Edible candelilla wax coating with fermented extract of tarbush improves the shelf life and quality of apples

Recent advances in the preservation of postharvest fruits using edible films and coatings: A comprehensive review

In recent years, there has been considerable growth in the creation of edible films and coatings, which is predicted to have a major impact on fruit quality in the coming years. Consumers want fresh fruits that are pesticide-free, good quality, high nutritional value, and a long shelf life. The use of edible coatings and films on fruits is an environmentally dependable approach to a creative solution to this problem. The application, recent trends, and views of coatings and edible films, as well as their impact on fruit quality, are presented in this article, along with a knowledge of their key roles and benefits. According to numerous studies, natural polymers are highly suited for use as packaging material for fresh fruits and can often be a viable alternative to synthetic chemicals. Plasticisers, surfactants, cross-linkers, antimicrobial agents, functional additives, nanoparticles, and fruit and vegetable residues can be used to alter the properties of edible coatings.

Advances in apple packaging: a review

Apple (Malus domestica) belongs to the family Rosaceae. It is one of the most commonly cultivated fruit in all temperate zones of the world and holds an equally important place in the global economy. Apple is a climacteric fruit and undergoes metabolic changes even after the harvest and thus prone to post-harvest losses. The packaging of apples plays an important role in extending the shelf life of the apples and also maintains the quality during distribution and transport. The prime role of packaging is to contain the food commodity and protect the enclosed product from external damage. But other functions such as traceability, convenience and temper evidence are of secondary importance. Different packaging techniques are employed for the packaging of apples which include both conventional (wooden boxes, corrugated fiber boxes, crates) and non-conventional packaging like modified atmosphere packaging (MAP), active packaging, edible coatings, etc.

Biodegradable active packaging: Components, preparation, and applications in the preservation of postharvest perishable fruits and vegetables

The consumption of fresh fruits and vegetables is restricted by the susceptibility of fresh produce to deterioration caused by postharvest physiological and metabolic activities. Developing efficient preservation strategies is thus among the most important scientific issues to be urgently addressed in the field of food science. The incorporation of active agents into a polymer matrix to prepare biodegradable active packaging is being increasingly explored to mitigate the postharvest spoilage of fruits and vegetables during storage. This paper reviews the composition of biodegradable polymers and the methods used to prepare biodegradable active packaging. In addition, the interactions between bioactive ingredients and biodegradable polymers that can lead to plasticizing or cross-linking effects are summarized. Furthermore, the applications of biodegradable active (i.e., antibacterial, antioxidant, ethylene removing, barrier, and modified atmosphere) packaging in the preservation of fruits and vegetables are illustrated. These films may increase sensory acceptability, improve quality, and prolong the shelf life of postharvest products. Finally, the challenges and trends of biodegradable active packaging in the preservation of fruits and vegetables are discussed. This review aims to provide new ideas and insights for developing novel biodegradable active packaging materials and their practical application in the preservation of postharvest fruits and vegetables.

Candelilla Wax Extracted by Traditional Method and an Ecofriendly Process: Assessment of Its Chemical, Structural and Thermal Properties

A comparative study was carried out on the chemical, structural and thermal properties of candelilla wax from four wax-producing communities in Mexico, which was obtained by two extraction processes, the conventional one using sulfuric acid (SA) and an eco-friendly alternative process using citric acid (CA) as the extracting agent. The waxes were analyzed by basic chemistry (acidity, saponification, ester indexes, and others), color, Fourier transform infrared spectroscopy (FTIR), Raman micro-spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and hardness and brittleness measurements. The waxes obtained by the environmentally friendly process showed differences in their physicochemical properties when compared to waxes from the conventional process. In addition, they showed some improvements, such as lighter shades and harder waxes, suggesting that the new environmentally friendly process is a viable option.

Natural Polymers Used in Edible Food Packaging—History, Function and Application Trends as a Sustainable Alternative to Synthetic Plastic

In this review, a historical perspective, functional and application trends of natural polymers used to the development of edible food packaging were presented and discussed. Polysaccharides and proteins, i.e., alginate; carrageenan; chitosan; starch; pea protein, were considered. These natural polymers are important materials obtained from renewable plant, algae and animal sources, as well as from agroindustrial residues. Historically, some of them have been widely used by ancient populations for food packaging until these were replaced by petroleum-based plastic materials after World War II. Nowadays, biobased materials for food packaging have attracted attention. Their use was boosted especially because of the environmental pollution caused by inappropriate disposal of plastic packaging. Biobased materials are welcome to the design of food packaging because they possess many advantages, such as biodegradability, biocompatibility and low toxicity. Depending on the formulation, certain biopolymer-based packaging may present good barrier properties, antimicrobial and antioxidant activities Thus, polysaccharides and proteins can be combined to form diverse composite films with improved mechanical and biological behaviors, making them suitable for packaging of different food 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 Chitosan–Pullulan Composite Edible Coating Functionalized with Pomegranate Peel Extract on the Shelf Life of Mango (Mangifera indica)

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

Potentials of polysaccharides, lipids and proteins in biodegradable food packaging applications

Bio-based packaging materials are gaining importance due to their biodegradability, sustainability and environmental friendliness. To control the food quality and improve the food safety standards, proteins polysaccharide and lipid-based packaging films are enriched with bioactive and functional substances. However, poor permeability and mechanical characteristics are the challenging areas in their commercialization. Scientists and researchers are using a combination of techniques i.e. hydrogels, crosslinking, etc. to improve the intermolecular forces between different components of the film formulation to counter these challenges More recently, biodegradable packaging materials, sometimes edible, are also used for the delivery of functional ingredients which reveals their potential for drug delivery to counter the nutrient deficiency problems. This study highlights the potentials of bio-based materials i.e. proteins, polysaccharides, lipids, etc. to develop biodegradable packaging materials. It also explores the additives used to improve the physicochemical and mechanical properties of biodegradable packaging materials. Furthermore, it highlights the novel trends in biodegradable packaging from a food safety and quality point of view.

Extending Shelf-Life and Quality of Minimally Processed Golden Delicious Apples with Three Bioactive Coatings Combined with Cinnamon Essential Oil

The application of coatings with essential oils for food preservation is an alternative way to keep minimally processed apple slices fresh, nutritious, safe, sensory palatable, and accessible for consumers. In the present study, the effect of three bioactive coatings on quality variables of minimally processed Golden Delicious apple slices for 25-days at 4 °C was evaluated. The coatings were CT1-chitosan-based, CT2-guar gum-based, and CT3-composite guar gum-starch-based; all three coatings contained cinnamon essential oil and were compared with UCT0-uncoated apple slices. The quality variables evaluated were weight-loss, firmness, browning index, total phenolic content, total soluble solids, titratable acidity, respiration rate, microbial analysis, and sensory evaluation. All coatings improved the preservation and sensorial quality variables of Golden Delicious apples; however, although the CT1-chitosan-based coating was capable of extending the shelf-life of minimally processed apple, it demonstrated less sensorially favorable scores for flavor, odor, and overall acceptance attributes.

Euphorbia antisyphilitica Zucc: A Source of Phytochemicals with Potential Applications in Industry

Euphorbia antisyphilitica Zucc, better known as the candelilla plant, is one of the 10 non-timber forest products of greatest economic importance in the desert and semi-desert regions of Mexico. Moreover, it is a potential source of some functional phytochemicals such as polyphenolic compounds, wax and fiber, with potential applications in food, cosmetic and pharmaceutical industries. Thus, this review aims to describe these phytochemicals and their functional properties as antimicrobial, antioxidant, reinforcing and barrier agents. In addition, a suitable valorization of the candelilla plant and its byproducts is mandatory in order to avoid negative effects on the environment. This review provides, for the first time, an overview of the alternative methodologies for improving candelilla plant production, pointing out some of the agricultural aspects of the cultivation of this plant.

Candelilla Wax Edible Coating with Flourensia cernua Bioactives to Prolong the Quality of Tomato Fruits

The improvement of the postharvest quality of tomato fruits was evaluated using an edible coating functionalized with an Flourensia cernua extract evaluating the antifungal, structural, barrier, and optical properties. The formulation and evaluation of an edible coating and its application on tomato was evaluated using a response surface methodology to determine the ideal concentrations of candelilla wax, whey protein, and glycerol. Edible films showed good barrier properties, with water vapor permeability varying from 0.435–0.404 g mm/m² day kPa. The addition o F. cernua extract showed significant improvement in the transparency of films. The edible coating applied to tomato reduced weight and firmness loss. The sensory evaluation proved that the product obtained is acceptable for consumers. The edible coating added with F. cernua extract was the most effective in inhibiting the growth of pathogenic fungi and the visual appearance at the end of storage confirmed the beneficial effect of the edible coating.

Development of biodegradable films based on purple yam starch/chitosan for food application

One of the most critical challenges for the food packaging industry to overcome is the development of biodegradable coatings from renewable sources. In this work, purple yam starch (PYS), chitosan (CS), and glycerol were blended to obtain biodegradable films for characterization as intended food coatings. The films had a homogeneous surface, and the amount of CS highly influenced the film thickness. Infrared spectroscopy indicated hydrogen bond interactions between PYS and CS in the films. Thermogram data suggested that glycerol contributed to the thermal stability of the films, due to its greater interaction with CS than to the PYS. Finally, the application of a YS/CS film on apples for 4 weeks was able to preserve the fruit quality, as weight loss from the coated apple was significantly lower than the uncoated apple (p = 0.44, Dunnet's posthoc test). YS/CS films have great prospects in the food packaging industry as a new biodegradable coating.

Preparation, properties, and structural characterization of β-glucan/pullulan blend films

This study investigates the physico-mechanical and structural properties of β-glucan (BG)/pullulan (PUL) composite edible films successfully prepared with 0-0.3 g of BG. Results demonstrated that BG addition significantly increases the elongation at break (p < 0.05), tensile strength, and water dissolution time of the resulting films. The transparency of the 0.2PUL:0.1BG film and the oxygen barrier property of the 0.15PUL:0.15BG film decreased remarkably compared with those of the plain films (0.3PUL:0BG and 0PUL:0.3BG) and other composite films (p < 0.05). FTIR indicated hydrogen bonding interactions between PUL and BG molecules, and microstructural observations showed that aggregated BG is homogeneously dispersed in the PUL continuous matrix. Among the films tested, the thermal stability of the 0.15PUL:0.15BG film was the best. A PUL:BG mixing ratio of 0.15:0.15 is thus suggested to provide the best film properties. This research offers an alternative method to improve PUL-based edible films.

Categorical Nature of Consumer Price Estimations of Postharvest Bruised Apples

Postharvest fruits are susceptible to damage which eventually results in large product and financial losses. While abundant studies have been conducted to objectively index the severity of such damage, how consumers subjectively assess the severity of damaged apples has been understudied. Previous studies have indicated that consumers’ aesthetic devaluation of product quality is reflected in estimated price. Thus, the current online questionnaire study was conducted to examine the effect of objectively indexed severity of damage on consumers’ subjective price estimations. Four hundred thirty-nine consumers of apples were asked to estimate the market price for apples in photographic images of 1 or 3 “Orin” (“Golden Delicious” × “Indo”) apples at 9 levels of severity of damage. A 2 (1- and 3-piece) × 9 (severity of damage) within ANCOVA with reference price as a covariate indicated significant two-way interaction between the number of apples and severity of damage on estimated price. Consequently, the 1- and 3-piece conditions were examined separately. The results of both analyses indicate a categorical rather than quantitative, continuous reduction in estimated price.

Effect of growth conditions on β-glucosidase production using Flourensia cernua leaves in a solid-state fungal bioprocess

Flourensia cernua foliage was used in a solid-state fungal bioprocess to identify factors that could affect β-glucosidase production such as growth medium components and partial identification of molecules from the plant material. Under an exploratory experimental design, each variable had their distinctive result on conditions, which affects and could further improve β-glucosidase production. Under the experimental design, 1482 U/L of β-glucosidase were detected, which marks an improvement in production compared to levels obtained in a control treatment with an activity of 1092 U/L. It was shown that inoculum, water content and pH were the factors with the greater effect on β-glucosidase production. Polyphenolic content and cellulosic fiber in the form of raw fiber were measured to assess compound degradation of the plant material. Although fiber content was apparently unaffected, polyphenolic content decreased; β-glucosidase was produced by A. niger GH1. This behavior could be associated with fiber level and polyphenolic content because molecules of this type can be hydrolyzed by β-glucosidase. According to our results, F. cernua biomass can be used as a carbon source for β-glucosidase production in a short culture time.