Edible Pouch Packaging for Food Applications—A Review

Abstract

Current food packaging, primarily made of non-biodegradable plastics, significantly contributes to environmental pollution. New packaging systems for food applications from biopolymers and/or with multifunctional properties are being developed as substitutes for synthetic polymers. The increasing concern over the environmental effects of packaging waste is driving a transition toward renewable packaging materials. Edible films and coatings play a vital role in maintaining food quality by preventing the loss of aroma, flavour, and important components, while also extending shelf life. Biopolymers, including polysaccharides, proteins, and lipids, are gaining attention as the future of packaging due to the environmental issues linked to petrochemical-based plastics. Modern packaging should not only protect products but also be biodegradable, recyclable, and have a minimal ecological impact. This review comprehensively summarises edible packaging in the form of single-use, fast-dissolving pouches for food applications as a circular approach and a sustainable solution in food technology. Innovations have resulted in the development of a unique packaging solution made from renewable sources. This packaging utilises plant and animal by-products to create edible films and pouches that are easy to seal. Edible packaging is emerging as a sustainable alternative, designed to simplify food packaging while minimising waste. Fast-dissolving scalable packaging, particularly edible films that dissolve in water, is used for individual servings of dry foods and instant beverages. This includes items like breakfast cereals, instant coffee or tea, and various powdered products. Additionally, there is an innovative approach to single-use packaging for oils and powders, leveraging the convenience and efficiency of these fast-dissolving films. Edible pouch packaging, made from safe and edible materials, provides a biodegradable option that decomposes naturally, thereby reducing pollution and the need for disposal.

1. Introduction

Food packaging is essential for food products and plays a crucial role in food manufacturing, significantly contributing to the maintenance of food quality [1,2]. For centuries, ancient societies relied on gathering food from nature, often without much thought to storage. In ancient times, people utilised plant leaves to cover or hold food, marking the beginning of the evolution of packaging. Until the 1800 s, packaging materials primarily consisted of natural items such as leaves, gourds, and shells, which served as containers. People also crafted baskets from grasses, wood, and bamboo. Additionally, primitive materials like pottery, paper, and glass were formed into containers for holding food. Significant changes in food packaging did not occur until about 150 years ago, leading to the modern forms we use today [3]. In general, food packaging has three main functions: protecting, preserving, and promoting products. Its primary role is safeguarding food from external harm while showcasing ingredient details to attract consumers [4,5]. Secondary functions, like convenience and security features, are also gaining importance in packaging. The overarching aim is to package and present food economically, meeting industry standards while aligning with consumer expectations, needs, and preferences. This must be achieved while ensuring food safety and minimising environmental impact. New packaging materials made from natural ingredients are being developed, along with improvements and modifications to conventional packaging, such as the use of active coatings [6,7].

Packaging is crucial in safeguarding food quality by shielding against physical, chemical, and environmental factors [8,9]. Techniques like modified atmosphere packaging (MAP), vacuum packaging, aseptic packaging, and active packaging are used to extend shelf life and maintain food freshness [10]. Modified atmosphere packaging alters the air inside food packages by using a gas blend such as nitrogen, carbon dioxide, and oxygen before sealing. This method is typically used for fresh or minimally processed foods that are still undergoing respiration, including meat, cheese, and plant-based products [11]. Vacuum packaging is a common method used to preserve food by sealing it in a low-oxygen material after removing the air. deterioration. This method significantly decreases oxygen levels, helping preserve food quality by minimising reactions that cause deterioration [12]. Moreover, aseptic packaging involves placing sterile products into sterile packaging materials within a clean environment. This ensures tight seals to prevent any contamination [13].

Environment-friendly renewable materials are essential for various functional packaging solutions for different food products, including perishable fresh produce [14]. Edible packaging such as films and coatings, derived from food ingredients or agricultural and industrial food production waste, shows an additional value by repurposing by-products or leftovers [1,15]. This type of packaging addresses the global demand for natural food packaging solutions and economical materials for various applications [16]. Biopolymers, including polysaccharides such as cellulose, starch, chitosan, pectins, gums, alginates, and proteins sourced from animals and plants, are the most popular for the preparation of edible materials, forming. While this technology does not entirely replace traditional packaging, mostly due to the limitations in use, it may reduce cost and bulk compared to conventional materials [17]. Moreover, these packaging materials enhance food preservation as a barrier against gases and moisture [18]. They may also regulate the release of food additives and nutrients into packaged food [19]. A shift in society towards ecological awareness, environmental preservation, economic factors, and health consciousness is driving the growth of biopolymer-based edible packaging [20]. However, the circular approach and the requirements related to this approach are being implemented in many countries to minimise the negative impact on the environment [21]. Using naturally derived, biodegradable materials helps reduce our dependence on synthetic packaging, which in turn decreases waste generation and minimises the harmful impact of microplastics from single-use plastics. This transition supports broader sustainability goals by promoting renewable and eco-friendly packaging alternatives, significantly lowering the environmental impact of our packaging practices [14]. Advancements in edible film technology have expanded the achievable properties while also aiming to lower production costs. These properties are influenced by the materials used and the processing conditions [22]. Material concentration, plasticiser type, solvent composition, film thickness, pH, and temperature significantly impact film properties, including the mechanical resistance, barrier property against gases or light, thermal stability and sensitivity to moisture. These variables allow for the customisation of specific characteristics, enhancing desired functionalities and improving the effectiveness of edible films for various applications in the food industry [23]. One of the most important aspects of edible packaging is its ability to seal with heat, which has not been extensively studied in recent scientific research. There has been a growing interest in the development of fast-dissolving, scalable packaging in recent years. This paper aims to characterise edible films used as packaging materials in the form of pouches that dissolve quickly upon contact with water. These films show promising applications, particularly for individually portioned dry ingredients, such as powdered foods or instant beverages. They are also suitable for oils and other products with low to intermediate water activity, including cereals, baked goods, dried fruits, vegetables, and nuts.

2. Biodegradable Films, Edible Coatings and Sachets

Bio-based food packaging as an innovation can enhance user convenience and reduce packaging waste in various dry food and beverage industries [14]. This type of packaging system can be edible in different forms, as presented in Figure 1, including film, coating, sachet, or wrap. Biodegradable films present a promising alternative to traditional plastic packaging. However, their full implementation requires significant effort. These films are designed to break down naturally, which reduces their environmental impact compared to non-biodegradable materials. They also provide a protective barrier for food items while minimising pollution concerns [24]. Edible coatings are formulated from edible materials and applied directly to food items’ surfaces. They serve as a protective layer, preserving freshness and extending shelf life. Edible coatings can improve the appearance and attractiveness of food products [15,25]. Sachets within active packaging often contain specialised materials or substances that help regulate the environment around the food. They may absorb excess moisture, oxygen, or odours or even release compounds like antimicrobial agents or antioxidants to maintain food quality [26]. These innovative packaging methods aim to mitigate some environmental and waste issues associated with traditional packaging materials. By providing functions beyond simple containment, they help extend the shelf life of food, minimise spoilage, and preserve the sensory qualities and safety of food products.

Edible coatings are composed of compounds that are deemed safe for consumption and are classified as Generally Recognized As Safe (GRAS). These compounds have undergone thorough evaluation and received approval from regulatory bodies such as the FDA or EFSA for use in food applications. Additionally, the production of these coatings adheres to Good Manufacturing Practices (GMP) established for food products. These practices ensure that the coatings are prepared, handled, and processed under controlled and hygienic conditions, meeting quality standards to ensure the safety and quality of the final product. This adherence to safety regulations and quality standards assures consumers that edible coatings are developed with their health and safety in mind and comply with regulatory guidelines. Janjarasskul et al. [27] developed scalable, edible films made from fast-dissolving whey protein isolate for packaging premeasured dry foods. These films are completely water-soluble, visually transparent, glossy, and release their contents upon contact with water. Liu et al. [28] studied heat-sealable soybean polysaccharide and gelatin blend films designed for use as edible food packaging materials for instant coffee and coconut powder pouches. More examples of edible pouches for food products are presented in

Table 1. The examples of edible pouches for food applications.

Pouch Main Components	Food Application	Effect	References
Corn zein	Cheese	Maintain the cheese qualities proved by the physical and microbiological changes over 28 days at 5 °C	[29]
Corn zein and soy protein isolate	Olive oil	Reducing the increase in peroxide values during 120 days of storage (enhanced the oxidative stability)	[30]
Soybean polysaccharide and pork gelatin	Instant coffee, coconut powder	Dissolving in water in less than 30 s; no tests on the product	[28]
Whey protein isolate	Instant coffee; salad dressing	Dissolving (completely or partially) in hot water (90 °C); no tests on the product	[27]
Corn starch, low methoxyl pectin and bovine gelatin and carboxymethylcellulose	Instant coffee	Preservation of quality characteristics	[26]
Orange peels, calcium salts and citric acid	Herbs	No tests on the product	[33]
Gelatin and chitosan	Shrimp oil	Enhanced the oxidative stability	[34]
Fish gelatin	Chicken skin oil	Enhanced the oxidative stability	[35]

. These studies indicate that scalable biopolymer-based single-use packaging is promising for reducing reliance on petroleum-based materials. Additionally, biopolymer-based single-use packaging made from corn zein has been explored to enhance the shelf life of sliced cheese [29], and, when combined with soy protein isolate, may play a role as packaging for olive oil [30]. Various types of water-soluble pouches for oil protection have been studied by other researchers in the past [31,32].

Biodegradable films, edible coatings, and sachets have gained significant attention in active packaging. Their increasing importance is due to their potential to transform food preservation and promote sustainability [14,17]. Edible film in food packaging is a thin layer that can either be pre-formed and applied to the surface of food or created directly on the food by drying. This film serves as a protective barrier, shielding the food from external factors such as moisture, air, and contaminants. It can be used on various food items to extend shelf life, preserve freshness, and improve overall quality [22]. The casting method is commonly employed to create edible films. It entails preparing a solution containing film-forming components, which is then evenly spread across a smooth surface and dried. As the solution dries, it transforms into a thin, flexible layer that can be utilised for preserving and packaging food products. This technique is preferred for producing uniform films with regulated thickness and composition, making it ideal for a range of food applications.

Polysaccharides, lipids, and proteins are the main materials used to create edible films and coatings in the food industry (Figure 2). Each class offers distinct properties suitable for various purposes. Polysaccharides include cellulose, starch, alginate, chitosan, and gums. They possess properties such as biodegradability, moisture resistance, and gas barrier capabilities. Lipids like waxes and fatty acids provide water resistance and moisture control for specific food items [36]. Proteins like gelatin, soy, whey, and gluten contribute mechanical strength and flexibility to films [17].

Protein-based edible packaging exhibit similar mechanical and barrier properties to polysaccharide-based ones. The unique structural characteristics of proteins enable stronger intermolecular interactions, resulting in films that offer increased strength, flexibility, and better resistance against moisture and gases. Chen et al. [37] highlighted that protein-based materials have high functional properties, making them preferable for various food applications requiring robust barriers and enhanced mechanical strength.

Lipid coatings often offer excellent moisture barriers, yet they come with drawbacks. Some disadvantages associated with lipid coatings include undesirable sensory characteristics and brittle or non-cohesive films. While lipid coatings excel in providing moisture barriers and can be beneficial for specific food items, the sensory changes they induce and the potential issues with film properties must be considered [38]. The choice of material for films or coatings depends on the specific characteristics of the food product and its intended purpose, such as moisture control, gas barrier, preservation, or other functions. Selecting the right polymer is crucial because it influences the properties of the film and its compatibility with the food [5,39].

While highly permeable to oxygen and water vapour, the sachet technology demonstrates a unique capability: it absorbs residual oxygen in favourable humidity conditions, forming stable iron oxide. Absorber sachets are systems designed to eliminate undesirable compounds such as oxygen, ethylene, carbon dioxide, and excess water from the free space within packages or around food. This action helps prevent the rapid deterioration of food products [40]. The moisture controller sachet addresses the issue of excessive liquid water accumulation within plastic packaging caused by the transpiration of food products. This accumulation can create favourable conditions for the growth of fungi and bacteria. Moisture absorbers are used in various food items, including fruits, vegetables, cheese, meat, chips, peanuts, sweets, and spices.

Carbon dioxide-absorbing sachets are used specifically for food items such as freshly ground or roasted coffee, which produce significant amounts of carbon dioxide. It is crucial not to vacuum seal these products immediately after roasting because the generated carbon dioxide can accumulate within the package, potentially causing it to puff up or even break. Additionally, a high concentration of carbon dioxide in the package can effectively inhibit microbial growth in food products such as meat and poultry [41].

Sachets that absorb ethylene help regulate its concentration inside or around food packages. This regulation decreases metabolic activity, extending the shelf life of fresh fruits and vegetables [42]. Ethylene, a natural maturation hormone found in climacteric fruits, accelerates the respiration rate in these fruits. Using an ethylene-absorbing system becomes crucial in maintaining these fruits’ visual appearance and organoleptic quality. As a result, managing ethylene levels is crucial for prolonging the shelf life of fruits after harvest.

The packaging industry, particularly within the food and related sectors, is one of the most significant and rapidly growing commercial segments worldwide. The demand for packaging materials continues to surge, spurring substantial growth in this industry. According to the Fortune Business Insights Research Report, the global food packaging market was approximately $394 billion in 2018 and is expected to grow to around $606 billion by 2026, reflecting a compound annual growth rate (CAGR) of 5.6%. This robust growth trajectory underscores the significance of packaging solutions within various industries. Furthermore, there is ongoing and notable innovation within this sector to enhance packaging materials, sustainability, functionality, and overall efficiency to meet consumers’ and industries’ evolving needs and demands [43].

Consumer preferences are shifting towards eco-friendly food packaging due to growing concerns about packaging waste. Consumers increasingly desire safer, higher-quality, and more convenient food options that reflect sustainable practices. This trend has led to greater research and industry focus on creating sustainable, biodegradable, and edible packaging materials. These innovations aim to maintain the food safety and quality while addressing environmental concerns by minimising pollution and waste in packaging practices. The industry is evolving to meet the growing demand for environmentally friendly packaging solutions [44].

3. Different Aspects of Food Packaging

Unit food packaging is essential for preserving the quality and durability of food products. Recently, there has been a growing interest in discovering new, more sustainable, and environmentally friendly packaging materials [45]. A food packaging material’s primary properties are barrier properties and product protection against mechanical contamination from the external conditions. Barrier properties contribute to maintaining the product’s relevant quality during the shelf life. This mechanism limits the access of gases, such as oxygen and water vapour, to the packaged product, significantly slowing the rate of various biochemical transformations occurring in food. The packaging material should limit the permeability of gases and aromas and inhibit, among others, the fat oxidation process, which usually leads to maintaining the product’s natural nutritional and organoleptic properties. Edible coatings and biodegradable films have proven innovative and advantageous across various economic and environmental dimensions.

3.1. Social Impacts

Social aspects of food packaging include (1) Safety and Health: Edible coatings contribute to food safety by providing a protective layer that can reduce contamination risks. They can also enhance the sensory qualities of food, making it more appealing to consumers; (2) Consumer Acceptance: These technologies align with the growing consumer demand for natural and sustainable products. They offer an alternative to conventional plastic packaging, addressing concerns about environmental pollution.

Consumer health has raised concerns regarding certain synthetic antimicrobials used as food preservatives. One example is sulfites, a group of sulfur-based chemicals employed in food preservation. These substances have been associated with various negative effects on nutrition. Specifically, sulfites have been linked to anti-nutritional impacts, such as the degradation of thiamine, or vitamin B1, in food [46].

3.2. Environmental Impacts

The environmental impact of packaging can be considered a crucial aspect in terms of (1) Reduced Pollution: Biodegradable films reduce the environmental impact of traditional plastics by naturally breaking down, minimising pollution, and lowering the carbon footprint associated with packaging. (2) Resource Conservation: Both biodegradable films and edible coatings promote the use of renewable resources or materials that are more easily replenished, thus reducing dependence on non-renewable resources.

Overall, these technologies have the potential to positively influence the way products are packaged, consumed, and disposed of, aligning with societal demands for more sustainable and environmentally conscious practices. As they continue to develop and become more widespread, their benefits are likely to grow, making significant contributions to sustainability in the packaging industry [47].

3.3. Economic Impacts

The economic impact on the production of sustainable edible pouch packaging is in terms of (1) Reduced Waste and Costs: Biodegradable films break down naturally, reducing the accumulation of non-biodegradable waste. This can potentially lower waste management costs and contribute to cleaner environments. (2) Resource Efficiency: Edible coatings often utilise food-grade materials, sometimes by-products from food processing, which can reduce waste and utilise resources efficiently.

Approximately one-third of food produced for human consumption is lost or wasted globally, reflecting similar patterns across various countries. Polymeric materials in food packaging protect food but are primarily non-biodegradable, posing environmental risks. Therefore, there is an urgent need for biodegradable polymeric materials that are safe, cost-effective, and easily disposable to address this ecological threat in food packaging [48].

The EU’s 2020 Green Deal focuses on reducing waste exports and establishing regulations for biodegradable and bio-based plastics. This aims to improve local waste management, advance recycling, and decrease reliance on biodegradable plastics. The broader objective is to promote circular and bioeconomies, with plans to revitalise rural areas through a new financial strategy. This comprehensive approach targets improved waste management, sustainable material practices, and economic development in rural regions through strategic financial planning.

According to the European Regulation 1935/2004 [49], adequate packaging must fulfil several crucial functions, especially regarding food products. These include physical factors, such as safeguarding food from harmful substances such as dirt, dust, oxygen, light, pathogenic microorganisms, and moisture. Appropriate packaging should be inert, cost-effective to produce, and easy to dispose of or reuse. This is important because of the growing issue of packaging waste. Additionally, approximately one-third of the food produced globally is lost or wasted, totalling around 1.3 billion tonnes each year, which comes at a cost of over $1 trillion [50]. Therefore, new forms of food packaging, active and intelligent systems, as well as biodegradable multifunctional packaging, may help to make food products more stable during storage.

Biopolymers have garnered significant attention due to their ability to offer desirable properties suitable for diverse packaging applications [51]. The global production of biopolymers is projected to grow substantially and this anticipated increase underscores the rising interest and investment in biopolymer-based materials as viable alternatives in various industries, particularly packaging [51].

There is significant promise in developing innovative materials sourced from underutilised food components, renewable sources, and repurposed agro-industrial and marine leftovers. Integrating these resources within a circular economy framework enhances the value of waste materials and offers a sustainable alternative to non-renewable sources. These materials are often biodegradable and potentially edible, sourced from underutilised foods, renewable resources, and the reclamation of agro-industrial and marine by-products, among other potential sources [52]. This approach fosters sustainability by utilising overlooked resources, reducing waste, and offering eco-friendly material alternatives.

4. Legal Aspects and Regulations

The European Bioplastics Organisation (EBO) defines ‘bioplastics’ as plastics derived from either a bio-based origin or possessing biodegradable properties. According to the 2014 Bio-Based Products Vocabulary, plastics made from plant-based materials, or biomass, are classified as bio-based plastics [53]. However, regarding edible packaging composed of edible ingredients, such as food additives, the regulations are the same as for food products.

Escalating concerns about environmental impacts have spurred various policy interventions and voluntary initiatives targeting the reduction or elimination of single-use plastics. Policies and regulations have been introduced, including bans on single-use plastics [54]. Voluntary collaborations and pacts, like the European Plastics Pact and commitments by entities such as the Ellen MacArthur Foundation, aim to foster a circular economy for plastics, specifically addressing challenges related to plastic food packaging. Additionally, the establishment of the United Nations’ 17 Sustainable Development Goals (SDGs) has encouraged companies to promote sustainable practices. These goals include renewable resource utilisation without harming human health, addressing climate change, and preserving life below water and on land. Extended Producer Responsibility (EPR) is a policy mechanism that requires producers to be legally and financially accountable for reducing the environmental impacts of their products throughout their lifecycle. EPR is crucial in addressing plastic pollution by encouraging producers to design more sustainable products, reducing waste generation, and promoting recycling and proper disposal practices. This approach effectively mitigates plastic products’ environmental, health, safety, and social impacts.

As defined by Commission Regulation (EC) No 450/2009 of 29 May 2009 on active and intelligent materials and articles intended to come into contact with food [55], active packaging goes beyond traditional functions to interact with products or their environment, enhancing quality, extending durability, or providing extra consumer benefits. It may contain various active substances like antibacterials or antioxidants. Intelligent packaging has sensors or indicators that monitor and control product or packaging conditions. It provides data on parameters like quality, temperature, or contamination and can react to changing conditions by alerting about temperature breaches or expiration dates. The increase in biodegradable packaging has led to regulatory attention, focusing on defining biodegradability and monitoring environmental claims.

5. Biopolymer-Based Edible Food Packaging

The production and disposal of packaging materials after use result in various emissions, including carbon monoxide, hydrochloric acid, chlorine, dioxins, amines, furans, nitrides, benzene, styrene, butadiene, and acetaldehyde. These emissions profoundly impact the environment and are dangerous to human health. This is one of the reasons why biodegradable packaging materials are increasingly replacing synthetic packaging materials [56]. Biodegradable materials are sourced from various origins, including plants, animals, and microorganisms. It is essential that these materials are produced economically and sustainably, and that they decompose rapidly after disposal, typically through natural chemical or biochemical processes [17]. Biodegradable packaging is designed to naturally break down under specific environmental conditions and within set timeframes. It is typically made from plant-based materials such as starch, cellulose, polylactic acid (PLA), or polyhydroxyalkanoate (PHA). Unlike traditional packaging, biodegradable options can decompose or be composted after use, significantly reducing their environmental impact [57].

Composting is a natural process of decomposition of organic materials in oxygen, creating compost rich in organic nutrients. It is essential that compostable packaging meets appropriate standards and certifications, such as EN 13432 [58] or ASTM D6400 [59], to ensure proper behaviour during composting. Compostable packaging that meets these standards can be safely composted in specially designed installations. It is worth noting that compostable packaging requires specific composting conditions, such as appropriate temperature, humidity and access to oxygen, to be fully biodegradable.

Research has identified various biological materials, including proteins, polysaccharides, and lipids, as suitable components for developing biodegradable packaging. To improve the functionality of these materials, they are often enhanced with bioactive ingredients such as antimicrobials, antioxidants, vitamins, and flavonoids [60]. These packaging materials fulfil two functions: delivering bioactive compounds such as antimicrobials and antioxidants to enhance food products’ nutritional value while also extending their shelf life [61].

5.1. Polysaccharides

Starch and its derivatives, such as amylose starch and hydroxypropylated high amylose starch, have been recognised as viable alternatives to petroleum-based plastics. However, they face challenges like poor moisture resistance and mechanical fragility [62]. Improving the effectiveness of starch-based biodegradable packaging can be achieved by incorporating bioactive compounds. Various in vitro studies have shown that combining starch with bioactive materials, such as plant-based extracts, can impart bioactivity to starch films [63,64].

Chitin, a natural biopolymer, is widely found in the exoskeletons of crustaceans, fungal cell walls with similar biological compounds. Structurally akin to cellulose, chitin features an acetamide group, replacing the hydroxyl group on each monomer [65]. Both chitosan and chitin represent biodegradable polymers renowned for their exceptional film-forming capability and antimicrobial activity without the need for the introduction of additives [66]. In a study by Pavinatto et al. [67], applying chitosan coatings on strawberries exhibited a germicidal effect against bacteria and fungi. The authors observed that the coatings did not alter the visual appearance, aroma, texture and flavour of the strawberries, thus guaranteeing a good acceptance of the coated fruit.

Cellulose and its derivatives, such as carboxymethyl cellulose (CMC), hydroxypropyl cellulose (HPC), and bacterial cellulose (BC), have excellent film-forming properties They result in the creation of biodegradable, non-toxic, and transparent films [68,69].

Pectin, composed of poly-α-(1–4)-D-galacturonic acid chains with varying methyl esterification, is recognised for its biocompatibility, biodegradability, and gel-forming ability [70,71]. However, pectin films face limitations in mechanical performance compared to other polymers. Pectin-based films are suitable for short-term fruit and vegetable preservation, particularly in applications requiring water dissolution, like sachets [5].

Gums, as naturally occurring polysaccharides, can absorb water and create a gel, making them a focus of extensive research. They offer several advantages, such as being safe, sustainable, and biodegradable, making them an excellent choice for developing edible packaging materials [72]. They have also shown potential in supporting blood pressure regulation, renal functions, and the treatment of skin lesions [73,74].

Alginate is a biodegradable, biocompatible, and safe polysaccharide derived from seaweed. It consists of linked α-D-mannuronate (M) and β-L-guluronate (G) monomers, and it is both water-soluble and indigestible [75]. Known for its exceptional gelling and film-forming properties, alginate reacts with polyvalent metal ions to create strong intermolecular associations between chains via carboxylate and hydroxyl functional groups, resulting in both strong and weak bonds [76]. Chen et al. [77] utilised thymol within sodium alginate-based biodegradable films and applied it to fresh-cut apples to extend their shelf life. This approach mirrors similar applications seen in other food products. For instance, composite coatings and films made from crosslinked alginates have been used in preservation on various foods such as mushrooms [78], peaches [79], and fresh-cut cantaloupes [80].

5.2. Proteins

Whey is an active milk protein frequently used in baby formulas and sports supplements. It is recognised for its outstanding film-forming properties. Films created from whey protein exhibit strong mechanical strength and effective gas barrier functions, especially in low relative humidity conditions. However, research by Calva-Estrada et al. [81] indicates that this strength decreases as relative humidity increases.

Casein, which is a major component of milk protein, has remarkable film-forming abilities, resulting in flexible and transparent films [82]. However, casein films without additives tend to shrink during the drying process, thus becoming brittle. To avoid such a phenomenon, edible plasticisers, such as glycerol, are used to improve film elasticity by lowering their glass transition temperature [83]. Research by Picchio et al. [84] (2018) emphasises proteins as promising materials for developing edible packaging films whose properties can be improved by functional compounds. Tannic acid, a low-cost plant-derived phenolic compound, was shown to be an effective crosslinking agent for casein protein. The resulting films exhibit improved physicochemical properties and can be used in food packaging applications.

Zein, a prolamin protein found in corn, is a promising material for commercial edible packaging. This substance, insoluble and thermoplastic in nature, exhibits exceptional film-forming properties, as highlighted in studies by Zhu et al. [85] for zein/corn fibre gum complexes (2019), and Zhang et al. [75] for zein/chitosan formulations. Zhang et al. [86] found that mushrooms packaged in a blend film of zein and chitosan, with a mixing ratio of 1:1, showed the lowest rates of weight loss, respiration, and relative leakage. Additionally, these mushrooms had reduced levels of polyphenol oxidase and peroxidase activity, while exhibiting the highest whiteness index compared to other samples.

Gelatin is a denatured protein derived from the partial thermal hydrolysis of collagen, recognised for its outstanding gelling properties. It is commonly used in the manufacture of packaging materials and edible coatings [87]. They observed that freeze-dried bars coated with pork gelatin-based coatings at concentrations of 8%, 10%, and 12% have the potential to be used in the food industry as products with enhanced durability and resistance to external factors such as moisture and contamination. The composition of the coatings, along with the coating method, significantly affects the physical properties of the freeze-dried vegetable bars. This was confirmed by comparing gelatin-based coatings with self-standing films made from vegetable broth and gelatin. The application of edible films does not affect the internal structure of dried material. The barrier created by the coating forms a “pocket” that remains loosely attached to the surface of the bar. Additionally, edible films that incorporate vegetable broth demonstrate greater elasticity compared to those made entirely from gelatin. Therefore, the versatility of gelatin extends to various applications, including food, pharmaceuticals, and nutraceuticals, as highlighted in Łupina et al. [88]. Gelatin is also an excellent stabiliser for creating film-forming solutions, making it valuable in the production of various types of films. The incorporation of nanocomposites into gelatin-based films shows significant promise, especially in biomedical applications, as mentioned by Shankar et al. [89].

Soy proteins, including isolates (90% protein) and concentrates (70% protein), are by-products of the oil industry and represent an affordable and biodegradable material suitable for creating edible films and coatings, as noted by Tian et al. [79]. Despite being cost-effective and biodegradable, soy protein films have limitations. Their mechanical and barrier effectiveness are generally inferior to synthetic films. Additionally, their hydrophilic nature and sensitivity to environmental conditions contribute to these drawbacks [90,91].

5.3. Lipids

Lipids are known for their excellent barrier properties and have historically been used in fruit coatings, particularly paraffin and waxes for citrus fruits. However, their weak mechanical strength (no capacity for self-standing property) and lack of transparency have prompted their effective use in developing composite edible films, as noted in research by Thakur et al. [92]. Various strategies for improvement have been used to utilise the advantages of lipids in edible packaging formulations. These strategies include employing them as a combination of hydrophobic and hydrophilic layers or creating emulsified films and coatings.

Waxes, composed of long carbon chains, can be natural or synthetic, sourced from various compounds like carboxylic acids, esters, hydrocarbons, alcohols, and sterols. Research by Goslinska and Heinrich [93] highlights this diversity. Incorporating waxes into composite films and coatings has proven beneficial and was deeply explained in the case of carnauba wax by Susmita Devi et al. [94]. It reduces weight loss in fruits and vegetables while improving the barrier properties and thermal stability of coatings and films. Studies by Formiga et al. [95], Galus et al. [96] and Oregel-Zamudio et al. [97] demonstrate these advantageous effects, indicating waxes’ potential for preserving and improving properties in food-related coatings and films.

5.4. Edible Films and Coatings from Food Waste

To create sustainable food packaging, the use of food waste, such as processing leftovers, has become a key strategy. Food waste, which is rich in polysaccharides, proteins, and essential bioactive components such as carotenoids and antioxidants, is increasingly being used in the development of biodegradable packaging. Studies, such as those by Kurek et al. [98], have shown the effectiveness of waste sources like banana peels, apple peels, pomegranate peels, citrus peels, and others in producing composite biodegradable packaging. This trend involves investigating various waste materials, including restaurant waste, agricultural residues, and post-harvest food waste, for potential uses in future food packaging [99]. These materials represent a beneficial resource for developing eco-friendly packaging solutions while also contributing to waste reduction efforts [100].

6. Preparation Methods for Biopolymer-Based Packaging

Films, in the context of food packaging, are created as individual layers through a process involving casting and drying (Figure 3). These films are developed and shaped into suitable forms and self-standing structures for practical applications. The casting method, outlined by Tavassoli-Kafrani et al. [76] for independent forms and edible coatings, ensures the preservation and safeguarding of food items during storage or transportation. Xu et al. [101] discussed the importance of data-driven materials discovery in developing novel functional coatings. They emphasised that this approach can effectively identify and optimise the properties of bio-based materials for specific applications. In contrast to traditional trial-and-error methods, which can be time-consuming and yield unsatisfactory results, the data-driven interdisciplinary methodology offers a more efficient way to create coatings. This can result in products with enhanced durability, improved performance, and even the ability for in situ self-adaptation across various applications.

Nanotechnology has enabled the development of innovative nanoscale edible coatings, which are approximately 5 nm thick. These coatings can be used for packaging a variety of food items, including meats, cheese, fruits, vegetables, confectionery, baked goods, and fast food products. The nanoscale coatings provide benefits by serving as a barrier to moisture and regulating gas exchange. Moreover, they serve as a vehicle for delivering colours, flavours, antioxidants, enzymes, and anti-browning agents, thereby potentially extending the shelf life of manufactured foods [102].

Encapsulation technologies are mainly used to protect flavours and aromas in packaged foods while allowing for controlled release. Hydrophilic materials, such as biopolymers (polysaccharides or proteins), are used to encapsulate hydrophobic agents, whereas hydrophobic polymers are employed to encapsulate hydrophilic compounds. Encapsulated substances are classified based on their size into macro, micro, and nano capsules [103]. Nanoencapsulation, a technology involving capsules with nanometre-sized dimensions, plays a crucial role in providing functionalities within products, such as the controlled release of active ingredients. This technology has proven be beneficial in protecting various compounds such as vitamins, antioxidants, antimicrobial or antifungal compounds, proteins, probiotics, lipids, or carbohydrates. This technology has been instrumental in creating functional foods followed by enhanced stability and functionality [104]. In the food industry, nanoemulsions find widespread application, especially in packaging, for delivering active agents to solid foods, encapsulated essential oils, and nanoemulsified edible materials [102].

7. Fast-Dissolving Edible Pouches for Food Applications

Fast-dissolving edible films offer great potential, particularly in portioned dry foods and premeasured ingredient packets. Some examples of these edible pouches from our previous research are presented in Figure 4. Those structures enhance convenience in consumer goods and food production by enabling precise measurements without the need for scoops or skilled labour. Additionally, these films seal pouches tightly, extending food shelf life by controlling mass transfer. It is essential to achieve both rapid dissolution and protective functions for their effective integration into various food packaging applications [27].

The edible film should be thin, available in various sizes and shapes, unobstructed, have excellent mucoadhesion, should undergo fast disintegration without water, and have a rapid release [105]. Convenient dosing, no water needed, no risk of choking, taste masking, enhanced stability, improved patient compliance, more flexible, easily handled storage and transportation; because the medicine enters the systemic circulation immediately, it has the quickest beginning of therapeutic activity [106]. It provides ease of administration for paediatric and geriatric patients who face the problem of dysphasia; with a diminished hepatic first-pass impact, the medication penetrates the systemic circulation [107]. High doses cannot be included in the oral strip due to technical challenges related to dose uniformity. Additionally, medications that irritate the oral mucosa or are unstable at mucosal pH cannot be administered this way. Oral strips are sensitive and must be kept dry, requiring specific packaging to protect them from moisture.

The three types of fast-dissolving technology are as follows: lyophilised systems, compressed tablet-based systems, and oral thin films [108]. Oral films are thin, flat films that are placed in the mouth. Dissolvable oral thin films (OTFs), also known as oral strips (OS), originated from the confectionery and oral care industries as breath strips. Over the years, they have evolved into a unique and highly recognised method for delivering vitamins and personal care products to consumers. To create a 50–200 mm film, these methods utilise a range of hydrophilic polymers [109].

The methods for preparing orally fast-dissolving films include the solvent casting method, the semisolid casting method, the hot melt extrusion method, the solid dispersion extrusion method, and the rolling method [107]. Packing considerations are essential for ensuring the storage, protection, and stability of the dosage form.

Edible pouches have wide-ranging applications across industries. They are used to package food items like snacks, condiments, beverages, and dry ingredients, preserving freshness and reducing waste. Additionally, they serve as single-use items for condiments, sugar or creamer packets, and even edible straws. In pharmaceuticals, they hold promise for individual dose packaging and oral medication delivery. Their sustainability reduces plastic waste, making them an eco-friendly alternative. These pouches can also be customised for personalised nutrient blends or dietary supplements, ideal for convenient consumption. In event catering, they reduce disposable packaging needs for individually wrapped or portioned foods. Their portability suits active lifestyles, providing easily consumable options. Finally, chefs experiment with edible packaging as creative elements in dishes, using it as containers or garnishes.

One of the most anticipated uses of edible films that dissolve quickly upon contact with water is for individually portioned dry food products, such as those that extend the shelf life of incompatible ingredients in recipes. Such applications can increase functionality, such as convenience, not only for consumer packaged goods but also for food services and industrial-scale food production [27]. Using precisely measured ingredients can streamline delivery, allowing for easy scooping and measuring without the need for tools. This results in accurate ingredient quantities that are dust-free, requiring less clean-up and less dependence on skilled cooks or workers. However, for this application, simply having edible films or coatings is not sufficient. Edible packaging must dissolve completely and instantly in a way that aligns with consumer expectations [17].

Current research has significantly emphasised employing edible pouches with high oxygen-barrier and antioxidative efficiency. This attention stems from the recognition that oxidation is a critical detrimental factor responsible for diminishing the shelf life of food products containing lipids [35]. The development of rancidity in edible oil or oil-rich products can result in an unpleasant taste in food, leading to reduced sensory appeal, compromised nutritional value, and a shortened duration of freshness. As oxidation progresses, it generates various by-products that can potentially be harmful or toxic [110]. Adding antioxidants into packaging materials allows them to migrate from the material to the food, where they can promptly neutralise free radicals formed during lipid oxidation. This process effectively hinders the spread of oxidation reactions on the surface of food products [111]. Yet, there is a rising consumer demand for food products devoid of synthetic antioxidants, as natural antioxidants are perceived as healthier. Interestingly, biodegradable films derived from proteins inherently possess some antioxidant properties themselves [112]. Simultaneously, these biodegradable films also demonstrate low oxygen permeability, specifically under conditions of low relative humidity.

In a study conducted by Hromiš et al. [31], multicomponent films were developed using pumpkin oil cake (PuOC) and a combination of pumpkin oil cake and maize zein. The findings revealed that films based on PuOC demonstrated effective oxidative stability, indicating their potential as protective pouches for fatty food items. However, while these films maintained the oil’s composition without significant changes, the sensory quality of the oil was observed to be somewhat less satisfactory. In the study conducted by Tagrida et al. [23], gelatin/chitosan blend films were investigated, incorporating various plasticisers and liposomes loaded with betel leaf ethanolic extract at concentrations of 2% or an equivalent amount of extract. The research focused on shrimp oil stored in pouches made from gelatin/chitosan blend films, plasticised with glycerol, and integrated with betel leaf ethanolic extract. During storage at room temperature, the shrimp oil packaged in novel pouches exhibited reduced oxidation compared to shrimp oil stored in lower-density polyethylene pouches.

In the study of Cho et al. [30], a novel film pouch was created by combining corn zein with soy protein isolate to package olive oil condiments for instant noodles. Adding the corn zein film layer improved tensile strength and water barrier properties, but at the expense of reduced elongation at break and oxygen barrier capabilities compared to the soyfilm. Despite some drawbacks, this novel bilayer film demonstrates the potential for packaging applications, highlighting a trade-off between different mechanical and barrier properties.

Milk and dairy products are essential sources of nutrients, crucial for children’s growth and for maintaining adult health. Although cheese is one of the most varied dairy products, its shelf life is limited by microbial activity. Ryu et al. [29] aimed to assess the best packaging method for individual cheese slices. Among the four types of edible pouches tested, the pouch containing zein and oleic acid proved most effective, maintaining superior cheese quality in terms of physical and microbiological aspects during a 4-week storage at 5 °C. Interestingly, cheese packed in the inner edible pouch and then re-packed in conventional plastic outer pouches showed comparable quality to cheese packed individually in plastic pouches, suggesting the potential for combining these materials to maintain cheese quality effectively.

Meat, characterised by its tissue composition, undergoes various treatments that can promote microbial growth. In recent times, antimicrobial and intelligent packaging have emerged as crucial technologies to ensure food safety. Given the extensive range of meat products available, there is a necessity for diverse approaches to control food-borne pathogens and extend the shelf life of these products [113].

Edible films and coatings play a crucial role in improving the mechanical properties, as well as the gas and moisture barriers, of meat products. Various techniques such as dipping, spraying, casting, brushing, individual wrapping, or rolling are used to apply these edible films. Mathew et al. [114] introduced biodegradable films crafted from a mix of PVA-montmorillonite K10 clay nanocomposites infused with silver nanoparticles derived from ginger extract. These films displayed exceptional antimicrobial abilities against common foodborne pathogens like S. Typhimurium and S. aureus. Moreover, these advanced films exhibited improved mechanical strength, water resistance, and light-blocking features compared to standard films. Employed in packaging pouches, they effectively reduced microbial contamination in chicken sausage samples. Díaz et al. [115] compared two packaging methods for a refrigerated pork-based dish. One method involved sous vide (SV) vacuum sealing, while the other used a modified atmosphere in polypropylene trays (PT) sealed with a top film. Both methods underwent cooking at 70 °C for 7 h, followed by chilling at 3 °C and storage at 2 °C for up to 90 days. Although the SV method showed faster heat penetration during cooking (2 °C/min vs. PT’s 1 °C/min), both methods equally prevented microbial spoilage throughout the 90-day storage at 2 °C. This suggests that both techniques are effective in ensuring food safety and preservation for extended refrigerated storage.

8. New Types of Food Packaging Systems

Modern food packaging techniques are valuable for food applications. Smart packaging, which includes active and intelligent systems, offers more precise information regarding the conditions of food products. They can also provide a protective effect when functional compounds are used, such as antioxidant or antimicrobial agents [116]. Figure 5 shows the divisions and examples of smart packaging, which can be in the form of pouches based on bio-based materials.

Active packaging refers to integrating specific additives into polymer materials, packaging films, or containers to actively sustain and extend the shelf life of products. This approach incorporates various additives aimed at scavenging oxygen, absorbing carbon dioxide, moisture, ethylene, undesirable flavours or odours, as well as releasing antioxidants, preservatives, ethanol, sorbates, or regulating the temperature within the packaging [117,118]. Active packaging is developed to interact with the surrounding environment of the food, inside of the packaging or around the product without packaging, to maintain its quality and extend its shelf life. It involves adding specific substances to packaging materials to create a controlled atmosphere around the food without directly introducing these components into the food itself. Some key functionalities of active packaging include absorption (oxygen, ethylene, moisture, or unwanted odours) and emission (carbon dioxide, antimicrobial agents, antioxidants, or specific aromas) [119]. Antimicrobial agents, both natural (i.e., plant extracts and essential oils, bacteriocins, enzymes) and synthetic (i.e., organic acids, potassium sorbate), incorporated into the packaging can inhibit the amount and the growth of bacteria or fungi, enhancing food safety. Antioxidants are able to prolong the shelf life of food by preventing or slowing oxidation reactions that cause food deterioration. Aromas might be released to enhance the sensory experience of the food [120]. Bioactive packaging represents an innovative technology that directly influences consumer health by promoting the creation of healthier packaged foods. This approach utilises biopolymers capable of retaining specific beneficial bioactive compounds under optimal conditions until their controlled release into the food product [121]. Techniques such as enzyme encapsulation, enzyme immobilisation, microencapsulation, and nanoencapsulation are employed to achieve this controlled release, ensuring the preservation of these bioactive principles until they positively impact the food product [10]. Smart or intelligent packaging represents an innovative and interdisciplinary technology that combines knowledge from various fields, such as physics, chemistry, biochemistry, electronics, and food science and technology. This specialised packaging method includes various chemical sensors and biosensors to monitor the quality and safety of food products. These sensors are adept at assessing factors like food freshness, pH levels, oxygen and carbon dioxide levels, presence of pathogens, gas leakage, ripeness indicators, bioprobes, radio frequency signals, toxin levels, and the time-temperature history of the product [119]. Essential oils have become crucial components in creating active packaging edible films. These oils, sourced from various origins like marigold flower, oregano, grape seed, clove, and thyme, have been combined with diverse polymers, resulting in improved functional properties of biodegradable films. Research conducted by Salama et al. [122] and Heydari-Majd et al. [123] highlights these advancements, particularly in enhancing preservation methods for fruits and vegetables. Essential oils included to biodegradable films contribute antioxidants and antibacterial properties, as evidenced by studies from Moghimi et al. [124] and Hashemi et al. [125].

9. Future Trends and Perspectives

Edible pouches offer a promising solution for reducing plastic waste, but they face several limitations that hinder widespread adoption. These include challenges with mechanical strength, barrier properties—particularly against moisture, light, and oxygen—and achieving regulatory approval. Additionally, consumer perception and the potential for flavour contamination can be barriers. Future studies should focus on optimising the relationship between the film’s formulation and composition, specifically regarding the amounts of biopolymers and functional materials. The technique used for preparing edible pouches should also be similar to those used in the packaging industry to reduce production costs.

10. Conclusions

Packaging is essential for protecting food products, maintaining their freshness, and preserving quality from production to consumption. In the food processing industry, biopolymeric films are becoming increasingly popular as a solution to the disposal problems associated with traditional polymer packaging. Biopolymers are considered sustainable alternatives to synthetic polymers, representing a new generation of food packaging materials. Fast-dissolving packaging, such as edible pouches, minimises environmental impact by rapidly breaking down under specific conditions, like water or heat, reducing waste. Moreover, pouches can be enhanced by functional compounds, such as antimicrobials or antioxidants, and play a role as active or/and intelligent food packaging. They can be applied to dry food such as powders, coffee or tea and to oils or other food products, mostly with low moisture content due to the usually hydrophilic character of biopolymer-based packaging films. Edible pouches offer diverse applications across various industries, promising innovative solutions in food packaging, consumption, and sustainability in areas such as food packaging, pharmaceuticals, environmental solutions, personalised nutrition, event catering, convenience, and culinary uses.