations, was applied on both grapes, which were then stored at room temperature or 4 °C. The study of chemical-physical parameters such as weight loss, Total Soluble Solids and pH, demonstrated the effectiveness of the biopolymer, even better than crustacean chitosan. Moreover, the analysis of nutraceutical properties has demonstrated that this natural edible coating improves the quality of grapes, with beneficial effects for human health. The obtained results, therefore, confirmed the viability of using insect-chitosan as an alternative to crustaceans for the preservation of fresh food.

Enhancing the Quality of Ripened ‘Irwin’ Mangoes and the Shelf Life through Chitosan Edible Coating and Modified Atmosphere Packaging

Enhancing the Quality of Ripened ‘Irwin’ Mangoes and the Shelf Life through Chitosan Edible Coating and Modified Atmosphere Packaging

Edible Coating with Encapsulated Antimicrobial and Antibrowning Agents via the Emerging Electrospinning Process and the Conventional Spray Drying: Effect on Quality and Shelf Life of Fresh-Cut Potatoes

Edible Coating with Encapsulated Antimicrobial and Antibrowning Agents via the Emerging Electrospinning Process and the Conventional Spray Drying: Effect on Quality and Shelf Life of Fresh-Cut Potatoes