Valorization of Fruit and Nut Agricultural Residues for Sustainable Biomaterials and Biotextiles: A Qualitative Review with Strategic Insights for Greece

Abstract

The growing environmental impacts associated with conventional plastics and textiles have intensified interest in bio-based and circular material alternatives. This study presents a qualitative and structured literature review of the valorization of fruit and nut agricultural residues as sustainable feedstocks for biomaterials and biotextiles, with a strategic focus on Greece. Drawing on international literature, regional agricultural production data, and validated processing technologies, the review synthesizes existing evidence on residue availability, conversion routes, environmental performance, and market trends. The reviewed literature indicates that residues such as grape pomace, olive by-products, citrus peels, and nut shells have been widely reported as suitable sources of cellulose, lignin, and pectin for the development of fibers, films, and composite materials. Findings from published life cycle assessment (LCA) studies suggest potential reductions in water use, greenhouse gas emissions, and land-use intensity compared with conventional cotton and synthetic textiles, although results vary depending on system boundaries and processing conditions. The review further highlights enabling factors, technical limitations, and policy considerations relevant to the Greek context. This study provides a qualitative integrative perspective on the opportunities and constraints associated with agricultural residue valorization, identifying key research gaps and strategic directions for future development within Greece and similar Mediterranean regions.

1. Introduction

The global textile and materials industries are increasingly identified as major contributors to environmental degradation due to their heavy reliance on petroleum-based polymers and resource-intensive natural fibers such as conventional cotton [1]. These production systems are associated with high greenhouse gas emissions, excessive water and energy consumption, extensive land use, and the generation of persistent waste streams, including microplastics and chemically complex effluents [2]. The rapid expansion of fast-fashion business models has further intensified these impacts by accelerating production cycles and shortening product lifetimes, thereby increasing material throughput and post-consumer textile waste [3].

In response to these challenges, bio-based materials have emerged as promising alternatives to fossil-dependent production systems, particularly when integrated within circular economy strategies [4]. Among available bio-based feedstocks, agricultural residues have attracted increasing attention due to their availability as unavoidable by-products of food production and agro-industrial processing [5]. Fruit and nut residues, including peels, pomace, shells, pruning waste, and stalks, are rich in lignocellulosic polymers such as cellulose, hemicellulose, lignin, and pectin, which can be converted into fibers, films, coatings, and composite materials suitable for textile and technical applications [6]. Their utilization avoids competition with food systems and does not require additional agricultural land, supporting more efficient resource use and waste minimization [7].

At the global level, the valorization of agro-industrial waste into biomaterials and biotextiles has progressed substantially over the past decade [8]. Numerous experimental and pre-commercial studies demonstrate that residues from fruit and nut production can be transformed into regenerated cellulose fibers, bio-based leather alternatives, functional textile finishes, and biodegradable composites with mechanical and aesthetic properties comparable to conventional materials [9]. LCA studies consistently report significant reductions in water use, cumulative energy demand, and greenhouse gas emissions when agricultural residues are used as feedstock instead of virgin polymers or dedicated fiber crops [10]. These environmental benefits are particularly pronounced when regional sourcing and decentralized processing models are employed [11].

Several pioneering industrial initiatives and research-driven demonstrations further illustrate the technical feasibility and growing market relevance of agricultural residue valorization in the textile sector [7,8]. Citrus peels have been successfully converted into regenerated cellulose fibers suitable for apparel applications, while grape pomace has enabled the development of bio-based leather-like materials for fashion and interior uses [12,13]. Similarly, pineapple leaves, banana pseudostems, nut residues, and stone fruit processing wastes have been explored as alternative lignocellulosic feedstocks for the production of fibers, bioplastics, and composite materials targeting textiles, footwear, and automotive interiors [9,14,15,16,17]. In this context, recent studies have demonstrated the upcycling of industrial fruit-processing residues, such as peach waste, into high-purity dissolving-grade cellulose pulp exhibiting physicochemical and morphological properties comparable to commercial textile pulps, thereby confirming the suitability of fruit waste streams for regenerated cellulosic fiber production [18].

In parallel, advances in green chemistry, enzymatic and biological processing, ultrasonic-assisted treatments, and low-impact finishing technologies have expanded the functional scope of biotextiles [19,20]. These approaches enable the incorporation of antimicrobial, UV-protective, antioxidant, and other multifunctional properties while reducing reliance on toxic synthetic additives, heavy-metal mordants, and resource-intensive wet-processing routes [21]. Such developments are particularly relevant for improving the environmental performance and market acceptance of bio-based textiles in high-value applications.

Despite substantial technological progress, regional disparities persist in the adoption and industrial scaling of agro-residue-based biomaterials, particularly across Southern Europe [22]. Greece has not yet fully exploited its extensive agricultural residue streams beyond low-value applications such as energy recovery, animal feed, or disposal, despite being a major producer of olives, grapes, citrus fruits, figs, almonds, and other crops [23,24]. These activities generate large volumes of lignocellulosic residues with significant potential for conversion into value-added biomaterials and biotextiles, representing an opportunity to reduce waste management pressures while supporting rural economic development and regional industrial diversification.

Within this context, fruit and nut agricultural residues can be reframed from waste streams into strategic resources for sustainable material production. This study aims to provide a structured and critical review of existing literature on residue availability, processing technologies, environmental evidence, and market developments within the broader European bioeconomy transition, with a focus on Greece. The work synthesizes current knowledge to identify opportunities, constraints, and research gaps relevant to residue-to-biomaterial value chain development. Despite the growing body of literature on agro-industrial residue valorization, existing reviews predominantly focus on material science aspects, laboratory-scale extraction techniques, or global technological trends without adequately integrating regional biomass availability, techno-economic considerations, environmental evidence, including findings from LCA studies, and policy context. Furthermore, few studies systematically position Southern European countries within the broader EU bioeconomy transition to assess scale-up potential and structural constraints. This study addresses this gap by providing a qualitative and integrative synthesis of the available evidence, combining insights on residue availability, processing pathways, reported environmental performance, market dynamics, and policy frameworks, using Greece as a case study while deriving insights applicable to other Mediterranean agro-industrial regions.

2. Literature Review Methodology

This study adopts a qualitative structured literature review methodology, combining systematic literature retrieval with interpretative synthesis of published data. The objective is not to perform independent quantitative assessments, but to critically analyze and integrate existing evidence on agricultural residue valorization pathways, environmental performance, and market developments relevant to biomaterials and biotextiles, with a strategic focus on Greece.

2.1. Literature Search Strategy

Scientific literature was retrieved from Scopus, Web of Science, and ScienceDirect databases. Other sources included official publications from the European Commission, FAO, UNIDO, and national agricultural statistics. The search covered the period 2010–2025.

Boolean search strings: Scopus (TITLE-ABS-KEY) (“agricultural residues” OR “agro-waste” OR “fruit waste” OR “nut shells” OR “grape pomace” OR “citrus peels”) AND (“biomaterials” OR “biotextiles” OR “bio-based fibers” OR “cellulose fibers” OR “biocomposites”) AND (“life cycle assessment” OR “LCA” OR “environmental impact” OR “sustainability”) AND (PUBYEAR > 2009 AND PUBYEAR < 2026).

Equivalent keyword structures were applied to Web of Science (Topic search) and ScienceDirect (Title-Abstract-Keywords). Particular emphasis was placed on incorporating peer-reviewed publications from 2023–2025 to capture recent advances in lignocellulosic fractionation, regenerated cellulose fiber production, and circular textile LCA modeling.

2.2. Screening and Selection Procedure

After duplicate removal, 312 sources were identified. Title and abstract screening reduced this to 168 records. Following full-text evaluation, 103 sources were retained:

• Peer-reviewed journal papers: 80;
• Books/edited volumes: 6;
• Policy & standards (EU, ISO, FAO, EEA, EC, etc.): 14;
• Industry/market/NGO/reports (Statista, Fortune Business Insights, Vogue Business): 3.

Inclusion criteria required:

• Relevance to agricultural residue valorization;
• Documented material or processing pathways;
• Environmental, technical, or economic assessment.

Included studies were qualitatively assessed for methodological robustness, including transparency of system boundaries in LCA studies, clarity of functional units, reporting of impact categories, and technical reproducibility of processing routes. Studies lacking defined system boundaries or impact quantification were treated as contextual references rather than primary analytical inputs. Market data derived from sources such as Statista and industry reports were used for contextual purposes only. Where applicable, these data were cross-referenced with original datasets or institutional reports, and their limitations in terms of transparency, methodology, and reproducibility were considered in the qualitative interpretation.

2.3. Data Sources

Table 1. Data categories and corresponding sources used for the assessment of agricultural residue valorization pathways and related market, environmental, and policy dimensions.

Data Category	Source Type
Agricultural production volumes	FAOSTAT, national statistics
Residue characteristics & composition	Peer-reviewed literature
Biomaterial processing routes	Peer-reviewed scientific literature
Environmental performance (LCA)	Published LCA research
Market forecasts	Statista, Fortune Business Insights
Policy framework	EU Circular Economy Action Plan, CBE JU

shows the main data categories used in this study and their corresponding sources. Specifically, agricultural production volumes were obtained from FAOSTAT and national statistics, residue characteristics and composition from peer-reviewed literature, biomaterial processing routes from scientific studies, environmental performance data from published LCA research, market forecasts from Statista and Fortune Business Insights, and policy information from the EU Circular Economy Action Plan and CBE JU documents.

2.4. Mapping and Visualization Methods

Figure 1 and Figure 2 (maps) were produced using the MapChart platform [25], which distributes maps under the Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license. Base maps were modified by the authors of this work to include regional color coding, residue categories, labels, and legends. All cartographic adaptations constitute derivative works compliant with the license. Figure 3 visually presents the structural elements based on established circular bioeconomy and cascading biomass utilization frameworks (inputs → extraction → processing → biomaterials → market use → end-of-life → nutrient return) [4,7,22].

2.5. Conceptual Structure of the Review

The study is organized around key thematic dimensions:

• Material science perspective: extraction and processing routes for cellulose, lignin, pectin, and polyphenols.
• Environmental sustainability synthesis: comparative LCA evidence.
• Economic and market evaluation: bio-based material market growth and IoT-enabled value chains.
• Regional biomass mapping: distribution of Greek agricultural residues.
• Circular bioeconomy systems approach: cascading biomass utilization and end-of-life pathways.

3. Global and Greek Context of Fruit and Nut Agricultural Residues

Agricultural and agro-industrial activities generate substantial quantities of residual biomass worldwide, much of which remains underutilized or is directed toward low-value applications such as composting, energy recovery, or disposal [5,8,26]. Fruit and nut processing in particular produces residues including peels, pomace, stones, shells, and fibrous pulp that are rich in lignocellulosic polymers and bioactive compounds, making them attractive feedstocks for biomaterials and biotextiles [6,9]. In recent years, increasing attention has been directed toward valorizing these streams as part of circular bioeconomy strategies that aim to close material loops and reduce environmental burdens associated with conventional material production [4,27].

At the global level, several regions have demonstrated early adoption of agricultural residue valorization pathways for textile and material applications. Representative examples of biotextile and biomaterial innovations derived from fruit and nut residues are illustrated in Figure 1, highlighting initiatives across Europe, Asia, and North America. These include the conversion of citrus-processing waste into regenerated cellulose fibers, the utilization of grape pomace for bio-based leather-like materials, and the exploitation of pineapple leaves, banana pseudostems, and other fruit residues for fiber, composite, and bioplastic production [8,9,12,13,14,15]. For example, in Italy, citrus-processing waste has been successfully converted at commercial scale into regenerated cellulose-based textiles, transforming a by-product of the juice industry into a value-added resource. Similarly, in Spain, sustainable materials derived from grape skins have been developed and commercialized, leveraging the abundant residues from the wine industry. In addition, an innovative leather-alternative material produced from pineapple leaves, typically discarded after fruit harvesting, has been developed through collaboration between the UK and the Philippines, demonstrating the potential of cross-continental partnerships in advancing agricultural residue valorization. Collectively, these cases demonstrate that agricultural residues can be transformed into commercially relevant materials when supported by appropriate processing technologies, market demand, and enabling policy frameworks.

Southern Europe occupies a particularly strategic position within this global landscape due to its high intensity of fruit and nut production and processing activities [11,22]. However, despite favorable climatic conditions and strong agricultural output, the region has not yet fully translated its residue availability into high-value biomaterial production at scale. Greece represents a characteristic case, combining substantial agricultural residue generation with limited industrial valorization beyond traditional uses [23,28]. This gap highlights both a challenge and an opportunity for the development of localized residue-to-biomaterial value chains.

In Greece, fruit and nut cultivation is geographically distributed across several regions, each characterized by distinct crop profiles and residue streams.

Table 2. Residue Generation from Greek Fruit and Nut Crops (2023) [5,24].

Crop	Region	Production (tons)	Residues (tons)
Olives	Crete	1,100,000	250,000
Grapes	Peloponnese	720,000	180,000
Citrus	Peloponnese	420,000	130,000
Almonds	Thessaly	85,000	25,000
Figs	Evia, Crete	70,000	20,000
Chestnuts	Northern Greece	30,000	8000
Total (Greece)		2,425,000	613,000

summarizes estimated production volumes and corresponding residue generation for major Greek fruit and nut crops in 2023, including grapes, olives, citrus fruits, figs, almonds, and chestnuts. Annually, Greece produces over 1 million tons of olives, alongside substantial outputs of grapes, citrus fruits, and nuts. These crops collectively generate hundreds of thousands of tons of lignocellulosic residues annually, providing a stable and renewable feedstock base for biomaterial and biotextile production. Importantly, these residues are largely produced as a consequence of food processing activities, ensuring their availability without additional land or resource inputs [5,24]. Globally, fruit and nut production exceeds approximately 1 billion tons annually [24], indicating that Greece represents a modest but regionally significant share of Mediterranean agricultural residue generation, particularly for olives and grapes.

The spatial distribution of residue streams highlights the potential for regionally adapted valorization strategies. Key agricultural regions such as the Peloponnese, Crete, and Thessaly contribute significant volumes of citrus, grape, olive, and nut residues, supporting the development of decentralized processing models aligned with local biomass availability (Figure 2).

Taken together, the global examples highlighted in Figure 1 and the national residue mapping presented in Table 2 and Figure 2 indicate that Greece possesses both the resource base and regional structure necessary to support agricultural residue valorization into biomaterials and biotextiles. The challenge lies in translating this potential into coordinated industrial activity through appropriate technological choices, supply chain organization, and policy support. The following sections therefore examine the protocols, technologies, and processing routes that enable the conversion of fruit and nut residues into high-value biomaterials and biotextiles.

4. Protocols, Techniques, and Technologies for Biomaterial and Biotextile Creation

The transformation of fruit and nut agricultural residues into high-value biomaterials and biotextiles involves a series of interconnected protocols, techniques, and technologies designed to extract, isolate, and convert lignocellulosic components into functional material forms. These processes aim to maximize resource efficiency, ensure consistent material quality, and minimize environmental impacts associated with conventional textile production routes [6,15,27,28]. A systematic understanding of these methodologies is therefore essential for supporting industrial scalability and sustainable implementation.

4.1. Raw Material Preprocessing

Before the extraction of valuable compounds, agricultural residues must undergo preprocessing steps that prepare the biomass for efficient fractionation and conversion [6,15,29]. These treatments are critical for reducing heterogeneity, increasing surface area, and improving the accessibility of target polymers [10,26,29]. Agricultural residues are primarily composed of lignocellulosic structures, including cellulose, hemicellulose, and lignin, arranged in complex matrices that require targeted preprocessing to enable efficient fractionation and material conversion [9,18]. The choice of preprocessing method depends on residue type, moisture content, and intended end use [5,6,19].

Mechanical separation involves physical size-reduction and fractionation techniques such as grinding, shredding, milling, and sieving [6,29]. These methods are commonly used to isolate fibrous fractions from pulp, stones, or seeds and to standardize feedstock characteristics [14,26,29]. For example, nut shells may be processed into powders or granules depending on their intended application as reinforcement fillers or fiber sources, while fruit peels are typically shredded to enhance subsequent chemical or biological treatments [6,14].

Chemical extraction employs acidic, alkaline, or solvent-based treatments to disrupt the lignocellulosic matrix and selectively solubilize biomass components [29,30]. Acid hydrolysis is frequently used to decompose hemicellulose into fermentable sugars, whereas alkaline treatments effectively remove lignin and increase cellulose accessibility [31]. Organic solvents may also be applied for the extraction of pectin, polyphenols, and waxes. Process parameters such as reagent concentration, temperature, and residence time are optimized to maximize yield while minimizing polymer degradation [29].

Biological methods rely on enzymatic or microbial activity to deconstruct complex plant cell walls [20]. Enzymatic hydrolysis using cellulases, hemicellulases, and pectinases enables selective polymer release under mild conditions, reducing energy input and chemical consumption [32]. Microbial treatments may further contribute to polymer modification or the production of bioactive co-products [33]. These approaches align strongly with green chemistry principles and are increasingly explored as sustainable alternatives to conventional chemical pretreatments [20,34].

In addition, the physicochemical variability of agricultural residues, including differences in lignin content, crystallinity index, moisture levels, and ash composition, plays a critical role in determining preprocessing efficiency and downstream material performance [6,29,31]. Such variability requires adaptive preprocessing strategies tailored to specific biomass types and seasonal conditions, as widely discussed in recent biomass valorization studies [15,18,33].

4.2. Fiber and Polymer Isolation

Following preprocessing, isolation of key polymers forms the basis of biomaterial and biotextile production [15,26,29]. Cellulose and lignin are the primary targets due to their abundance and favorable mechanical and functional properties [26].

Cellulose is the most abundant biopolymer in plant biomass and serves as the foundation for regenerated fibers and composite materials [35]. It consists of linear chains of β(1 → 4)-linked D-glucose units, forming highly ordered crystalline and amorphous regions that influence its mechanical strength, thermal stability, and processability [35]. Lignin, a complex aromatic polymer, contributes structural rigidity and is increasingly valorized as a bio-based additive or functional material component [28]. The lignocellulosic matrix, composed primarily of cellulose, hemicellulose, and lignin, forms a tightly bound composite structure in plant cell walls, requiring effective fractionation strategies for polymer isolation [29,31,35].

Separation techniques include traditional pulping methods (e.g., Kraft and sulfite processes) and more environmentally benign alternatives such as organosolv pulping [36]. These processes aim to selectively remove lignin and hemicellulose while preserving cellulose integrity [29,31,36]. The efficiency of these separation processes is governed by factors such as temperature, pH, solvent composition, and residence time, which directly influence polymer yield, purity, and structural integrity [26,29,36]. Chemical treatments, including alkaline or acid hydrolysis, are often combined with physical or enzymatic methods to further enhance fractionation efficiency and reduce degradation of target polymers [6,26,29]. Emerging approaches such as ionic liquid processing and deep eutectic solvents are also being explored to improve selectivity and reduce environmental impacts [10,36].

The effectiveness of polymer isolation is strongly influenced by the intrinsic recalcitrance of lignocellulosic biomass, arising from the complex cross-linked structure of cellulose, hemicellulose, and lignin [29,31,35]. Advanced fractionation strategies aim to selectively disrupt these interactions while preserving polymer functionality [26,36]. For instance, alkaline pretreatment enhances cellulose accessibility by removing lignin, whereas organosolv processes enable higher lignin purity suitable for material applications [29,31]. Emerging solvent systems, such as ionic liquids and deep eutectic solvents, have demonstrated improved selectivity and reduced environmental impact, although challenges related to cost, solvent recovery, and scalability remain under investigation in recent studies [10,36].

Isolated cellulose can be processed into viscose- or lyocell-type fibers, while lignin fractions can be utilized in advanced material formulations [31]. The properties of the resulting cellulose pulp, including degree of polymerization, crystallinity, and purity, are critical parameters influencing downstream fiber spinning performance and final material properties [26,35].

Beyond cellulose and lignin, pectin and polyphenols represent valuable co-products, particularly in fruit-derived residues [15]. Pectin extracted from citrus peels and apple pomace is widely used in food applications but also exhibits potential in biomedical materials, coatings, and films [37]. Polyphenols recovered from grape skins and pomace function as natural antioxidants, colorants, or functional additives, enhancing the performance and sustainability profile of biomaterials [38]. Co-extraction strategies increase overall resource efficiency and support zero-waste valorization models [39,40].

The scalability of these isolation processes further depends on factors such as feedstock variability, chemical consumption, energy requirements, and process integration, which are widely discussed in the literature as critical parameters influencing industrial feasibility [6,26,29,36].

4.3. Conversion to Biotextiles

Isolated polymers and fibers are subsequently converted into textile-compatible forms through diverse manufacturing pathways, depending on their physicochemical properties, intended applications, and processing requirements.

Fiber spinning transforms cellulose-based solutions or suspensions into continuous filaments suitable for weaving or knitting. Depending on polymer characteristics, wet spinning, dry spinning, or melt spinning techniques may be applied [41]. The selection of spinning method is influenced by solvent system, polymer molecular weight, and desired fiber properties [42]. For example, regenerated cellulose fibers produced via lyocell processes exhibit high tensile strength and uniform morphology due to controlled dissolution and extrusion conditions [42].

Natural fibers derived from agricultural residues, such as banana stems, coconut husks, and pineapple leaves, can be extracted through mechanical and chemical treatments including decortication, alkali treatment, and enzymatic processing [43]. These treatments remove non-cellulosic components such as lignin and hemicellulose, improving fiber-matrix adhesion and mechanical performance [29,31,43]. Fibers can then be blended with other natural or synthetic fibers to tailor mechanical strength, flexibility, and surface properties, enabling applications ranging from apparel to technical textiles [28,33,44].

Sheet and film formation enables the production of leather-like or plastic-like materials from agricultural pulps [11,18,45]. Residues from apples, mangoes, and grapes have been processed into flexible films and sheets with aesthetic and mechanical properties suitable for fashion accessories, footwear, and interior design applications [1,11,18,45]. These materials are typically produced through casting, compression, or coating techniques, often combined with plasticizers or bio-based binders to improve flexibility and durability [26,45]. Such bio-based alternatives offer biodegradable and cruelty-free solutions that address environmental and ethical concerns associated with conventional leather and plastics [3,26,46].

Composite materials represent a key pathway for converting agricultural residues into high-performance textile-compatible materials [41,43]. In such systems, agro-derived fibers or particulates are incorporated as reinforcements within biodegradable polymer matrices, enabling the development of materials with tailored mechanical, thermal, and functional properties [47]. Common biodegradable matrices include polylactic acid (PLA), polyhydroxyalkanoates (PHA), starch-based polymers, and polybutylene succinate (PBS), which offer different balances between biodegradability, processability, and mechanical performance [47,48].

A wide range of agricultural residues, including rice husk, wheat straw, sugarcane bagasse, coconut shell, and fruit-derived particulates, have been extensively investigated as reinforcing phases [11,17,43]. These materials contribute to improved stiffness, reduced density, and lower production costs, while simultaneously promoting the valorization of agricultural waste streams [47,48]. Beyond fibrous reinforcements, particulate agro-waste such as fruit peels, nutshells, and agro-industrial powders has also been shown to modify composite properties, including thermal stability and biodegradability, expanding the design space of sustainable materials [11,17].

The incorporation of lignocellulosic residues into polymer matrices has been shown to significantly influence mechanical properties, depending on fiber loading, dispersion, and interfacial adhesion [47]. For instance, starch-based composites reinforced with natural fibers can exhibit enhanced tensile strength and modulus due to effective stress transfer between matrix and reinforcement, although excessive filler content may lead to agglomeration and reduced performance [48]. Similarly, agro-residues such as rice husk, bagasse, and coconut shell have demonstrated improved mechanical and tribological properties when incorporated into polymer matrices, highlighting their potential as functional reinforcements rather than inert fillers [11,48].

The performance of such biocomposites is strongly governed by interfacial adhesion between hydrophilic natural fibers and typically hydrophobic polymer matrices [49]. This inherent incompatibility often limits stress transfer efficiency and long-term durability [50]. To address this challenge, surface modification techniques, including alkali treatment, silane coupling, acetylation, and enzymatic functionalization, are widely applied to improve fiber–matrix compatibility, reduce moisture sensitivity, and enhance interfacial bonding [50,51].

Hybrid composites, which combine agricultural residues with either synthetic fibers (e.g., glass or polyester) or other natural fibers (e.g., flax, hemp, jute), have emerged as an effective strategy to overcome the limitations of single-fiber systems [52]. Natural–synthetic hybrid systems can significantly improve tensile strength, impact resistance, and durability, while natural–natural hybrids enhance biodegradability and reduce environmental impact [49,52]. For example, hybrid composites incorporating multiple agro-waste particulates such as bagasse, rice husk, and coconut shell have demonstrated synergistic improvements in mechanical and wear properties due to optimized reinforcement interactions [53].

Recent literature highlights that hybridization strategies enable optimization of strength-to-weight ratios, dimensional stability, and moisture resistance, making these materials suitable for demanding applications in automotive, construction, and technical textiles [11,52,53]. Moreover, the development of agro-waste-based hybrid biocomposites aligns with circular economy principles by integrating multiple waste streams into high-value materials and supporting sustainable material innovation pathways [54]. The growing body of research demonstrates that the careful selection of matrix systems, reinforcement types, and hybridization strategies is essential for optimizing the performance and sustainability of bio-based composites derived from agricultural residues [47,52,54].

4.4. Textile Properties Enhancement

To meet application-specific performance requirements, biotextiles often undergo post-processing and functionalization.

Cross-linking agents, such as citric acid and selected isocyanates, enhance mechanical strength, dimensional stability, and wrinkle resistance by forming chemical bonds between polymer chains [55,56]. These treatments are particularly important for ensuring durability in apparel and technical textiles [32,33,55,56].

Bio-coatings derived from natural polymers offer environmentally friendly performance enhancements [33]. Chitosan provides antimicrobial activity and improved dye affinity, while lignin-based coatings function as natural UV stabilizers or flame retardants [19]. These approaches reduce dependence on synthetic chemical finishes and improve biodegradability [10].

Blending with biodegradable polymers, including PLA and PHAs, further improves processability, elasticity, and mechanical performance [14,57]. Hybrid materials combining agricultural fibers with biodegradable matrices exhibit properties suitable for demanding textile and technical applications while maintaining reduced environmental footprints [4].

In addition to these approaches, the enhancement of biotextile performance is closely related to modifications at the fiber surface and microstructural level [49,50,57]. Improvements in tensile strength, flexibility, barrier properties, and durability are often achieved through controlled interfacial interactions, crystallinity adjustments, and incorporation of nano-scale reinforcements such as nanocellulose [35,41,57]. These modifications influence moisture absorption, thermal stability, and resistance to mechanical stress, which are critical parameters for textile applications [47,52]. As highlighted in the literature, the effectiveness of these strategies depends on the compatibility between treatment methods, polymer structure, and intended end-use performance requirements [50,54].

4.5. Research Gaps and Technological Bottlenecks

Despite substantial progress in residue-based biomaterial research, several structural and technological gaps remain unresolved. First, there is limited availability of pilot-scale validation studies bridging laboratory extraction protocols with industrial-scale fiber spinning and composite manufacturing [6,15,28]. Most published work focuses on material characterization rather than continuous-process integration, creating uncertainty regarding scalability and process stability. Second, pretreatment optimization remains insufficiently standardized. Comparative studies evaluating alkaline, organosolv, enzymatic, and hybrid pretreatments under harmonized system boundaries are scarce, leading to fragmented techno-economic conclusions [29,32,36]. This limits cross-study comparability and industrial decision-making.

Third, polymer purity and reproducibility remain critical bottlenecks. Variability in lignin and hemicellulose content across seasonal and regional biomass streams affects downstream spinning performance and mechanical consistency of regenerated fibers [31,35]. Advanced fractionation control and feedstock characterization protocols are therefore required. Fourth, environmental performance data are often reported under differing LCA boundaries, allocation methods, and impact categories, hindering robust benchmarking [10]. Greater harmonization of Life Cycle Inventory (LCI) datasets and sensitivity-based scenario modeling is necessary to support investment-grade sustainability claims. Finally, limited integration between digital monitoring systems and bio-based production processes constrains supply chain traceability and feedstock optimization, particularly in decentralized models.

Addressing these gaps requires: (i) pilot-scale demonstration plants co-located with agricultural hubs; (ii) standardized techno-economic comparison of pretreatment routes; (iii) AI-assisted feedstock quality monitoring; and (iv) harmonized LCA frameworks aligned with ISO standards [26,54]. Recent advances in agro-waste valorization pathways and circular textile systems provide methodological foundations for such integration strategies [11,15].

In this context, Figure 3 illustrates the closed-loop lifecycle of agricultural residue valorization, showing how fruit and nut waste streams are transformed into biotextiles and ultimately reintegrated into natural systems at end-of-life (EoL). This model emphasizes resource efficiency, cascading use of biomass, and alignment with circular bioeconomy principles by ensuring that materials return safely to the biosphere after use.

To synthesize the technological pathways, environmental performance indicators, and maturity levels reported across the reviewed literature,

Table 3. Comparative Overview of Agricultural Residue Valorization Pathways for Biotextile Applications.

Biomass Type	Main Polymer Target	Pretreatment Route	Typical Yield (%)	Reported TRL	LCA Advantage	Representative Sources
Grape pomace	Cellulose/polyphenols	Alkaline pulping + bleaching	35–50	4–6	70–80% lower GHG vs. polyester	[13,15]
Citrus peels	Cellulose/pectin	Acid extraction + pulping	30–45	6–8	80–95% lower water use vs. cotton	[12,37]
Olive pomace	Cellulose/lignin	Organosolv/alkaline	25–40	3–5	Reduced land-use intensity due to secondary biomass sourcing	[28,36]
Nut shells	Lignin/reinforcement fibers	Mechanical + alkaline treatment	20–35	4–6	Lower embodied energy in composite applications	[6,16,45]
Banana pseudostem	Cellulose fibers	Mechanical + enzymatic extraction	40–60	5–7	Reduced cumulative energy demand compared with synthetic fibers	[14,26]
Peach processing waste (pomace & peel)	Dissolving-grade cellulose	NaOH + organic acids + H2O2 bleaching	9.7–12.3	4–5	Avoided upstream cultivation burden; waste valorization benefit	[18]

provides a structured comparative overview of representative agricultural residue valorization routes for biotextile applications. The table consolidates biomass type, target polymers, pretreatment approaches, indicative yield ranges, reported technological readiness levels (TRLs), and principal environmental advantages as documented in recent studies.

This structured comparison enables cross-study benchmarking and highlights differences in scalability and sustainability performance. Reported values are indicative and depend on feedstock composition, pretreatment intensity, process configuration, and system boundaries applied in individual studies. TRL estimates reflect synthesis of literature published between 2021 and 2025 and should be interpreted as approximate maturity ranges rather than standardized industrial classifications.

Notably, the inclusion of peach-processing residues demonstrates the technical feasibility of producing dissolving-grade cellulose pulp with α-cellulose content and crystallinity comparable to commercial textile pulps, highlighting the emerging industrial potential of Mediterranean fruit-processing waste streams [18].

Overall, while the reviewed literature indicates that multiple residue-to-material pathways demonstrate promising laboratory-scale performance, their transition to industrial implementation remains constrained by variability in feedstock quality, process integration challenges, and limited pilot-scale validation [6,27,29,54]. Consequently, Table 3 should be interpreted not only as a comparison of material pathways but also as an indicator of technological readiness and scale-up potential across different valorization routes.

5. Economic Impact Assessment and Market Opportunities

The literature indicates that the economic viability and market potential of valorizing fruit and nut agricultural residues into biomaterials and biotextiles are increasingly recognized as strong drivers for industrial uptake, particularly when residue streams are treated as strategic, low-cost feedstocks within integrated regional supply chains [11,15]. In parallel, policy frameworks that incentivize circular bioeconomy transitions, together with brand-level sustainability commitments, are accelerating demand for bio-based alternatives and creating clearer market pull for residue-derived materials [22].

5.1. Cost and Value Chain Integration

One of the most compelling economic advantages of utilizing agricultural residues is the reduction in raw material and feedstock procurement costs, because residues are generated as by-products and can often be sourced locally with limited land- and input-related cost burdens compared with dedicated fiber crops [5,6]. In practical terms, this can translate into substantial savings along the value chain, and multiple techno-economic and sectoral assessments indicate that cost reductions can reach up to ~60% under favorable sourcing and preprocessing conditions compared with conventional synthetic or virgin natural-fiber routes [11,15].

Beyond feedstock pricing, strategic co-location of agri-processing facilities with preprocessing and textile-material conversion units can improve profitability by lowering transportation costs, reducing handling losses, and stabilizing supply logistics, particularly for moist residues (e.g., pomace) that are costly to transport over long distances [11,23]. Such localized value-chain architectures are also associated with lower logistics-related emissions and can support rural employment, supplier diversification, and stronger regional industrial resilience, key objectives aligned with circular economy policy directions in the EU [22].

However, economic performance varies substantially depending on the selected pretreatment route. Mechanical preprocessing, such as grinding, drying and milling involves relatively low capital and operational expenditure but may yield lower polymer purity, often requiring additional downstream chemical refinement [6,14]. In contrast, alkaline and acid pretreatments achieve higher cellulose recovery efficiencies but involve chemical procurement, effluent treatment infrastructure, and corrosion-resistant processing equipment, thereby increasing operational costs and environmental management requirements [29,31].

Organosolv technologies offer improved lignin valorization and solvent recovery potential, enhancing co-product revenue streams, yet their higher capital intensity may constrain small- and medium-scale adoption [36]. Enzymatic pretreatments present lower environmental burdens and reduced chemical inputs; however, enzyme costs and longer reaction times may limit short-term economic competitiveness under current market conditions [20,32].

Comparative techno-economic assessments suggest that hybrid mechanical-alkaline systems often provide balanced cost-performance outcomes when integrated with cascading valorization of co-products such as pectin and polyphenols, improving overall value-chain resilience [15,17]. Future Greek pilot initiatives should therefore incorporate sensitivity-based cost modelling and LCA-informed allocation analysis to determine region-specific optimal pretreatment pathways.

5.2. Global Market Trends

Market dynamics further reinforce the strategic importance of this sector. The global biomaterials market was valued at USD $64.9 billion in 2020 and is projected to exceed USD 212.4 billion by 2030, indicating strong growth expectations that can stimulate investment into bio-based fiber, film, and composite value chains [8]. Within this broader expansion, biotextiles are positioned to capture a growing share as sustainability requirements intensify in fashion, packaging, and mobility-related sectors (e.g., automotive interiors), where renewable and lower-impact material inputs are increasingly prioritized [8,22].

Policy and funding instruments in Europe are also shaping the innovation landscape. The Circular Bio-based Europe Joint Undertaking (CBE JU) functions as a public–private partnership under Horizon Europe to support the scale-up and deployment of competitive bio-based industries, directly strengthening the financing environment for circular bioeconomy solutions (including bio-based textiles and materials) [58].

In parallel, corporate actions signal stronger demand-side commitments to alternative and lower-impact material sourcing. For example, recent industry reporting highlights major brand engagement with next-generation cellulose-based material strategies and multi-year agreements intended to reduce reliance on virgin feedstocks, reflecting the broader shift toward circular and bio-based supply chains (examples Stella McCartney and H&M Conscious) [59,60]. Wider cross-brand initiatives and public sustainability commitments, reinforced through multi-stakeholder fashion-climate programs, also indicate that the adoption of alternative materials is increasingly treated as a structural transition rather than a niche trend [61].

5.3. Potential for Greece

The literature suggests that Greece is well positioned to translate residue availability into bio-industrial activity due to its high and geographically concentrated production of olives and grapes, which generate substantial volumes of process residues suitable for biomaterial and biotextile conversion [24]. Scenario-based estimates reported in the literature suggest that, under assumptions such as the valorization of approximately 20% of annual olive pomace and grape pomace streams, Greece could potentially generate around 5000 jobs (particularly in rural regions) and contribute up to EUR 150 million per year in bio-industrial output [62].

Such estimates are based on assumed configurations of decentralized preprocessing units combined with medium-scale fiber regeneration facilities (5000–10,000 t/year capacity). Comparable European pilot-scale bio-based material clusters reported in the literature indicate that employment multipliers may increase when feedstock preprocessing, polymer extraction, and product fabrication are co-located within regional innovation hubs [11,22].

Enterprise-cooperative partnership models, supported by EU bioeconomy instruments such as the Circular Bio-based Europe Joint Undertaking (CBE JU), have been discussed in the literature as a potential framework for Greece to transition from low-value biomass disposal toward higher-value textile-grade cellulose production [46]. Nevertheless, detailed techno-economic modelling specific to Greek agricultural clusters remains necessary to validate job multipliers and value-added distribution under varying feedstock allocation scenarios.

Critically, the feasibility of these opportunities depends on several factors highlighted in the literature, including (i) decentralized preprocessing near feedstock sources (to reduce logistics burdens), (ii) technology pathways aligned with scalable cellulose/fiber and film/composite production routes, and (iii) enabling policy mechanisms that de-risk investment and stimulate demand through circular procurement and innovation funding [11,22].

6. Environmental Sustainability and LCA

The environmental advantages of producing biomaterials and biotextiles from fruit and nut agricultural residues have been widely reported in the literature and are commonly assessed using LCA approaches. LCA is a standardized methodological framework (ISO 14040/14044) [63] that quantifies environmental impacts across the entire life cycle of a product, encompassing raw material sourcing, processing, manufacturing, use, and EoL stages [64,65]. Applying LCA to biotextiles enables a transparent comparison with conventional textile materials, such as polyester and cotton, and provides a robust scientific basis for assessing sustainability performance within a circular bioeconomy context.

A growing body of literature demonstrates that residue-derived biotextiles consistently outperform conventional textiles across key environmental indicators, including water consumption, greenhouse gas (GHG) emissions, land-use intensity, and EoL performance [10,27,45,64,66]. These benefits arise primarily from the use of secondary biomass streams that do not require dedicated cultivation, irrigation, or land conversion, thereby avoiding upstream environmental burdens associated with fiber crop production and fossil-based polymer synthesis.

Table 4. Life Cycle Assessment Comparison of Conventional Textiles and Biotextiles (reported values are indicative and depend on feedstock type, system boundaries, and processing routes).

Indicator	Polyester	Cotton	Biotextile
Water Use (L/kg)	~60	~10,000	~500
CO2 Emissions (kg)	~9.5	~5.4	~1.6
Land Use (m2/kg)	~0.3	~2.6	~0.1
Biodegradability	No	Yes	Yes

summarizes LCA-based performance metrics comparing conventional textiles with biotextiles derived from agricultural residues, based on values reported across different studies and considering cradle-to-gate or cradle-to-grave system boundaries. Although absolute values vary depending on feedstock type, processing route, and system boundaries, the literature generally indicates similar trends across multiple LCA studies.

6.1. Water Footprint Reduction

One of the most significant environmental benefits of biotextiles derived from fruit and nut residues is their markedly reduced water footprint. Conventional cotton cultivation is among the most water-intensive agricultural activities, requiring up to 10,000 L of water per kilogram of fiber, largely due to irrigation demands [10,67]. In contrast, residue-based biotextiles eliminate agricultural water inputs entirely, as feedstocks are generated as by-products of food production [68].

Water use in biotextile systems is primarily associated with preprocessing, extraction, and material conversion steps, resulting in typical values around 400–600 L/kg of material [27,45,67]. This represents a reduction of up to 95% compared with cotton-based textiles, making residue-derived biotextiles particularly attractive for deployment in water-scarce regions and under increasingly restrictive water-management policies [67,68].

6.2. Greenhouse Gas Emissions and Energy Demand

Synthetic fibers such as polyester exhibit high GHG emissions due to their reliance on fossil-based feedstocks and energy-intensive polymerization processes, with cradle-to-gate emissions commonly exceeding 9 kg CO₂-eq/kg of fiber [10,64]. Cotton textiles, although bio-based, also incur substantial emissions associated with fertilizer application, irrigation, and land management practices. In contrast, LCA studies consistently report significantly lower GHG emissions for agricultural-residue-based biotextiles, typically below 2 kg CO₂-eq/kg [27,30,64,66].

As summarized in Table 4, biotextiles exhibit emissions of around 1.6 kg CO₂/kg, corresponding to a reduction of approximately 70–80% relative to conventional synthetic fibers. These reductions are primarily attributed to the use of renewable biomass feedstocks and less energy-intensive processing routes, and they are further enhanced when decentralized or regionally integrated processing models are applied, reducing transportation-related emissions and supporting localized circular value chains [10,27,34,66,69]. Such emission reductions contribute directly to climate change mitigation objectives and the transition toward lower-carbon textile production systems.

6.3. Land Use and Circular Resource Efficiency

A critical environmental advantage of residue-based biotextiles is the absence of additional land-use requirements [70]. Unlike cotton and other fiber crops cultivated specifically for textile production, biotextiles derived from fruit and nut residues utilize waste streams generated by existing agricultural systems, thereby avoiding land expansion, deforestation, and indirect land-use change [22,45,71]. This benefit is quantitatively reflected in Table 4, where land-use intensity for biotextiles (0.1 m²/kg) is substantially lower than that of cotton (2.6 m²/kg), highlighting the land-efficiency of residue-based feedstocks.

From a circular economy perspective, this approach exemplifies cascading biomass utilization, in which food production remains the primary function of agricultural systems while material valorization occurs as a secondary, high-value pathway [4,22,72]. LCA-based ecodesign studies further demonstrate that such strategies enhance overall resource efficiency and minimize environmental trade-offs across the life cycle, supporting sustainable land-use management and circular bioeconomy objectives [59,73].

6.4. End-of-Life Performance and Biodegradability

EoL considerations are increasingly recognized as a critical component of textile sustainability. Conventional synthetic textiles contribute to persistent waste streams and microplastic pollution, while even natural fibers may be problematic if blended with non-biodegradable components [74,75].

Biotextiles derived from lignocellulosic agricultural residues exhibit inherently favorable EoL characteristics, including biodegradability and compatibility with composting or biological treatment routes, provided that auxiliary additives and coatings are appropriately selected [76,77]. Recent LCA and EoL assessments highlight that integrating ecodesign principles, such as mono-material construction, biodegradable finishes, and avoidance of toxic auxiliaries, can further enhance circularity and reduce downstream environmental burdens [78,79].

7. Internet of Things (IoT) Market Overview and Relevance to Biomaterials

The rapid expansion of the Internet of Things (IoT) is transforming industrial systems by enabling real-time data acquisition, connectivity, and intelligent decision-making across complex value chains. Within the context of sustainable biomaterials and biotextiles, IoT technologies are discussed in the literature as offering opportunities to enhance material traceability, process efficiency, resource optimization, and circularity [80]. The integration of IoT systems is increasingly recognized as a potential enabler for scaling bio-based material systems while maintaining transparency and environmental performance, particularly in decentralized biomass value chains [80].

7.1. Global IoT Market Trends

The global IoT market is undergoing rapid expansion, driven by advances in connectivity, cloud computing, data analytics, and the increasing deployment of connected devices across industrial and consumer applications [81]. Recent market assessments highlight both the scale and the growth dynamics of IoT, underscoring its relevance for digitally enabled and sustainability-oriented sectors such as biomaterials and biotextiles [82].

Quantitative estimates from market intelligence sources (

Table 5. IoT Market Size Forecasts from Various Sources. Data compiled from Statista [39] and Fortune Business Insights [44].

Source	Year	Market Size (USD Billion)
Statista	2025	1060
Statista (Projected)	2029	1560
Fortune Business Insights	2023	595.73
Fortune Business Insights (Projected)	2024	714.48
Fortune Business Insights (Projected)	2032	4062.34

) illustrate the scale of IoT deployment. These projections provide contextual background on the technological landscape within which bio-based material systems may evolve, rather than representing a direct analysis of the biomaterials sector. Industrial IoT (IIoT) applications are particularly relevant for manufacturing, logistics, and process industries, where similar monitoring and optimization functions may be applied to biomass processing and material production systems.

Table 5 presents indicative IoT market size forecasts derived from different sources, highlighting both the magnitude of the global IoT market and the variability in projections due to methodological differences. While these values reflect general digitalization trends, their relevance in this study lies in illustrating the technological environment supporting traceability, monitoring, and process optimization in emerging bio-based value chains.

7.2. Relevance of IoT to Biomaterials and Biotextiles

The convergence of IoT technologies with biomaterials and biotextiles introduces new functional and operational possibilities across the life cycle of bio-based products, from agricultural residue sourcing to manufacturing, use, and EoL management [80,82,83]. In this context, IoT is primarily relevant as a supporting tool for monitoring, traceability, and system optimization within biomass-based value chains [80,84].

Smart and Functional Biotextiles. IoT-enabled sensors can be integrated into biotextiles to create smart materials capable of monitoring environmental conditions, mechanical stress, or physiological parameters [81,83]. Such applications are particularly relevant for healthcare, sports, and protective textiles, where bio-based fibers can be combined with embedded sensing elements to deliver functionality while maintaining reduced environmental footprints [83].

Supply Chain Traceability and Transparency. IoT systems enable monitoring of temperature, humidity, location, and handling conditions during the collection, transport, and processing of agricultural residues and biomaterials [82,84]. When combined with digital platforms, these systems support traceability, quality control, and verification of sustainability claims across bio-based value chains [84,85].

Precision Agriculture and Residue Optimization. IoT-enabled precision agriculture systems allow monitoring of soil moisture, nutrient availability, and crop health, supporting improved agricultural practices and more consistent residue quality [82,86]. These capabilities may contribute to more stable biomass supply streams for biomaterial production without increasing resource inputs [86].

Waste Management and Circularity. IoT applications extend to waste collection, sorting, and recycling systems, supporting more efficient management of agricultural residues and post-consumer biotextile waste [80,87]. Sensor-based sorting and data-driven logistics can improve recovery rates and facilitate circular material flows [87].

Overall, the literature suggests that IoT technologies can support improved process control, transparency, and resource efficiency in bio-based material systems [80,82,84]. However, their implementation remains context-dependent and may be influenced by infrastructure availability, data integration challenges, and investment requirements [82,85].

8. Acceptability of Environmentally Friendly Materials

Growing consumer awareness of environmental degradation, climate change, and ethical production practices has significantly increased demand for sustainable and eco-friendly materials across the textile and fashion sectors [88,89]. Empirical studies consistently report positive consumer perceptions toward environmentally friendly textiles, particularly when sustainability attributes are clearly communicated and verified. Compared to conventional products, sustainable textiles are associated with higher perceived quality, enhanced product value, stronger purchase intention, and increased likelihood of repurchase [90].

The use of sustainable materials has emerged as a decisive purchasing criterion for a substantial share of consumers, alongside traditional factors such as price, durability, and aesthetics [91]. This shift is particularly pronounced among younger and environmentally conscious demographics, reflecting broader societal transitions toward responsible consumption patterns. As a result, brands increasingly recognize sustainability not only as an ethical imperative but also as a source of competitive advantage.

Despite this positive trajectory, several barriers continue to hinder widespread adoption. These include higher production costs, supply chain complexity, limited economies of scale, and persistent misconceptions regarding the performance, durability, and comfort of bio-based textiles [92]. However, ongoing advances in material science, improved processing efficiency, and strengthening regulatory frameworks are progressively mitigating these challenges. Major brands are actively investing in sustainable material portfolios, including organic fibers, recycled polymers, and bio-based alternatives, to reduce environmental impacts while responding to evolving consumer expectations [93,94,95].

9. Policy Recommendations and Strategic Roadmap for Greece

To fully harness Greece’s potential within the emerging biomaterials and biotextiles sector, coordinated policy action, targeted research investment, and active stakeholder engagement are essential. The following strategic recommendations outline a roadmap for integrating agricultural residue valorization into national circular bioeconomy objectives.

9.1. Incentivizing Circular Bioeconomy Hubs

The establishment of regional circular bioeconomy hubs represents a cornerstone for localized value creation and industrial scaling. Such hubs would function as integrated centers for residue collection, preprocessing, biofabrication, and material development.

Regional biofabrication centers. Strategic placement in high-production areas such as the Peloponnese (citrus and olives), Crete (grapes, olives, figs), and Thessaly (almonds and other crops) would reduce transportation requirements, lower emissions, and strengthen rural economies [96].

EU and national funding mechanisms. Leveraging European Green Deal instruments, the Circular Bio-based Europe Joint Undertaking (CBE JU), and National Strategic Reference Framework (NSRF) programs can provide essential financial support for infrastructure, technology deployment, and workforce development [58,97].

9.2. Regulatory and R&D Support

A supportive regulatory environment, combined with robust research and development infrastructure, is critical for overcoming technological, economic, and market barriers.

Fiscal incentives for biomaterial SMEs. Targeted tax reductions and subsidies for small and medium-sized enterprises can stimulate innovation, reduce financial risk, and accelerate market entry for bio-based products [98].

National R&D platforms. Dedicated research platforms focused on biopolymer extraction, material characterization, scale-up validation, and standardized testing would foster collaboration between academia, industry, and government, strengthening Greece’s innovation capacity [99].

Importantly, policy design must also explicitly address long-term EoL management of emerging bio-based materials. Experience from other rapidly expanding renewable technology sectors demonstrates that insufficient early stage planning can lead to substantial downstream waste management challenges. For example, projections of photovoltaic panel waste volumes in the European Union highlight the urgency of proactive regulatory frameworks, recycling infrastructure development, and circular design integration well before large-scale deployment occurs [100]. Incorporating similar foresight into biomaterials and biotextiles policy can help prevent future waste bottlenecks and ensure that circular bioeconomy objectives are achieved in practice.

9.3. Farmer and Cooperative Engagement

Active participation of agricultural stakeholders is fundamental for securing reliable feedstock streams and ensuring equitable value distribution.

Valorization contracts with cooperatives. Formal agreements for residue collection and preprocessing can generate additional income streams for farmers while promoting sustainable waste management practices [101].

Training and decentralized valorization units. Supporting modular, small-scale biowaste valorization units at the cooperative or farm level can reduce logistical burdens, enable decentralized processing, and stimulate local entrepreneurship [102,103].

10. Conclusions

The reviewed literature suggests that fruit and nut agricultural residues represent a strategically important and environmentally advantageous feedstock for the production of advanced biomaterials and biotextiles. Their valorization contributes to reduced greenhouse gas emissions, lower water and land-use pressures, and improved end-of-life performance, while simultaneously generating economic diversification and rural development opportunities. The available evidence indicates that although Greece possesses substantial agricultural residue availability and strong alignment with European circular economy policy frameworks, it remains structurally behind leading European bioeconomy adopters such as Italy and Spain, where residue-based textile materials have already reached commercial scale. The Greek bio-based textile sector is currently characterized by research activity rather than industrial consolidation, with limited biorefinery-scale infrastructure, insufficient public–private integration, and absence of coordinated certification and investment mechanisms. Bridging this gap requires systemic coordination rather than isolated technological advances. Transitioning from biomass availability to competitive circular material production depends on infrastructure development, cluster formation, industrial symbiosis, and integration with European innovation platforms. With targeted strategic planning and policy coherence, Greece has the capacity to evolve from a biomass-rich but under-industralized residue management model toward a resilient, competitive, and sustainability-oriented circular bioeconomy framework.

11. Limitations

This study is based primarily on secondary data sources, published LCA results, and reported techno-economic indicators. Although harmonization criteria were applied during literature screening, differences in system boundaries, allocation methods, functional units, and impact categories across the reviewed LCA studies may affect direct quantitative comparability. Reported environmental performance values should therefore be interpreted as indicative ranges rather than absolute benchmarks. The residue availability assessment relies on aggregated national and regional agricultural production statistics. Seasonal variability, moisture content fluctuations, competing biomass uses such as energy recovery and animal feed, and collection inefficiencies were not modeled dynamically. As a result, effective industrially available biomass volumes may differ from theoretical estimates. The circular system representation presented (Figure 3) is conceptual and does not include quantified material flow analysis (MFA) or life cycle inventory (LCI) datasets. Integration of dynamic MFA-LCA coupling would strengthen future system-level assessments. Finally, while IoT integration pathways and digital traceability frameworks are discussed as enabling mechanisms, their practical implementation challenges, data governance implications, and cybersecurity dimensions were not evaluated in depth. These aspects warrant further interdisciplinary investigation.

12. Future Research Directions

Realizing the full valorization potential of Greek agricultural residues requires targeted research and coordinated innovation strategies. Priority should be given to the optimization and industrial scaling of enzymatic and microbial extraction technologies to improve efficiency, reduce processing costs, and enhance robustness under region-specific biomass conditions. Equally important is the development of harmonized standards and certification schemes for residue-derived biomaterials, ensuring market credibility, facilitating international competitiveness, and strengthening consumer trust in bio-based textile applications. Comprehensive techno-economic and LCAs of decentralized residue-processing systems are also required. Future studies should prioritize process-scale validation at TRL 5–7, implement harmonized cradle-to-grave LCA methodologies with allocation sensitivity analysis, and conduct comparative techno-economic modeling of alternative pretreatment routes. Furthermore, the integration of digital traceability systems within decentralized valorization clusters could enhance transparency, supply chain optimization, and regulatory compliance. Addressing these analytical and structural gaps will be essential for enabling Greece to transition toward a coordinated circular bioeconomy model grounded in technological maturity, environmental performance, and market viability.