...Food packaging is essential for food products to preserve and prevent them from containment. Today, the huge environmental problems associated with non-biodegradable food packaging materials have encouraged R & D sector to develop sustainable alternatives using renewable resources for future generations. The bio-based materials are interesting from environmental and sustainable points of view. In the past few decades, polysaccharides have been explored as renewable and functional materials for food packaging. This review summarizes the most promising functional polysaccharides frameworks for food packaging applications with future perspectives.
Keywords: Food, biopackaging, polysaccharides, edible films, functional materials.
Food packaging is essential for food products mainly to maintain the safety and quality of food products during storage and transportation to extend shelf-life of food products by preventing unfavorable conditions such as chemical contaminants, spoilage microbes, oxygen, light etc. . Food packaging technologies have been progressed as a response to the continuous changes in current consumer demands and market trends. Microbial contamination on the food products occurs primarily at the surface, due to post-processing handling. So, attempts have been made to improve safety and to delay spoilage using antimicrobial sprays. However, direct surface application of antimicrobial substances onto foods has limited benefits because the active substances are neutralized on contact or diffuse rapidly. Additionally, incorporation of bactericidal or bacteriostatic agents into meat formulations may result in partial inactivation of the active substances by-product constituents and is therefore expected to have an only limited effect on the surface microflora .
The plastic waste management is started by European Commision in the 1980s. Directive 85/339/EEC set rules on the production, marketing, use, recycling and refilling of containers of liquids for human consumption and on the disposal of used containers. To harmonize national measures concerning the management of packaging and packaging wastes to prevent or reduce its impact on the environment Directive 94/62/EC was adopted . In the present scenario of environmental safety and eco-preservation, the packaging and the food industries have reduced the amount of chemical based food packaging materials as they are associated with negative responses such as toxicity, non-degradability, incompatibility etc. [1-4]. To overcome the situation, consumer initiated the use of bioderived food packaging materials as an alternative to materials produced from non-renewable resources. Consequently, biopolymers have been used as low-cost functional materials to develop novel food packaging materials [4-7]. In order to perform active packaging functions, the material used should be satisfactory to the shelf life and quality of food products. The general properties required for novel food packaging materials are physical properties and bio-chemical properties (Fig. 1). In this regard, the food package should hinder gain or loss of moisture, prevent microbial contamination and act as a barrier against the permeation of carbon dioxide, water vapor, oxygen, and other volatile compounds along with the basic physical properties such as mechanical, optical and thermal. Among the biomaterials studied to develop biodegradable packaging films and coatings, polysaccharides such as chitosan, starch, cellulose, alginates etc [Fig. 2]. possess good barrier properties against the transport of gases such as oxygen and carbon dioxide. Polysaccharide-based materials are found to have excellent active functional properties and recognized as eco-safe materials. This chapter overviews current trends and applications of biodegradable polysaccharides as food packaging materials.
Fig. 1. General properties/characteristics required for novel food packaging materials
Fig. 2. Schematic representation of various functional polysaccharides
2. Functional Polysaccharides as Food Biopackaging Materials
Polysaccharides, chemically complex carbohydrates constituted by glycosidic bonds are abundantly found in nature and can be isolated from plants (cellulose, starch), animals (chitin and chitosan), microorganisms (alginates) etc. Polysaccharides and their derivatives exhibit various functional properties and therefore used in several industries, such as food, medical, pharmaceutical etc [3-7].
2.1 Plant derived Polysaccharides
Cellulose is one of the most abundant biopolymers on earth, occurring in plant-based materials such as wood, cotton, hemp etc. serving as the dominant reinforcing phase in plant structures. As a consequence of its chemical structure, it is highly crystalline, fibrous, and insoluble. In recent years, it is one of the most plentiful renewable resources in food packaging due to its edible filmï¿½ï¿½ï¿½s remarked properties including good barriers to oxygen, aroma and oil transfer similar to other hydrophilic films . Several water-soluble, composite coatings are made commercially from cellulose, carboxymethylcellulose with sucrose-fatty acid esters. Derivatives of cellulose, such as methylcellulose and hydroxypropyl methylcellulose, form strong and flexible water-soluble films. The barrier and mechanical properties of cellulose-based edible films have been reported in the literature, with these films also lower in water vapor permeability compared to other hydrophilic edible films .
Currently, a large number of companies are suppliers of cellulose-based commercial films and membranes. Innovia Films (Wigton, UK) presents two different products based on cellulose, Cellophaneï¿½ï¿½ï¿½ and NatureFlexï¿½ï¿½ï¿½, which are biodegradable and compostable, both sold worldwide for food packaging applications (Pre-made bags, tapes, box overwrap, bunch wrap, among others). Weifang Henglian Films CO. LTD (Weifang, China) provides food grade cellulose films with different sizes adapted for specific products [6,10].
Consequently, bio-nanocomposites/nanostructures open a clean opportunity for the use of new, high performance, light-weight green nanocomposite materials making them replacing conventional non-biodegradable petroleum-based plastic packaging materials . Rampazzo et al. investigated cellulose nanocrystals from lignocellulosic raw Materials, for oxygen barrier coatings on food packaging films and found that the gas barrier properties of the coating produced with CNCs obtained from kraft pulp were very promising, providing oxygen and carbon dioxide permeability values hundreds of times lower than those of equal thickness in comparison with common barrier synthetic polymers, over a broad range of temperatures . In addition, microcrystalline cellulose which comprises one of the most abundant biomass resources, has been regarded as an eco-safe and reliable food additive because it has the same ingredients as the cellulose in people's daily intake. In a recent study, it is concluded that gelatin microcrystalline cellulose-based film observed as safe, stable, eco-friendly and biorefractory material. The incorporation of a cellulosic cross-linker to gelatin-based films was an ideal choice with respect to developing a packaging for the food industry .
Starch, composed of repeating 1,4-ï¿½ï¿½-D glucopyranosyl units: amylose and amylopectin is the most abundant reserve polysaccharide found in plants and possesses non-toxicity, biodegradable nature. The amylose is almost linear, in which the repeating units are linked by ï¿½ï¿½ (1ï¿½ï¿½ï¿½4) linkages; the amylopectin has ï¿½ï¿½ (1ï¿½ï¿½ï¿½4)-linked backbone and ca. 5% of ï¿½ï¿½ (1ï¿½ï¿½ï¿½6)-linked branches. In general, it can be extracted from cereals (rice, corn), from tubers (potato, tapioca), from grains (amaranth) or even from nuts (cashew), but the main commercial sources of starch are corn, potato and tapioca .
The producers and traders of polymeric films based on starch include Novamont (Novara, Italy), which commercializes Mater-Biï¿½ï¿½, a biodegradable and compostable bioplastic commercialized in granular form that can be processed using the most common transformation techniques . Similarly, Eco-Go (Bangkok, Thailand) manufactured the finished packaging products from cassava and corn starch and distributed in the form of bowls, food containers, food trays etc. . In addition, high barrier multilayer sheets for packaging goods from corn starch and polyethylene and polypropylene have been produced by Plantic Technologies Limited (Altona, Australia) under the trade name PlanticTM .
Furthermore, Romani et al. described active and sustainable materials from rice starch, fish protein, and oregano essential oil for food packaging. In this study, it is concluded that the use of rice starch and fish protein to form sustainable blends represents an interesting alternative for the production of active packaging and for the development of eco-friendly technologies . Another study was focused on the preparation of edible cassava starch films carrying rosemary antioxidant extracts for potential use as active food packaging by Piï¿½ï¿½eros-Hernandez et al. . Recently, polylactic acid and starch-based edible films have been extensively studied as potential replacements for non-degradable petrochemical polymers on the basis of their availability, adequate food contact properties, and competitive cost. Nevertheless, both polymers exhibit some drawbacks for packaging uses and need to be adapted to the food packaging requirements. Particularly, starch is very water sensitive and its film properties are heavily dependent on the presence of moisture content, exhibiting relatively low mechanical resistance. The polylactic acid and starch combination was found effective to obtain biodegradable food packaging materials that represent good alternative means to reduce plastic waste . Consequently, novel biodegradable starch/clay nanocomposite films were investigated for food packaging applications by Avella et al. . In this study, the good intercalation of the polymeric phase into clay interlayer galleries, together with an increase of mechanical parameters, such as modulus and tensile strength in case of starch/clay nanomaterials was observed. In a more recent study, Meira et al. reported a novel active packaging material based on starch-halloysite nanocomposites incorporating antimicrobial peptides and concluded that starch-halloysite nanocomposites incorporating antimicrobial peptides have considerable potential to be a successful food packaging material. .
Galactomannans are neutral polysaccharides obtained from the endosperm of dicotyledonous seeds of several legume plants, consisting of a mannose backbone with galactose side chain groups, in particular, a (1-4)- ï¿½ï¿½-D-mannopyranose backbone with branch points from their 6-positions linked to ï¿½ï¿½-D-galactose, i.e. 1-6-linked ï¿½ï¿½-D-galactopyranose). Most common usage is reported in the food industry, mainly as stabilizers, thickeners, and emulsion stabilizers as well as for the production of edible membranes and coatings. In partially purified form, they find widespread applications as thickening as well as gelling (in the presence of other polysaccharides) agents in food industry. Also, partially degraded guar galactomannan is used as a novel dietary fibre component in food. Several legume species have a different number of mannose-to-galactose ratios [22,23]:
ï¿½ï¿½ï¿½ fenugreek gum, mannose:galactose ~1:1
ï¿½ï¿½ï¿½ guar gum, mannose:galactose ~2:1
ï¿½ï¿½ï¿½ tara gum, mannose:galactose ~3:1
ï¿½ï¿½ï¿½ locust bean gum or carob gum, mannose:galactose ~4:1
ï¿½ï¿½ï¿½ cassia gum, mannose:galactose ~5:1
The great advantage of galactomannans is their ability to form very viscous solutions at relatively low concentrations that are only slightly affected by pH, ionic strength and heat processing type. The viscosity of Galactomannans tends to remain constant over a broad pH range (1-10.5), and chiefly due to their neutral character molecules. However, degradation may occur under highly acidic and alkaline conditions at high temperatures to a significant extent .
For commercial purposes, Altrafine GumsTM (Ahmedabad, India) export to about 90 countries of a wide range of different types of gums . Cargill (Minneapolis, MN, USA) offers various types of locust bean gum and guar gum flour or extracts under the trade name Viscogumï¿½ï¿½ï¿½ . Chemtotal (Chatswood, Australia) also produces and trades variable purified galactomannans (guar gum, locust bean gum, tara gum and cassia gum) . Cerqueira et al. published a comprehensive review to provide an insight on the relevant work that is being developed in the area of novel galactomannan-based biodegradable packaging materials and to explore the potential use of those alternative materials by the food industry. They concluded that galactomannans films/coatings possess good mechanical, barrier and rheological properties that may be used to improve the stability, safety, and quality of the food products . Similar results were obtained from another study of the same research group when they immobilized bioactive compounds in Cassia grandis galactomannan-based films . Galactomannans have been tested in apples to decrease the internal oxygen concentration, and sensory analyses revealed that the coated apples maintained consistent quality in firmness, crispness, and juiciness. Additionally, galactomannans based edible membranes have been applied to fruit and cheese products . In a similar study, coatings based on galactomannan, glycerol and corn oil have been applied in cheese, decreasing the transfer rates (water vapor and oxygen), weight loss and color change .
2.2 Animal derived Polysaccharides
2.2.1 Chitin and chitosan
Natural polymers being biodegradable nature, preferably considered for an assortment of value-added functionalities. The most abundant biopolymer, found in nature is cellulose, a polysaccharide. Chitin is the second most abundant polysaccharide in nature after cellulose and produced by a variety of exoskeletons of crustaceans and molluscs, insect cuticles and fungi. Chitin is usually converted to chitosan by deacetylation process, obtaining a more soluble material, chitosan in the aqueous acid medium. Crustacean members have decalcified cuticles that contain approximately 55-85% chitin. Chitin is secreted over the entire body of the animal by a single layer of cells of the epidermis, whereas the exocuticle does not contain chitin. The endocuticle is made of several chitin-containing layers, generally impregnated with mineral salts, such as carbonates and phosphates of calcium [31,32]. Chitin and chitosan based membranes are recognized as a renewable, non-toxic, biodegradable, biocompatible and biologically active (antiseptic, germicidal, anti-bacterial, fungicidal and anti-viral) polymer. Moreover, chitosan membranes are reported as being semipermeable to gases presenting low oxygen permeability which is essential for some food products preservation, and moderate water vapor barrier .
Chitin and chitosan have been utilized for renewable food packaging materials around the world. In this regard, GTC Bio Corporation (Qingdao, China) commercializes different grades of chitin as well as chitosan products . Norwegian Chitosan (Klï¿½ï¿½fta, Norway) trades chitin and chitosan under brand names NorLife and Kitoflokkï¿½ï¿½ï¿½, respectively, for several applications, including food and beverages . In addition, Primex (Siglufjordur, Iceland) commercializes ChitoClearï¿½ï¿½, chitosan products that intend to be based on the purest chitosan possible with potential application in food packaging . Villafane has shown in her work, the quality attributes of map packaged ready-to-eat baby carrots by using chitosan-based coatings, that chitosan films are effective in preserving some of the properties of carrots as well as in preserving them longer. Different treatments have been described in order to prevent or slow down the preserving related problems and concluded that the edible coating based on chitosan benefits include stabilizing the product and thus extending foodï¿½ï¿½ï¿½s shelf life . van der Broek et al. reviews of detail and described the latest developments of chitosan films and blends as packaging material, recently . Thus, chitosan coatings were proved to be beneficial in maintaining a higher product quality during the storage period for increased shelf-life of food products.
2.3 Microorgaanism derived Polysaccharides
2.3.1 Polymaltotriose or Pullulan
Pullulan is one of the biopolymers that have gained much attention over recent years due to its peculiar characteristics. Pullulan, produced by fungi like Aureobasidium pullulans using a variety of feedstocks containing simple sugars, is a linear, water-soluble, biodegradable, non-toxic, tasteless and odorless, and neutral exopolysaccharide composed mainly of maltotriose units linked by ï¿½ï¿½ï¿½-1,6 glycosidic linkages. Its membranes started to be commercialized by Hayashibara in 1982 . Shandong Jinmei Biotechnology Co. Ltd. (Zhucheng, China) is an important producer of pullulan, which is commercialized in powder or capsules forms, with the wide applications like edible and oral dissolving membranes, coatings in soft candies, among others . In the area of the food industry, early applications of pullulan involved its use as a thickening, stabilizing, texturizing, and gelling agent, providing products with good sensory properties, extended shelf life, and easier processing . However, pullulan has a number of advantages, therefore, its high cost limited the use of pullulan and pullulan membranes in several applications . Another study encompassed the evaluation of pullulan as a suitable biopolymer for the development of oxygen barrier coatings to be applied on poly(ethylene terephthalate), especially for food packaging applications . In this study, the oxygen barrier properties of the organic phase (pullulan) even at high relative humidity values, an inorganic phase (silica), obtained through in situ polymerization, was utilized to obtain hybrid coatings via the sol-gel technique. Using silica the overall cost was found lower.
FucoPol is biodegradable, anionic and water-soluble heteropolysaccharide, high molecular weight exopolysaccharide, mainly produced by the bacteria Enterobacter sp. A47 using glycerol byproduct from biodiesel industry as a carbon source. The unit composition of FucoPol is fucose (36%ï¿½ï¿½ï¿½38% mol), galactose (22%ï¿½ï¿½ï¿½24% mol), glucose (27%ï¿½ï¿½ï¿½33% mol), glucuronic acid (9%ï¿½ï¿½ï¿½10% mol) and acyl groups (acetate, succinate and pyruvate), which account for 12ï¿½ï¿½ï¿½18 wt % of dry weight [6,42]. Ferreira et al. investigated the FucoPol biodegradable films produced from the bacteria Enterobacter sp. and characterized in terms of optical, mechanical and barrier properties . As a result, the films are transparent, but have a brown shade that caused color changes noticeable to the Human eye when placed over a colored surface, hydrophilic and soluble in water, which makes them poor barriers to water vapor. By the contrary, FucoPol films sowed good barrier properties to gases (oxygen and carbon dioxide). The mechanical tests revealed a ductile film, with high elongation at break and a low tension at break and elastic modulus. Consequently, FucoPol and chitosan bilayer membranes have reported with enhanced properties when compared to FucoPol stand-alone membranes. They exhibited better gas barrier properties, lower solubility in liquid water, and better mechanical properties. The improved properties support the use of bilayer films (FucoPol/Chitosan) with low moisture content products and can be used as functional food packaging material .
2.3.3 Xanthan gum
In 1963 xanthan gum was discovered at the Northern Regional Research Laboratories (NRRL) Peoria, IL, USA. It was the second microbial polysaccharide commercialized. It is an exopolysaccharide consists of repeated pentasaccharide units composed of glucose, mannose and glucuronic acid (ratio = 2:2:1) and pyruvate and acetyl as substituent groups. Xanthan gum is water-soluble and non-toxic and isolated from Xanthomonas campestris using glucose and sucrose as a sole carbon source [5,6]. The rheological properties of xanthan solutions are quite stable in a wide range of pH, ionic strength and temperature values .
Xanthan gum possesses active properties and therefore has been used in a wide variety of industrial applications, such as food, cosmetic, pharmaceutical, textile, petroleum production etc. In the food industry, it is mainly used as an additive in the forms of suspending or thickening agent [5,46]. The major producers/manufacturers of xanthan gum with different purity grades are included Merck (Kenilworth, NJ, USA), Sanofi-Elf (Gentilly, France), CP Kelco (Atlanta, GA, USA), Danisco (Copenhagen, Denmark), and Jungbunzlauer (Basel, Switzerland) .
2.3.4 Gellan gum
Gellan gum is an anionic water-soluble exopolysaccharide, produced by Sphingomonas elodea, Auromonas elodea/Pseudomonas elodea. It is a linear heteropolysaccharide having high molecular weight with a tetrasaccharide repeating sequence composed of two residues of ï¿½ï¿½ï¿½-D-glucose, one of ï¿½ï¿½ï¿½-D-glucuronic acid and one of ï¿½ï¿½ï¿½-L-rhamnose with approximate composition: glucose (60%), rhamnose (20%) and glucuronic acid (20%) . In its original form (high acyl gellan), forms soft, elastic, non-brittle, thermo-reversible gels, and low acyl gellan tends to form firm, non-elastic brittle and thermostable gels and gum has two acyl substituents like acetate and glycerate. Low acyl gellan gum is obtained with the removal of acyl groups from high acyl gellan form. [6,47].
In the food industry, gellan gum is usually used as a stabilizer, thickening agent, and gelling agent. It is successfully applied to generate membranes and coatings for the food industry, such as breading and batters for cheese, chicken, fish, vegetables, and potatoes. In a recent study, gellan gum was combined with purple sweet potato (PSP) to obtain stable gellan gum/PSP composite films that exhibited reduced hydrophilicity, swelling property, and water vapor transmission rates as compared to the films prepared from gellan gum alone . As a result, gellan gum/PSP composite film may have potential as an active and intelligent packaging material showing enhanced antioxidant, water-resistant and mechanical properties, and may be served as an easy-to-use indicator system to detect the spoilage of protein-rich foods caused by the growth of bacteria.
Curdlan, colorless powder, is composed of a linear homopolymer of D-glucose with ï¿½ï¿½-1,3 linkages. It is a water-insoluble bacterial glucan polysaccharide and isolated from non-pathogenic strains of Alcaligenes faecalis var. myxogenes and Agrobacterium sp. It has heat-gelling and water-binding functionalities that are very important to the food industry. Wu et al. described a series of novel edible blend films based on konjac glucomannan and curdlan, prepared by a solvent-casting technique with different blending ratios of the two polymers . In this study, the electron tensile testing analysis indicated that the blend film KC7 showed the maximum tensile strength and the blend films displayed excellent moisture barrier properties, which had a potential application in the food field.
2.4 Algae derived Polysaccharides
2.4.1 Alginic acid or Alginate
Alginic acid or commonly known as alginate is a linear polysaccharide that is abundant in nature and is synthesized by brown algae, the member of Phaeophyceae (Laminaria, Macrocystis and Ascophyllum sp.) and some soil bacteria. It has been extensively investigated and used for many biomedical applications. It has an anionic character and is water-soluble, consists of 1-4-linked ï¿½ï¿½ï¿½-D-mannuronate (M blocks) and ï¿½ï¿½-L-guluronate (G blocks), as well as segments of alternating mannuronic and glucuronic acids (MG blocks) [6,50]. Alginate shows appealing film-forming capabilities for food such as thickening, stabilizing, suspending, gel-producing because of their non-toxicity, biodegradability, biocompatibility and low cost . Cargill (Minneapolis, MN, USA), FMC (Philadelphia, PA, USA) and DuPont (Danisco, Copenhagen, Denmark) are the market producers of alginates with variable grades [3,6].
In a recent study, Polyelectrolyte structured antimicrobial food packaging materials were prepared by using starch, cationic starch and sodium alginate . In this study, obtained results prove that produced food packaging materials have good thermal, antimicrobial and surface properties, and they can be used as food packaging material in many industries. Similarly, Brandelero et al. performed an investigation aimed to evaluate the efficiency of biodegradable films comprising starch/polyvinyl alcohol/alginate with the addition of 0 or 0.5% of essential oil of copaiba or lemongrass compared to poly-vinyl chloride (PVC) films in the storage of minimally processed lettuce . Multivariate analysis, as a result, showed that the lettuce lost quality after two days of storage in PVC films, representing a different result from the other treatments and lettuce stored in biodegradable films for two and four days showed a greater similarity with newly harvested lettuce (time zero). Similar characteristics were observed the films with or without the addition of essential oil. Therefore, alginate based biodegradable films were considered a viable source for the storage of minimally processed lettuce.
Carrageenan is a naturally occurring linear, anionic, sulfated and hydrophilic polysaccharide which is extracted from red seaweeds, (members of Rhodophyceae family e.g., genera Eucheuma, Chondrus, Kappaphycus and Gigartina). Carrageenan is composed of ï¿½ï¿½-D-1,3 and ï¿½ï¿½-D-1,4 galactose residues that are 40% sulfated of the total weight. Carrageenan is recognized as a food-grade additive. It has been widely used as emulsifier and stabilizer in flavored milk, dairy products, pet food and infant formulas . So far, carrageenan-based edible membranes and films/coatings have been reported as food encapsulating matrices. A number of companies are being manufactured and supplied carrageenan extracts worldwide. The largest and the most experienced producer is FMC (Philadelphia, PA, USA) that export under the brand names of Gelcarinï¿½ï¿½ and Viscarinï¿½ï¿½ . Apart FMC other key companies in the carrageenan market are Danisco (Copenhagen, Denmark), Ceamsa (Porriï¿½ï¿½o, Spain), CP Kelco (Atlanta, GA, USA) and Quest International (Naarden, The Netherlands) . Moreover, Cha et al. described the potential of application of grape fruit seed extract with and without EDTA, especially in inhibition of gram-negative bacteria contaminating foods for biodegradable films based on Na-alginate- and k-carrageenan . In this study, antimicrobial efficacy of these films against L. innocua, E. coli, S. aureus, Salmonella enteridis and M. luteus was tested. As a result, Na-alginate-based films produced a larger inhibition zone than k-carrageenan-based films/coatings. Hybrid k-carrageenan-based formulations for edible film preparation have been reported by Larotonda et al. . Films forming solutions produced with hybrid carrageenan in this investigation showed rheological properties comparable to commercial k-carrageenan-based solutions. Further, films formulated with hybrid carrageenan show significantly enhanced UV barrier, oxygen barrier, and hydrophobic properties. Thus, hybrid carrageenan proved to be a promising material for the production of edible coatings and biodegradable films and a good alternative to k-carrageenan for such application.
Although, the synthetic origin films/coatings as food packaging materials found to have negative responses such as toxicity, non-degradability, and incompatibility with the environment [5,32,36]. Thus, consumer demands and requirements by regulatory agencies to use more environmentally-friendly and less polluting packages have directed researchers to look at packaging materials that are derived from natural or made from renewable resources to replace, at least some, of the synthetic polymers. Also, it is quite difficult to draw a strict line where the technical function of an additive is solely its antimicrobial effect on the packaging without an impact on the food itself. Most of the materials used in antimicrobial packaging systems only act as a reservoir for the active substance and the target effect is on the food in contact with the package. So, this is clearly in conflict with the Plastics Directives of the European Commission . Therefore, new functional packaging materials are continually being developed. Many of them exploit natural agents to control common food-borne pathogenic microorganisms. Current trends suggest that, in due course, packaging will generally incorporate antimicrobial agents, and the sealing systems will continue to improve. Sustainability requires a fine balance between environmental, economic and social concerns. In the present time, biopolymers from renewable resources have been explored extensively due to their unique characteristics such as non-toxic, biodegradable and compatible with the environment [1-5,50]. Biopolymers can be considered sustainable in terms of material supply, water, and energy use and waste product generation. Moreover, the product viability, human resources, and technology development should also be pondered from a point of view of sustainability [2,6,51]. In addition, natural polysaccharides based films/coatings possess remarked properties to be eco-safe food packaging materials such as hydrophilicity, permeability, biocompatibility, and active functionalities. However, the biodegradable and biocompostable materials are, many times, more expensive and more difficult to process, a fact that further increases their cost compared to synthetic substances. Owing to the safety as well as environmental compatibility, the cost is no matter and this circumstance is changing gradually, by using a low-cost material collection, processing, and novel conversion technologies to a significant extent.
4. Conclusion and Future Outlook
Active packaging based on the biopolymeric system is an innovative food packaging concept and has been a popular area among the scientific community and due to its potential to provide food quality and safety measures. During the past few decades, researchers on environmentally safe alternatives from flora and fauna have been explored devoted to bioactive renewable materials and their potent applications in food packaging applications. In this regard, the utilization of biopolymers/biomaterials is being under considerations in order to get several active functional properties as food packaging materials. Polysaccharide-based membranes for food packaging applications have been described in this chapter. Polysaccharides can be extracted from different renewable sources such as plants, animals, algae, and microorganisms which possess strong functional properties and may replace the conventional synthetic and non-biodegradable ones as food packaging materials. Taking into consideration that the public, as a whole is already conscious to the environmental safety, it can be recommended for future dimension to the more developed food packaging materials, emphasized on greener and safety features associated with the competitive products with brilliant performance and low-price.
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