Evaluation of edible films and coatings formulated with cassava starch, glycerol, carnauba wax and stearic acid

The potential of carboxylmethyl cellulose from empty fruit bunch as versatile material in food coating: A review

The rising demand for food packaging has led to a growing interest in sustainable and eco-friendly food coatings. Carboxymethyl cellulose (CMC), being a versatile cellulose derivative produced from various lignocellulosic sources, has emerged in edible food coatings. This review evaluates the research trends on CMC production from empty fruit bunch (EFB) as a potential edible food coating material by systematic review approach. It explores sustainable pre-treatment for green cellulose and different CMC synthesis methods. The review compares CMC-based coatings to other materials, focusing on formulation processes, coating quality, safety, and commercial feasibility. The bibliometric analysis is performed to correlate food coating and CMC. As a result, the study discovered the rapid growth in research on edible food coatings made from CMC for various food industry applications. The green approach such as ozone pre-treatment appear as promising method for cellulose isolation from EFB to be used as raw material for CMC. The synthesis conditions of the treatment would affect the CMC characteristics and usage. Herein, utilizing CMC from cellulose EFB in coating formulation and on coated food shows different benefits. This review provides a road map for future research with potential to make important contributions to the food industry's long-term evolution.

Chitosan-based nanocomposite films with carnauba wax, rosin resin, and zinc oxide nanoparticles

This work aimed to develop edible emulsion-based barriers in the form of chitosan composite films, with a focus on assessing the impacts of carnauba wax, rosin resin, and zinc oxide nanoparticles on their properties. Six films were produced by casting using chitosan as polymer base and glycerol as plasticizer. Acetic acid and polysorbate 80 were also used to facilitate the dissolution and mixing of the components. The six filmogenic solutions contained chitosan at 1.2% w/v, wax or resin content with 0 or 0.6% m/v and ZnO with 0 or 0.05% m/v. The dried films were characterized according to their chemical, barrier, mechanical, thermal and optical properties. All treatments resulted in flexible films. Chitosan films appeared smoother and more uniform under SEM imaging, while carnauba wax films displayed roughness due to their hydrophobic nature. Wax and resin films were less transparent and water soluble than the chitosan-only films. On the other hand, the addition of ZnO in the formulations increased the solubility of the films. The sorption degree was in line with the solubility results, i.e., films with ZnO presented higher sorption degree and solubility values. All treatments showed low or non-light UV transmission, indicating that the films provide good barrier to UV light. In the visible light region, films of resin with ZnO showed the lowest transmittance values, hence offering a good barrier to visible light. Among the evaluated films, chitosan, and resin films with ZnO nanoparticles were more rigid and resistant to deformation. Overall, films produced with rosin resin and ZnO nanoparticles showed potential improvements in barrier, mechanical, thermal, and optical properties, mainly due to their low water solubility, good UV protection and low permeability to water vapor and oxygen, which are suitable for using in formulations, intended to produce edible films and coatings.

Lipid incorporated biopolymer based edible films and coatings in food packaging: A review

In the evolving landscape of food packaging, lipid-based edible films and coatings are emerging as a sustainable and effective solution for enhancing food quality and prolonging shelf life. This critical review aims to offer a comprehensive overview of the functional properties, roles, and fabrication techniques associated with lipid-based materials in food packaging. It explores the unique advantages of lipids, including waxes, resins, and fatty acids, in providing effective water vapor, gas, and microbial barriers. When integrated with other biopolymers, such as proteins and polysaccharides, lipid-based composite films demonstrate superior thermal, mechanical, and barrier properties. The review also covers the application of these innovative coatings in preserving a wide range of fruits and vegetables, highlighting their role in reducing moisture loss, controlling respiration rates, and maintaining firmness. Furthermore, the safety aspects of lipid-based coatings are discussed to address consumer and regulatory concerns.

Preparation and characterization of glyceryl stearate/cassava starch composite for wax therapy

Glyceryl stearate and cassava starch (CS) composites were prepared by an esterification process. Formulations containing starch at various concentrations were prepared, being 1, 1.5, 3, 5, 10, 15, 20, and 30 % by weight, respectively. The characteristics of pH, moisture content, FTIR, melting point, latent heat, thermal energy storage, and specific heat capacity of composites were elucidated. The optimal formulation contained 1 % w/w CS, this indicated that the composite was able to maintain its temperature for 9.4 ± 0.5 min, with a melting temperature of 51.9 ± 0.3 °C, solidification temperature of 36.1 ± 1.6 °C, latent heat of fusion of 120 ± 10 J/g, and latent heat of solidification of 126 ± 3 J/g, and specific heat capacity of 2.6 ± 0.2 J/g.K. New bonds were formed in the composite structure of glyceryl stearate and CS at these levels. The composite had a pH that was safe for contact with human skin and a moisture content that could be kept stable for a prolonged time. The innovation and the advantages of a composite materials: 1. The main components are derived from natural materials. 2. Costs effective 3. Sustainability 4. Safety, and 5. Efficacy. Therefore, composites have a high potential as are replacement for paraffin wax bath therapy.

Revolutionizing single-use food packaging: a comprehensive review of heat-sealable, water-soluble, and edible pouches, sachets, bags, or packets

Edible food packaging has emerged as a critical focal point in the discourse on sustainability, prompting the development of innovative solutions, notably in the realm of edible pouches. Often denoted as sachets, bags, or packets, these distinct designs have garnered attention owing to their water-soluble and heat-sealable attributes, tailored explicitly for single-use applications encompassing oils, instant or dry foods, and analogous products. While extant literature extensively addresses diverse facets of edible films, this review addresses a conspicuous void by presenting a consolidated and specialized overview dedicated to the intricate domain of edible pouches. Through a meticulous synthesis of current research, we aim to illuminate the trajectory of advancements made thus far, delving into critical aspects, including materials, production techniques, functional attributes, consumer perceptions, and regulatory considerations. By furnishing a comprehensive perspective on the potential, challenges, and opportunities inherent in edible pouches, our overarching aim is to stimulate collaborative endeavors in research, innovation, and exploration. In doing so, we aspire to catalyze the broader adoption of sustainable packaging solutions tailored to the exigencies of single-use applications.

Development of a novel 1-octen-3-ol-loaded agar/curdlan hydrogel for inhibiting peach fruit diseases

Our previous study found that 1-octen-3-ol fumigation treatment could effectively induce the resistance of peach fruit diseases. However, 1-octen-3-ol is a liquid fumigant, which is not conducive to storage and application. Herein, the gel of 1 % agar compound with 1 % curdlan was used as a novel material for covering 1-octen-3-ol. The interaction of agar and curdlan was promoted by adding 1-octen-3-ol, leading to a higher thermostability compared to single-component antibacterial gels. Moreover, 1-octen-3-ol resulted in changes in the internal structure and mechanical properties of gel to form a pore-like structure, which is beneficial to the retention and release of 1-octen-3-ol. Additionally, the 2 % agar gel containing 1-octen-3-ol had the best inhibitory effect on the mycelial growth of Monilinia fructicola and Rhizopus stolonifer in vitro, and the compound hydrogel of 1 % agar and 1 % curdlan with 1-octen-3-ol could most effectively inhibit brown rot and soft rot caused by these two pathogens in vivo. Overall, the data indicated that the novel 1-octen-3-ol-loaded agar/curdlan hydrogels could effectively retain and release 1-octen-3-ol, and induce the resistance of peach fruit diseases.

Sustainable Bioplastics for Food Packaging Produced from Renewable Natural Sources

It is crucial to find an effective, environmentally acceptable solution, such as bioplastics or biodegradable plastics, to the world's rising plastics demand and the resulting ecological destruction. This study has focused on the environmentally friendly production of bioplastic samples derived from corn starch, rice starch, and tapioca starch, with various calcium carbonate filler concentrations as binders. Two different plasticizers, glycerol and sorbitol, were employed singly and in a rich blend. To test the differences in the physical and chemical properties (water content, absorption of moisture, water solubility, dissolution rate in alcohol, biodegradation in soil, tensile strength, elastic modulus, and FT-IR) of the produced samples, nine samples from each of the three types of bioplastics were produced using various ratios and blends of the fillers and plasticizers. The produced bioplastic samples have a multitude of features that make them appropriate for a variety of applications. The test results show that the starch-based bioplastics that have been suggested would be a better alternative material to be used in the packaging sectors.

Edible Film Casting Techniques and Materials and Their Utilization for Meat-Based Product Packaging

According to a profusion of academic studies on the use of organic materials or biopolymers as key components, the current trajectory of food packaging techniques is showing a positive inclination. Notably, one such biopolymer that has attracted much attention is edible film. The biopolymers that have been stated as constitutive components are composed of polysaccharides, lipids, proteins, or a combination of these, which work together to reinforce one another's properties and create homogenous mixtures. An edible film provides a clear, thin layer that encases foodstuffs, including their packaging. The production and use of edible film have recently been the focus of much research in the field of food polymers. Extending the shelf life of food goods is the goal of this research. Given their great susceptibility to change brought on by outside forces or pollutants, which may result in oxidative rancidity, the proper storage of nutrient-dense food items, particularly meat products, deserves careful study. Many edible films have been found to contain active ingredients, such antimicrobials or antioxidants, that can successfully prevent the spoiling of meat products, a process that can happen in a short amount of time. Surprisingly, a number of scholarly examinations reveal that edible film may be cooked alongside meat because of its organic makeup. We hope that the use of edible film will lead to a more environmentally responsible method of food packaging than has previously been possible.

Self-assembled fatty acid crystalline coatings display superhydrophobic antimicrobial properties

Superhydrophobicity is a well-known wetting phenomenon found in numerous plants and insects. It is achieved by the combination of the surface's chemical properties and its surface roughness. Inspired by nature, numerous synthetic superhydrophobic surfaces have been developed for various applications. Designated surface coating is one of the fabrication routes to achieve the superhydrophobicity. Yet, many of these coatings, such as fluorine-based formulations, may pose severe health and environmental risks, limiting their applicability. Herein, we present a new family of superhydrophobic coatings comprised of natural saturated fatty acids, which are not only a part of our daily diet, but can be produced from renewable feedstock, providing a safe and sustainable alternative to the existing state-of-the-art. These crystalline coatings are readily fabricated via single-step deposition routes, namely thermal deposition or spray-coating. The fatty acids self-assemble into highly hierarchical crystalline structures exhibiting a water contact angle of ∼165° and contact angle hysteresis lower than 6°, while their properties and morphology depend on the specific fatty acid used as well as on the deposition technique. Moreover, the fatty acid coatings demonstrate excellent thermal stability. Importantly, this new family of coatings displays excellent anti-biofouling and antimicrobial properties against Escherichia coli and Listeria innocua, used as relevant model Gram-negative and Gram-positive bacteria, respectively. These multifunctional coatings hold immense potential for application in numerous fields, ranging from food safety to biomedicine, offering sustainable and safe solutions.

Effects of beeswax emulsified by octenyl succinate starch on the structure and physicochemical properties of acid-modified starchfilms

This work aimed to develop a novel strategy to modulate the distribution of beeswax in acid-modified starch films via tuning octenyl succinate starch (OSS) ratios and to elucidate their structure-property relationships. The apparent viscosity and storage modulus of the film-forming solution decreased with the increase of OSS ratio. Attenuated total reflectance-fourier transform infrared (ATR-FTIR) spectroscopy revealed that the hydrogen bond in the film-forming network was cleaved with the presence of OSS. Scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffraction (XRD) demonstrated that OSS ratio had an obvious effect on the formation and distribution of beeswax crystal particles. Uniform distribution of beeswax effectively enhanced the hydrophobicity and water barrier properties of films and performed preferable elongation at break but at the expense of tensile strength and optical properties. The films with higher OSS ratio (>12 %) presented higher thermal stability. This study provides new information on the rational design of emulsified films to obtain desirable physicochemical properties by tuning the distribution of beeswax.

Cassava and banana starch modified with maleic anhydride-poly (ethylene glycol) methyl ether (Ma-mPEG): A comparative study of their physicochemical properties as coatings

This study proposes a simple route to obtain starch grafted copolymers from cassava and banana starches chemically modified with amphiphilic maleic anhydride-poly (ethylene glycol) methyl ether (Ma-mPEG). The starches were extracted from cassava (StC) and banana (StB) pulp and characterized by FTIR spectroscopy, amylose content, scanning electron microscope (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and average molecular weight. Starches were chemically modified with amphiphilic Ma-mPEG in three mass ratios 1:1, 1:2 and 1:3. Thermal behavior and interactions of Ma-mPEG/starch in the St-g-(Ma-mPEG) copolymers were studied by DSC and TGA. The T_g values showed a higher plasticizer effect in the copolymers obtained from StC. Films were formed from StC-g-(Ma-mPEG) and StB-g-(Ma-mPEG) copolymers, thermal and morphological properties were studied. An increase in the mass ratios of Ma-mPEG and the absence of the glycerol in the formulations formed homogeneous films. StC-g-(Ma-mPEG) 1:3 with 2% concentration showed a potential use as coating in strawberries, presenting a lower weight loss (15.5 ± 5.7%) than the control sample (18.6 ± 3.3%).

Impact of Biodegradable Materials on the Quality of Plums

Edible starch-based materials have shown a positive impact on quality parameters. In this study, plums (Prunus domestica cv. Jojo) were divided into five groups: a control, two coating treatments (starch and starch-whey protein (80–20%), and two film systems (starch and starch-whey protein (80–20%). Biodegradable packaging, particularly the coating treatment, had no negative effect on color parameters. After 28 days of performed tests, firmness was boosted with starch and starch-whey protein (80–20%) films. With the coated materials, there was no significant difference compared to control group. The lowest transpiration velocity was of plums wrapped in starch films. In the case of respiration rate, no significant difference was observed between the packaging and control samples. After the conducted trials, the weight loss of untreated plums was at 10%, while 5% of weight loss was noticed for plums wrapped in starch materials, and around 6% was noticed for the other materials. Oxygen permeability was higher for S-WP films, the thickness of S and S-WP films were comparable and thickness of starch coating was around 60% higher than S-WP. Both films have an affinity to water and both show typical behavior of water vapor sensitive hydrophilic biopolymers. The starch film with the addition of 20% of proteins increased the resistance of gas exchanges, which represents one of its great benefits.

Degradation, migration, and removal of trichlorfon on harvested apples during storage at room temperature

Dissipation of an organophosphorus pesticide, trichlorfon, in natural and waxed apples during storage was studied. The results showed that the trichlorfon content in natural and waxed apples decreased by 85% and 64%, respectively, during storage. The morphology of the surface film was dense and regular, which resulted in a higher water vapor resistance and a lower respiration rate in the waxed apples. This indicates that waxing affected the dissipation of pesticide residues in the apple storage environment, increasing food safety risk. Ozone was used to remove the residual pesticides on the apple surface. The trichlorfon degradation rate reached 73%. The ozone treatment had no effect on the surface color of the apple, which means that the fruit can be pre-treated with ozone prior to waxing or storage.

Effect of palm wax on the mechanical, thermal, and moisture absorption properties of thermoplastic cassava starch composites

Thermoplastic starch is a potentially sustainable and biodegradable material. However, it possesses some limitations in terms of mechanical performance and high moisture sensitivity. In this current work, the characteristics of thermoplastic cassava starch (TPCS) containing palm wax at various loading were evaluated. TPCS was prepared via hot pressing by varying the ratios of palm wax (2.5, 5, 10, and 15 wt%). Next, characterization via scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), mechanical, water solubility, thickness swelling and moisture absorption tests, were conducted on the samples. The findings showed that incorporating starch-based thermoplastics with palm wax has remarkably improved mechanical characteristics of the thermoplastic blends. Besides, the morphology of the samples demonstrated irregular and rougher cleavage fracture after palm wax addition. FT-IR indicated the existence of intermolecular interaction between TPCS and palm wax with the intermolecular hydrogen bonds that existed between them. The thermal stability of TPCS has improved with rising palm wax content. The incorporation of 15 wt% palm wax resulted in the lowest moisture absorption value among the samples. Overall, the developed TPCS/palm wax with improved mechanical and moisture resistance characteristics has the potential to be used as biodegradable materials.

Innovations in applications and prospects of bioplastics and biopolymers: a review

Non-biodegradable plastics are continually amassing landfills and oceans worldwide while creating severe environmental issues and hazards to animal and human health. Plastic pollution has resulted in the death of millions of seabirds and aquatic animals. The worldwide production of plastics in 2020 has increased by 36% since 2010. This has generated significant interest in bioplastics to supplement global plastic demands. Bioplastics have several advantages over conventional plastics in terms of biodegradability, low carbon footprint, energy efficiency, versatility, unique mechanical and thermal characteristics, and societal acceptance. Bioplastics have huge potential to replace petroleum-based plastics in a wide range of industries from automobiles to biomedical applications. Here we review bioplastic polymers such as polyhydroxyalkanoate, polylactic acid, poly-3-hydroxybutyrate, polyamide 11, and polyhydroxyurethanes; and cellulose-based, starch-based, protein-based and lipid-based biopolymers. We discuss economic benefits, market scenarios, chemistry and applications of bioplastic polymers.

Edible Films on Meat and Meat Products

In 2018, the worldwide consumption of meat was 346.14 million tonnes, and this is expected to increase in the future. As meat consumption increases, the use of packaging materials is expected to increase along with it. Petrochemical packaging materials which are widely used in the meat processing industry, take a long time to regenerate and biodegrade, thus they adversely affect the environment. Therefore, the necessity for the development of eco-friendly packaging materials for meat processing, which are easily degradable and recyclable, came to the fore. The objective of this review is to describe the application of natural compound-derived edible films with their antioxidant and antibacterial activities in meat and meat products. For several decades, polysaccharides (cellulose, starch, pectin, gum, alginate, carrageenan and chitosan), proteins (milk, collagen and isolated soy protein) and lipids (essential oil, waxes, emulsifiers, plasticizers and resins) were studied as basic materials for edible films to reduce plastic packaging. There are still high consumer demands for eco-friendly alternatives to petrochemical-based plastic packaging, and edible films can be used in a variety of ways in meat processing. More efforts to enhance the physiological and functional properties of edible films are needed for commercial application to meat and meat products.

An Extensive Review of Natural Polymers Used as Coatings for Postharvest Shelf-Life Extension: Trends and Challenges

Global demand for minimally processed fruits and vegetables is increasing due to the tendency to acquire a healthy lifestyle. Losses of these foods during the chain supply reach as much as 30%; reducing them represents a challenge for the industry and scientific sectors. The use of edible packaging based on biopolymers is an alternative to mitigate the negative impact of conventional films and coatings on environmental and human health. Moreover, it has been demonstrated that natural coatings added with functional compounds reduce the post-harvest losses of fruits and vegetables without altering their sensorial and nutritive properties. Furthermore, the enhancement of their mechanical, structural, and barrier properties can be achieved through mixing two or more biopolymers to form composite coatings and adding plasticizers and/or cross-linking agents. This review shows the latest updates, tendencies, and challenges in the food industry to develop eco-friendly food packaging from diverse natural sources, added with bioactive compounds, and their effect on perishable foods. Moreover, the methods used in the food industry and the new techniques used to coat foods such as electrospinning and electrospraying are also discussed. Finally, the tendency and challenges in the development of edible films and coatings for fresh foods are reviewed.

Effect of glycerol concentration and carboxy methyl cellulose on biodegradable film characteristics of seaweed waste

Eucheuma cottonii waste seaweed has high cellulose content. Therefore, it could be potentially used as a raw material for biodegradable films to replace plastic. A plastic film is its moisture resistance, and this property allows plastic films to be used as packaging materials and biodegraded by microbes. This research aims to obtain a concentration of glycerol and Carboxy Methyl Cellulose (CMC) to obtain the best biodegradable film characteristics from E. cottonii seaweed waste. This study was conducted in factorial by using a complete randomized block design with two factors: glycerol concentration and CMC concentration. Each treatment has three levels and three replications (3 × 3). The first factor was glycerol concentration: 0.25% (G1), 0.5% (G2), and 0.75% (G3). The second factor included concentrations of 1% CMC (C1), 2% CMC (C2), and 3% CMC (C3). Then, Tensile Strength (TS), thickness, solubility, and elongation were observed. Functional group analysis was conducted by Fourier-transform infrared spectroscopy and biodegradability test. The results showed that the addition of glycerol concentrations of 0.5 and 0.7% and CMC from 1 to 3% produced tensile strengths of 23–39 MPa. These values are proportional to the tensile strength of Poly Tetra Fluoro ethyne (PTFE) and Poly Propylene (PP) synthetic plastics released by Dotmar Engineering Plastics. The biodegradability test showed that the produced biodegradable films decomposed after 14 days.

The synergistic effects of zinc oxide nanoparticles and fennel essential oil on physicochemical, mechanical, and antibacterial properties of potato starch films

The purpose of this study was to evaluate the effects of a combination of zinc oxide (ZnO-N) nanoparticles and fennel essential oil (FEO) on the functional and antimicrobial properties of potato starch films. Films based on potato starch containing a combination of ZnO-N (1, 3, and 5%(w/w)) and FEO (1, 2, and 3% (w/w)) produced by casting method and water solubility, water absorption capacity (WAC), barrier properties, mechanical properties, color indexes, and antimicrobial activity of the films against Staphylococcus aureus, Escherichia coli, and Aspergillus flavus were studied. The combination of ZnO-N and FEO had a significant decreasing effect on solubility, WAC, water vapor and oxygen permeability, elongation, and L* index. These additives had an increasing impact on tensile strength, Yang's modulus, and a* and b* indexes (p < .05). By increasing the concentration of ZnO-N and FEO, the antimicrobial activities of bionanocomposite films significantly increased (p < .05). Both ZnO-N and FEO had a significant effect in this respect, although the effects of ZnO-N were more significant. In conclusion, an excellent synergistic effect of ZnO-N and FEO was observed in potato starch films.

Advantages and challenges of Pickering emulsions applied to bio-based films: a mini-review

The strategy of adding hydrophobic compounds to bio-based films (usually based on hydrophilic matrices), forming films containing emulsions, is a technique that has been used to improve some physical properties (such as reducing water solubility and water vapor permeability) and / or to impart properties, such as antioxidant and antimicrobial effects by carrying hydrophobic active components that would otherwise be insoluble in hydrophilic matrices. Although Pickering emulsions have been reported as presenting greater stability when compared with surfactant-stabilized emulsions, little is known about the drying stability of Pickering emulsions (which is important for film applications). Anyway, several studies have indicated that Pickering emulsions are interesting systems to improve the water vapor barrier properties of bio-based films and coatings, and to act as carriers of active hydrophobic components. On the other hand, the tensile properties of those films are usually impaired by the presence of Pickering emulsions. The objective of this review is to present recent developments and future perspectives in bio-based films loaded with Pickering emulsions. © 2020 Society of Chemical Industry.

Effect of plasticizers on physical, thermal, and tensile properties of thermoplastic films based on Dioscorea hispida starch

This study examines the effects of varying the concentrations of sorbitol (S) and glycerol (G) on the physical, morphological, thermal, and mechanical properties of Dioscorea hispida, starch-based films. In this context, the films of Dioscorea hispida starch were developed using solution casting technique with glycerol (G), sorbitol (S), and a mixture of sorbitol-glycerol (SG) as plasticizers at the ratios of 0, 30, 45, and 60 wt%. The films' moisture contents were increased when increasing the plasticizer contents. The tensile strengths were decreased, but elongations at break were increased; 7.38%-11.54% for G-plasticized films, 10.17%-15.76% for S-plasticized films, and 14.41%- 16.10% for SG-plasticized films with increasing plasticizer concentrations of the film samples. Varying plasticizer concentrations exhibited a minor effect on the S-plasticized film's thermal properties. Significant decrement in the glass transition temperatures of Dioscorea hispida starch films was observed when the plasticizer contents were raised from 30% to 60%. Significantly, the present work has shown that plasticized Dioscorea hispida starch can be considered a promising biopolymer for the applications of biodegradable films.

Edible Films and Coatings Formulated with Arrowroot Starch as a Non-Conventional Starch Source for Plums Packaging

Increasing environmental awareness has promoted an interest in alternative strategies to common plastics obtained from fossil sources, stimulating research on the use of biodegradable and edible films/coatings obtained from renewable sources such as arrowroot starch. This research work aimed to evaluate the use of arrowroot starch on the formation of edible films and coatings. Increasing the concentration of arrowroot starch (from 1% to 5%, mass/mass) in the film produced by casting resulted in increased water vapor permeability (from 2.20 to 3.68 g mm/m2 day kPa), moisture content (3.22% to 7.95%), increased thickness (from 0.029 to 0.101 mm), and decreased solubility in water (from 22.45% to 13.89%). The films were homogeneous, transparent and manageable, with the exception of the film with 1% starch. Film-forming solutions at concentrations of 0%, 2%, and 4% (mass/mass) of arrowroot starch were prepared and applied to plums to evaluate post-harvest behavior when stored at 25 and 5 °C for 35 days. The 2% coating adhered well to the plums’ surfaces, was bright and was effective in reducing mass loss and respiratory rate, associated with storage temperature of 5 °C. The 4% coating presented an opaque and flocculated appearance.

Optimization of Gum Arabic and Starch-Based Edible Coatings with Lemongrass Oil Using Response Surface Methodology for Improving Postharvest Quality of Whole “Wonderful” Pomegranate Fruit

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.

Development of quaternary nanocomposites made up of cassava starch, cocoa butter, lemongrass essential oil nanoemulsion, and brewery spent grain fibers

We report on production of novel quaternary nanocomposite films based on thermoplastic starch (TPS, 8% w/v) derived from cassava, cocoa butter, (CB, 30% wt.%), and lemongrass essential oil (LEO, 1:1) nanoemulsions reinforced with different concentrations of brewery spent grain (BSG, 5 or 10 wt.%) fibers, by continuous casting. The chemical composition, the morphological, thermal, mechanical properties, film barrier, biodegradability in the vegetable compound, in addition to the application in chocolates, have been widely studied. The addition of CB, LEO, and BSG caused relevant changes in the starch-based films, such as increased extensibility (from 2.4-BSG5 to 9.4%-BSG10) and improved barrier to moisture (2.9 and 2.4 g.mm.kPa^-1 .h^-1 .m^-2 ). Contrastingly, the thermal stability of the starch film was slightly decreased. The biodegradability of the herein developed quaternary nanocomposite films was the same as that of TPS films, eliminating concerns on the supplementation with active ingredients that are expected to have some biocidal effect. Despite checking antimicrobial activity only by contact under the biocomposites, chocolates packed with the films were well accepted by consumers, especially the samples of white chocolate stored in the BSG5 biocomposite. Overall, this new approach towards quaternary active, biodegradable films produced in a pilot-scale lamination unit was successful in either improving or at least maintaining the essential properties of TPS-based films for food packaging applications, while providing them with unique features and functionalities. PRACTICAL APPLICATION: This contribution relates to new approach toward quaternary films produced in a pilot-scale lamination unit. It relates to sustainability as it is both biodegradable and based on plant biomass, as well as produced via a clean, through high-yield process. The four components of the edible films we developed provide it with good in properties performance, as both a passive barrier (i.e. purely physical), and active, related to the sensory attributes of food, essential to be applied in food packaging. The valorization of a BSG also adds to the relevance of our contribution within the circular bioeconomy framework.

Effects of ultrasonication on the properties of maize starch/stearic acid/ sodium carboxymethyl cellulose composite film

Ultrasonic treatment can improve the compatibility between a hydrophobic material and a hydrophilic polymer. The light transmittance, crystalline structure, microstructure, surface morphology, moisture barrier, and mechanical properties of a composite film with or without ultrasonication were investigated. Ultrasound increases the film's light transmittance, resulting in a film that has good transparency. Ultrasonication did not change the crystalline structure of the polymer film, but promoted V-type complex formation. The surface of the film became smooth and homogeneous after the film-form suspension underwent ultrasonic treatment. Compared to the control film, after ultrasonication at 70% amplitude with a duration of 30 min, the average roughness and maximum roughness declined from 212 nm to 17.6 nm and from 768.7 nm to 86.5 nm, respectively. The composite film with ultrasonication exhibited better tensile and moisture barrier properties than the nonsonicated film. However, long-term and strong ultrasonication will destroy the polymer structure to some extent.

Synthesis and characterization of starch based bioplatics using varying plant-based ingredients, plasticizers and natural fillers

With the ever-increasing demand of plastics in the world and their consequent disastrous effects on environment, a suitable environmental-friendly substitute like bioplastics/biodegradable plastics is the need time. This study centers on green-production of a variety of bioplastic samples from (1) banana peel starch (BPP) and (2) a composite of banana peel starch, cornstarch and rice starch (COM) with varying amounts of potato peel powder and wood dust powder as fillers, respectively. Two different plasticizers - Glycerol and Sorbitol - have been utilized separately and in a 1:1 combination. A total of 12 samples of each of two types of bioplastics were made using multiple amounts and combinations of the fillers and plasticizers, to test the differences in the physical and chemical characteristics (moisture content, absorption of water, solubility in water, solubility in alcohol, biodegradation in soil, tensile strength, Young's modulus and FT-IR) of the produced samples due to their different compositions. The differences in the properties of the bioplastic samples produced make them suitable for usage in many different applications. All 24 of the samples produced were synthesized using natural and environmentally safe raw material and showed biodegradation, thus proving to be a good alternative to the conventional plastics.

Effects of Candelilla and Carnauba Wax Incorporation on the Functional Properties of Edible Sodium Caseinate Films

The aim of this study was to evaluate the effects of candelilla (CAN) or carnauba wax (CAR) incorporation on functional properties of edible sodium caseinate (CAS) films. Glycerol and Tween-80 were used as the plasticizer and the emulsifier, respectively. The results showed that the incorporation of waxes increased film opacity, total color differences (∆E), and mechanical resistance and reduced film lightness, water vapor permeability (WVP), and elongation at break. Scanning electron microscopy showed heterogeneous structure of emulsion films with regular distribution of lipid particles. A different internal arrangement was observed as a function of the film composition with both layered and incorporated film structure. Films containing candelilla wax exhibited more regular lipid reorganization, which resulted in better water vapor barrier efficacy and mechanical resistance in comparison to control films. The presence of Tween-80 resulted in better dispersion of lipid particles in film-forming solutions and lower water solubility, lightness, film opacity, and water vapor permeability, whereas the total color differences (∆E) were significantly larger and the improvement in mechanical properties was also achieved.

Edible Films of Whey and Cassava Starch: Physical, Thermal, and Microstructural Characterization

The present work aimed to obtain and characterize edible films produced with liquid whey and cassava starch. The films were produced with different proportions of whey (63.75–67.50%) and cassava starch (7.50–11.25%) and characterized in relation to physical, thermal, and microstructural properties. The films showed reduced solubility with increasing concentrations of cassava starch, and those with the highest proportions of whey were more stable to thermal decomposition. The increase in concentration of cassava starch altered the microstructure of the films, making them more irregular and with an accumulation of matter. The production of biodegradable polymer blend films is an important step in the development of films for use in packaging, with the formulation of 67.50/7.50% whey/cassava starch being the best film for continued future work.

Improvement of Andean Blueberries Postharvest Preservation Using Carvacrol/Alginate-Edible Coatings

Edible coatings are attractive strategies for blueberries postharvest preservation. In this work, carvacrol/alginate coatings were developed for application on Andean blueberries. Coating formulations were prepared based on blends of sodium alginate (2% w/v), carvacrol (0%, 0.03%, 0.06% or 0.09%), glycerol, and water and applied to the fruits by dip-coating. Then, the fruits were immersed in a calcium batch to induce a crosslink reaction. Changes in the physicochemical and microbiological characteristics of the blueberries were monitored during 21 days of storage at 4 °C. Coated blueberries were better preserved throughout the 21 days of storage because of their lower respiration rate and water loss, in comparison with the uncoated ones. Besides, the coatings enhanced the appearance and the gloss of the fruits. Control fruits showed a significant decrease in the firmness, while, in the coated fruits, this critical postharvest quality was preserved during the entire storage. Coating formulations with 0.09% of carvacrol was the most effective in preventing mesophilic aerobic bacteria and molds/yeasts growth on the fruits during the storage. Edible carvacrol/alginate coatings can be considered as a useful alternative to complement the benefits of refrigerated storage by delaying post-harvest spoilage of Andean blueberries.

Development and evaluation of edible films based on cassava starch, whey protein, and bees wax

Films and edible coatings based on biopolymers have been developed as a packaging, which can be obtained from biodegradable materials and have properties similar to common plastics. These edible materials have many applications in the food industry, preventing mass transfer between the product and the surrounding environment. The objective of this study was to develop and evaluate the physicochemical and mechanical properties of edible films based on cassava starch (CS), whey protein (WP), and beeswax (BW). Response surface methodology has been used and the experiments were carried out based on face-centred composite design. On the other hand, three CS-based controls were formulated to evaluate the effect of the inclusion of WP and BW. The optimization of multiple responses established the optimal formulation: CS (3.17 %), WP (1.30 %), BW (0.50 %), presenting the following response variables: tensile stress (1.92 MPa), elongation (40.4 %), Young's modulus (42.1 MPa), water vapor permeability 1.79 × 10^-11 (g mm/s cm² Pa), swelling capacity (300.3 %), thickness (0.128 mm), moisture content (6.74 %), and colour: lightness (89.9), chromaticity a∗ (-1.8), chromaticity b∗ (7.7), saturation (9.9), tone (101.1°), and yellowness index (17.7). The selection and evaluation of this optimal formulation are essential because it is the material that shows the best possible mechanical and physicochemical properties using the studied components. The results, especially its good mechanical properties and low permeability to water vapour, would allow its application as a coating for fruits, vegetables, among others, effectively delaying its weight loss due to dehydration.

Edible Films Based on Black Chia (Salvia hispanica L.) Seed Mucilage Containing Rhus microphylla Fruit Phenolic Extract

Functional films based on black chia (Salvia hispanica L.) seed mucilage (BCm) containing Rhus microphylla (Rm) fruit phenolic extract were built and characterized. A hydro-alcohol extract (HAE) of Rm was incorporated as the bioactive agent due to its noteworthy phenolic profile, and good antioxidant and antifungal activities. The effects of the BCm concentration (0.2% and 0.4%, w/v), HAE incorporation, and their interaction with glycerol (1.0%, w/v) and calcium chloride (0.05%, w/v) on the films’ physicochemical properties were evaluated. The filmogenic solutions successfully fitted to the Herschel–Bulkley model (R2 < 0.999), exhibiting a pseudoplastic and shear thinning character, typical of polymer solutions. Interestingly, their rheological properties were not (p > 0.05) changed by the HAE addition, but their surface tension was enhanced (p < 0.05), which could favor their coating ability. The polyanionic nature of the systems (zeta potential-Zp values from −26.9 to −33.3 mV) allowed them to interact with Ca2+ cations, thus forming stable and resistant films. All the films showed low water solubility (15.0% to 22.3%) and high permeability (3.7 to 4.0 × 10−10 g m−1 s−1 Pa−1), as well as high biodegradability (moisture content from 66.0% to 80.9%); although the moisture content was reduced (p < 0.05) with HAE addition. The combination of higher BCm ratio and HAE addition (BCm0.4+Rm) led to a more resistant, thick, opaque, and dark film compared with the others obtained. This study reveals the BCm-based films’ potential, highlighting those with HAE, representing a novel alternative to improve the quality of food products.