Green Starches: Phytochemical Modification and Its Industrial Applications—A Review

Abstract

Green starches, sourced from sustainable and unconventional plant and protist sources, are gaining prominence in functional ingredient research due to their combined technological and bioactive properties. Within the context of circular economy and green chemistry, this review addresses the extraction processes of native, modified, and phytochemically enriched starches. It highlights diverse applications, focusing on the advantages of phytochemical enrichment over other modification methods, given the acquired properties from bioactive compound incorporation. Initially, the review approaches the circular economy and green chemistry’s contributions. Various starch modification processes are presented, emphasizing chemical alterations and their impacts on food safety and the environment. Recent studies employing this principle are detailed, focusing on food applications, extending to pharmaceuticals, cosmetics, and culminating in bioelectronics. Finally, new research ideas are proposed, aiming to inspire further studies in the field. This review underscores a significant and growing interest in sustainable starch applications, particularly biocompound-enriched starches, across diverse sectors like pharmaceuticals, agriculture, textiles, and packaging. This trend is driven by the need for safer, eco-friendlier alternatives, with emerging fields such as bioelectronics and 3D/4D printing also recognizing starch’s versatile potential.

1. Introduction

Carbohydrates are complex starches found in various organisms within the plant and protist kingdoms that provide energy for several physiological functions in the body. A relatively high intake of complex carbohydrates and a limited intake of added or free sugars are generally recommended for a healthy diet [1,2].

Starch is a natural, biodegradable, and renewable polysaccharide, mainly extracted from cereals, legumes, tubers, and storage roots, standing out for its availability and characteristics of industrial interest [3,4]. Starch occurs as granules of various sizes and types, each with unique properties. Amylose and amylopectin are the main components of these granules, directly influencing their physical and chemical characteristics [5]. It is widely used in both the food industry and other industries to maintain quality characteristics, improve texture, and act as a thickening agent, among other functions [6]. However, understanding the properties of starch is fundamental for selecting the most suitable type for different applications.

Native starches have limited applications, which hinders their industrial use, often requiring modification to enhance positive characteristics and eliminate their limitations. However, the applications of native starch are restricted due to its insolubility in cooled water, a tendency to undergo significant retrogradation and syneresis, limited shear resistance, and susceptibility to thermal decomposition. These inherent limitations compromise its applicability in various products, including frozen goods, sauces, dairy desserts, and biodegradable packaging [7,8].

The choice of starch source and the application of modification processes allow for adjusting the functional properties of starch to the specific needs of each application [9].

Particularly, phytochemical enrichment is emerging as an area of growing interest, seeking safer alternatives with a lower environmental impact compared to certain chemical modifications. This review will explore the applications of phytochemically enriched starch in sectors such as food, pharmaceuticals, and cosmetics, culminating in its potential in bioelectronics, and will propose future research directions to drive sustainable innovations.

2. Starch Modification Processes, Benefits, and Uncertainties

Starch modification processes, commonly categorized as chemical, enzymatic, physical, and hybrid, primarily target key physiological and functional properties to meet technological demands [10]. These modifications aim to control: gelatinization, the transition of starch granules from an ordered to a disordered structure upon heating with sufficient water; retrogradation, the re-formation of hydrogen bonds and subsequent recrystallization of amylose and amylopectin molecules after gelatinization and cooling, often leading to gel formation or precipitation. The amylose-to-amylopectin ratio is a critical factor influencing this process, guiding many modifications to address constituent imbalances [11]. Digestion: the enzymatic hydrolysis of starch in the human gastrointestinal tract by amylases [10].

Beyond these physiological aspects, starch modifications frequently enhance functional properties such as turbidity, water and oil absorption indices, solubility indices, hygroscopicity, swelling power, and syneresis [12,13]. Alterations in rheological and pasting properties are also common subjects of study in starch modification [14].

Chemical modification is the most widely used starch modification process, encompassing techniques such as esterification, oxidation, acetylation, sulfation, amidation, and quaternization, many of which are applied to polysaccharides for industrial uses [15]. While these transformations achieve high yields, they often present several drawbacks: the use of toxic reagents, adverse reaction conditions, by-product generation, and a lack of selectivity [16]. Conventional chemical processes also produce substantial, environmentally harmful effluents requiring extensive treatment [17]. A major concern for food applications is the mandatory labeling of chemically modified starches, which often deters consumers [18]. Furthermore, challenges include random attack at branching points during acid hydrolysis, high glucose yield, and difficulties in removing excess acid [19]. Chemically modified starches for food use must comply with strict regulations, and the disposal of generated chemical waste remains a significant challenge. Research on the potential long-term health effects of consuming these starches is also notably lacking [20].

While chemical modifications impart desirable properties to starches, their application in food necessitates careful consideration of associated potential risks. Historically, molecular manipulation of food substances has led to adverse health effects, often discovered belatedly. The inherent complexity of molecular interactions in living organisms makes predicting the long-term effects of these chemical modifications challenging, underscoring the critical need for rigorous safety testing before new foods or additives enter the market [21,22]. Novel chemical substances within a food matrix can interact unexpectedly with the human organism, potentially revealing yet-unknown health impacts in future studies [23,24]. Therefore, precaution must guide the production and consumption of these products, driving the demand for continuous and rigorous research into “clean” or “green” starch modification alternatives [25].

Enzymatic modification methods have garnered significant academic and industrial interest due to their perceived milder and safer nature compared to chemical approaches. Bangar et al. [26] highlight these methods as more selective, generating less waste, being healthier, and offering easier recovery. Depending on the enzyme choice, notable changes in starch granule crystallinity can be achieved, broadening applications [27]. Enzymes such as α-amylase, β-amylase, pullulanase, glucose isomerase, and xylanase, among others, directly alter starch properties, notably improving freeze–thaw stability of gels and retarding retrogradation during storage [28]. This enhanced stability is attributed to the formation of short-chain linear amylopectin fractions of low molecular weight, which also increases resistant starch content [29,30]. Despite these advantages, enzymatic modification remains relatively expensive, prompting proposals for its combined use with methods like physical modification [3].

Despite their benefits, enzymatic starch modifications face considerable industrial challenges. Shokri et al. [31] highlight these limitations, noting that they demand rigorous control of pH and temperature, incur high costs, and often result in a slowly and poorly hydrolyzed product due to the native starch’s semicrystalline structure. They also point out challenges related to the use of different enzyme types in conjunction for more satisfactory results, poor stability concerning temperature, pH, and solvents, as well as inadequacy in enzyme separation and reuse. According to Compart et al. [5], the time-consuming nature of these methods hinders their widespread adoption. Moreover, they emphasized that natural enzymes, despite their availability, often exhibit structural instability and low catalytic efficiency due to biological constraints. Thus, improving industrially important enzyme properties or integrating enzymatic approaches with other modification methods is crucial.

Physical modification methods are recognized for being safe, cost-effective, and efficient, categorized into thermal and non-thermal treatments [30,32]. Thermal methods, including heat, moisture, and annealing treatments, impact starch’s structural parameters and its physical and functional properties, such as crystallinity, morphology, solubility, viscosity, swelling capacity, pasting, gelatinization, and thermal/freeze–thaw stability [33]. Non-thermal physical modifications (e.g., micronization, non-thermal plasma, high pressure, ultrasonication, pulsed electric field, gamma irradiation) can significantly alter starch granule morphology, decrease crystallinity, and depolymerize molecular chains. These structural changes often result in increased solubility and swelling power, reduced gelatinization temperatures and viscosity, and variable in vitro digestibility, all highly dependent on starch type and treatment conditions [34,35].

A Comparative Overview of Major Starch Modifications: Processes, Attributes, and Applications is shown in Figure 1.

When examining starch modification methods, chemical, enzymatic, physical, and phytochemical, it becomes clear that while each offers unique benefits, none are universally perfect. Chemical modifications, despite their efficiency and scalability, raise concerns regarding toxicity, by-products, and environmental impact. Conversely, enzymatic and physical methods, being safer and more eco-friendly, can face limitations in their extent or cost. Phytochemical approaches, while promising and sustainable, are still largely in the exploration phase.

In this scenario, research is increasingly moving towards combined modification methods. This synergistic approach allows us to overcome the weaknesses of one method by leveraging the strengths of another, thereby optimizing starch properties and pursuing greater sustainability. For instance, a physical pretreatment might prepare starch for enzymatic action, or a milder chemical process could be refined with subsequent physical treatment. This flexibility, which enables starch customization while minimizing risks and costs, marks a significant advance. It represents a promising pathway for developing high-value modified starches that meet growing demands for safety and environmental responsibility.

3. Circular Economy and Green Chemistry

With the advent of green chemistry, alternative methods to the chemical modification of starches should be sought [36]. Given this observation, some concepts need to be clarified.

A circular economy is one that stands out for encouraging the adoption of closed-loop production methods with the aim of improving resource use efficiency, modifying processes, and increasing the lifespan of products and materials. The concept of circularity, sustainable production goals, waste and by-product cycles, and fundamental new insights should drive the investigation of unconventional starch sources as part of the circular economy [37,38]. According to Ncube et al. [39], green chemistry provides the basis for safe and sustainable circular economy practices.

According to the United States Environmental Protection Agency (EPA), green chemistry is the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances and applies across the life cycle of a chemical product, including its design, manufacture, use, and ultimate disposal. The principles of green chemistry were developed by Paul Anastas and John Warner and focus on the development of more environmentally friendly chemical processes or products. These principles aim at preventing pollution before it can occur by minimizing the use of hazardous chemicals [40]. The 12 Principles of Green Chemistry are demonstrated in Figure 2.

According to Verma et al. [41], control engineering has incorporated the ideas of green chemistry in recent years by using sustainable strategies, different techniques, and bio-based materials, including plant extracts, natural polymers, gums, waste, amino acids, and carbohydrates. Trombino et al. [42], in a study on the principles of green chemistry for the synthesis of nano- and micro-sized hydrogels intended for pharmaceutical use, reported that few studies have been conducted aiming at or exclusively employing environmentally friendly reagents to produce starch-based hydrogels. Fashi et al. [43] proposed a green modification of corn starch through repeated freeze–thaw cycles (RFTC), microwave-assisted solid-state acetic acid esterification (MSAE), and dual RFTC/MSAE treatment, obtaining the best esterification efficiency (68.7%) for combined RFTC/MSAE. Ke et al. [44] prepared a conductive composite organohydrogel based on starch/polyvinyl alcohol (PVA)/tea polyphenol (TP). According to the researchers, TP was used as a reducing and stabilizing agent to prepare antibacterial silver nanoparticles (AgNPs) due to its biocompatibility, degradability, and low cost, in addition to containing many catechol groups, which aided in the mechanical performance of the resulting organohydrogel through hydrogen bonding.

For the employment of modifications using nanoparticles to achieve widespread application, several challenges must be overcome, including colloidal stability, food compatibility, regulatory obstacles, upscaling limitations, nanotoxicity concerns, and environmental risks, in addition to difficulties in enzyme recovery and reuse after each catalytic cycle [45]. Future studies should prioritize elucidating interaction mechanisms and performing in vivo toxicological assessments. To mitigate these issues, enzymatic immobilization techniques emerge as viable alternatives, enhancing enzyme stabilization, bolstering denaturation resistance, and enabling repeated utilization [46,47].

To ascertain the increasing relevance of “Circular Economy”, “Green Chemistry”, and “Green Starch”, an online database search was performed. As depicted in the Web of Science database (Figure 3), the number of indexed research articles using the keywords “green starch” more than tripled from 277 in 2014 to 843 in 2024, signifying substantial growth in studies exploring this topic. This trend underscores a rising interest in more ecological and sustainable approaches within starch-based applications.

An analysis of the predominant publication areas concerning “green starches”, as categorized by the Web of Science database (Figure 4A), reveals that Food Science & Technology holds the leading position. This prominence reflects humanity’s primary concern with food security and the optimization of major starch commodities such as corn, potato, and cassava. Following closely, Applied Chemistry features prominently, likely driven by the corporate sector’s pursuit of enhanced products and more efficient processes, aiming for increased profitability and innovations that address demands for sustainable solutions. Polymer Science occupies the third position, highlighting the growing demand for starch applications in materials technology. This interest signals a research focus extending beyond the food sector, developing biocompounds for areas like biodegradable packaging, biomaterials, and other applications that aim for integration with living organisms and waste elimination. The prominence of Biochemistry & Molecular Biology in fourth place reflects its fundamental role in supporting these fields by investigating the biological interactions of starch and phytochemicals and providing the basis for advancements in the pharmaceutical and biotechnology industries. Finally, Chemistry, Multidisciplinary complements this scenario, evidencing that the complexity of challenges in “green starches” necessitates an integrated approach and the combined knowledge from various disciplines to drive innovation and achieve more promising results, as observed in the research on combined starch modification methods.

Among the countries’ leading publications on “green starch” (Figure 4B), China holds the largest share, reflecting its strategic national investments in sustainable technologies and circular economy initiatives. India and the United States follow, indicating significant research efforts in these major agricultural economies. Brazil also stands out among the top contributors, a position likely influenced by its vast availability of starchy raw materials and growing interest in value-added bio-products. This distribution underscores how global research leadership in green starch is increasingly shaped by national policies, resource abundance, and a drive towards sustainable industrial development.

4. Phytochemical Enrichment of Starch

Polyphenols are secondary metabolites of plant origin, classified into flavonoids, tannins, phenolic acids, and anthocyanins [48]. When incorporated into foods, along with active peptides and vitamins, these compounds confer the designation “nutraceuticals” to the products. This category encompasses foods that, in addition to their nutritional value, possess functional properties beneficial to human health, such as antioxidant, anti-inflammatory, and anticancer activities [49,50]. Studies are already being conducted on the applicability of starches modified with polyphenols in the pharmaceutical, cosmetic, packaging, and textile sectors, among others.

According to Salimi et al. [51], the physical properties of starch, such as solubility, gelatinization, and retrogradation, depend on intermolecular interactions, without altering its chemical composition or involving covalent bonds. In contrast, chemical properties result from reactions that modify the molecular structure, such as hydrolysis, oxidation, esterification, and etherification, which involve the breaking or formation of new bonds. The modification of native starch with the incorporation of polyphenols has the ability to alter its physicochemical properties. Non-covalent interactions, mainly hydrogen bonds and hydrophobic interactions, between polyphenols (anthocyanins, flavonoids, phenolic acids, and tannins) and carbohydrate polymers result in the formation of complexes that can alter the integrity of starch granules but do not necessarily modify their crystalline structure [52,53]. In this way, these modifications can influence the swelling power, solubility, and pasting of the starch. The phytochemical modification of starch, using phenolic compounds, emerges as an alternative for obtaining starches with desirable functional properties, without the need for aggressive agents and severe chemical alterations [54].

Among the most commonly employed phenolic compounds in starch modification are ferulic acid (found in rice bran), gallic acid (from coffee beans), quercetin (present in onions, grapes, and apples), caffeic acid (from coffee and fruits), resveratrol (abundant in grapes, peanuts, and berries), curcumin (derived from turmeric root), and catechin (a key component of tea leaves). These diverse phytochemicals confer significant antioxidant properties and are known to interact beneficially with the starch structure [55,56,57], Figure 5.

This native starch modification strategy is widely used to improve various products, such as biofilms [58], breads [59], and pasta [60,61]. According to Bhandari et al. [62], the incorporation of phytochemicals from herbs into pasta provided macromolecular-structural interactions of the starch with the constituents, altering its functional properties, cooking profile, and in vitro digestibility, but without structural modifications. Mu et al. [63] observed the potential of using polyphenols in low glycemic index starch-rich foods for the prevention of obesity and related metabolic diseases.

5. Bioaccessibility of Phytochemicals

The bioaccessibility of phytochemicals is significantly influenced by the food matrix and food processing, with their interactions with components such as water, proteins, lipids, and carbohydrates capable of either increasing or decreasing the availability of these bioactive compounds to the organism [64]. Current research in food science aims to develop healthier products by incorporating natural bioactive compounds, such as polyphenols and carotenoids, which promote well-being. According to Mishra et al. [65], cereal-based carbohydrate-rich products with bioactive phytochemicals represent an innovative approach to improving food quality. These studies show that the bioavailability of phytochemicals, when interacting with nutrients, food matrices, and vitamins, follows a complex physicochemical and biological progression, potentiating the therapeutic action of biomolecules and increasing their circulation in the organism. As an example, Huang et al. [66] observed that hawthorn flavonoids possess antioxidant capacity and inhibit starch hydrolysis, reducing its digestibility by glucosidase. Rocchetti et al. [67] studied the effect of adding Moringa oleifera L. leaf powder (MOLP) on phenolic bioaccessibility and the in vitro digestibility of durum wheat fresh pasta starch and observed that the inclusion of different levels of MOLP in the recipe increased the slowly digestible starch fractions and decreased the rapidly digestible starch fractions and the hydrolysis index of the cooked samples to the optimal point. These modifications are explored in studies aiming at the slow and controlled digestion of modified starches intended for various sectors.

6. Digestibility and Controlled Release Using Phytochemically Modified Starches

Digestibility and release can be controlled with the support of native or phytochemically modified starches. Zadeike et al. [68] analyzed the structural and functional characteristics of a starch-based gel product with an optimized composition of rice bran and lingonberry (Vaccinium vitis-idaea L.) dietary fiber, enriched with phytochemicals, finding that the resistant starch maintained its matrix stability after the immobilization of phytochemical molecules, thus ensuring sustained release. Mu et al. [63] found that the addition of phenolics from sea buckthorn (Hippophae rhamnoides L.) modulated starch digestibility through physicochemical modifications caused by starch-phenolic molecular interactions, increasing the bioavailability of these compounds.

Oladele et al. [4] studied the effect of modifying corn starch with phenolic extracts from grape pomace and sorghum bran under alkaline conditions, finding that starch modification with phenolics resulted in a starch with a lower hydrolysis rate and good antioxidant activity, demonstrating that these changes enhance the potential of starch to be used in the production of functional foods with nutraceutical properties. Gisbert et al. [69] studied the interactions between seaweed polyphenols (Ascophyllum nodosum) and native and gelatinized corn starches, finding interactions between polyphenols and starch, such as the molecular entrapment of polyphenols in the enriched starch gel structure and increased bioactivity.

Chumroenvidhayakul et al. [70,71] investigated the incorporation of pitaya (Hylocereus undatus) peel powder into various flours and, subsequently, into biscuit formulations. The authors observed a significant reduction in starch digestibility, including its hydrolysis and glycemic indices, along with improvements in the pasting properties of the flours and a decrease in toxic compounds formed during biscuit baking.

Camelo-Méndez et al. [72] stated that although the individual health benefits of slowly digestible carbohydrates, fibers, and phytochemicals are known, the interaction of these components in pasta products, especially gluten-free ones, is still underexplored. According to the researchers, understanding the synergistic or antagonistic effects of these biocompounds on the physical, chemical, sensory, and nutritional properties of the products, as well as their influence on digestibility and bioavailability, requires further investigation. Xu et al. [54] evaluated different methods of starch modification with phenolics and found that, in addition to reducing digestibility, many other starch properties were altered, such as starch structure, type and degree of crystallinity, gelatinization and pasting properties, swelling power, and solubility. According to the researchers, the degree and trend of these changes are determined by the modification method, starch types, and phenolic types.

It is crucial to highlight that a significant portion of this research is directed towards developing solutions to alleviate the suffering of individuals with diabetes, who often must restrict their intake of starchy foods due to their health conditions. Health, as is often noted, gains its full appreciation when it is lost. The characteristics acquired by starches enriched or modified with plant extracts can, moreover, benefit the pharmaceutical industry in developing controlled-release drugs, thus opening new frontiers for these biopolymers.

7. Biofilms and Bioactive Packaging

The biocompatibility and biodegradability of starch films, combined with the increasing demand for intelligent packaging, have driven the development of functional starch-based films [73]. The addition of bioactive compounds confers antimicrobial, antioxidant, and barrier properties to these films, making them a promising alternative for the food industry [50]. Edible biofilms are protective coatings made from biopolymers such as polysaccharides, proteins, and lipids, which are applied directly to food, offering a biodegradable alternative to conventional packaging [74]. Biofilms can also be used in fast-dissolving oral films, transdermal drug delivery, and soluble coatings for tablets [75,76].

Wahab et al. [77] developed a starch-based biofilm reinforced with cellulose microfibers isolated from banana rachis waste and found its applicability as a biodegradable and edible packaging film. Karmakar et al. [78] developed biodegradable films based on modified starch with nanostarch and tannic acid-coated nanostarch, which exhibit antimicrobial activity against Gram-positive and Gram-negative bacteria and almost complete biodegradation in soil within 10 days. Falah et al. [79] developed biofilms for food packaging formulated with starch-poly(lactic acid) and added lignin from pulp mills, and upon evaluating the antimicrobial activity, found activity against Escherichia coli, Salmonella typhi, Streptococcus aureus, and S. typhimurium. Phimnuan et al. [80] developed an anti-acne film from bacterial cellulose incorporated with dried pomegranate peel extract (Punica granatum) and observed its antibacterial efficacy, demonstrating its potential for acne treatment.

Mironescu et al. [81] highlighted the growing number of studies on the direct incorporation of plant extracts into starch-based packaging, with promising results regarding the antimicrobial, antioxidant, and mechanical properties of the films, as well as improvements in the packaged foods. According to the authors, the development of primary starch-based films and coatings containing bioactive compounds implies health benefits, emerging as a potential revolution in sustainable packaging.

It is crucial to note that a significant portion of agricultural production in many countries, particularly those in tropical regions like Brazil, India, and China (especially their southern regions), is lost before reaching consumers. Coincidentally, these nations are among the top researchers in phytochemically modified starches, very likely driven by the urgent demand for packaging solutions that effectively protect agricultural produce and extend its shelf life. This synergy between the need to mitigate losses and the advancement of research in green starches underscores the strategic role of these innovations for global food security and sustainability.

8. Herbal Excipients for Pharmaceutical and Cosmeceutical Applications

Pharmaceutical excipients are generally defined as inactive ingredients used in conjunction with therapeutically active compounds to formulate pharmaceutical substances. However, current studies demonstrate that these excipients increasingly influence the quality, efficacy, performance, and functionality of the drug [82]. Therefore, pharmaceutical excipients are no longer being considered inert substances, as studies have proven that excipients alter the rate at which drugs are released from formulations, influencing the efficiency of the system and the absorption of active pharmaceutical ingredients [82,83].

Starch is one of the main polysaccharides used as a pharmaceutical excipient, and research into the use of regional native starches should be encouraged [84]. As a result, there is a growing trend towards the use of naturally obtained excipients, known as “herbal excipients” [85]. Natural or herbal excipients have significant advantages over their synthetic counterparts, as they are non-toxic, low-cost, and freely available [86]. The performance of these excipients partly determines the quality of medicines, and they are obtained from various parts of plants, such as gums acquired by the plant, mucilage of natural origin (e.g., carrageenan, thaumatin, storax, agar, acacia gum, tragacanth), and polysaccharides like starch [87]. According to Ahmed et al. [88], these characteristics make these excipients ideal for herbal medicines, and through studies and modifications, they can be directed towards specific applications. These natural excipients can be easily altered to meet specific needs, becoming more potent to fulfill many requirements of the pharmaceutical vehicle and economical for transporting active pharmaceutical ingredients in the formulation [89].

According to Deshmukh et al. [90], the efficacy of natural cosmetics derived from herbs is often compromised by the inclusion of potent synthetic chemicals in their preparations, which can ultimately pose health risks and undermine the product’s inherent natural character. In this context, starches enriched with plant extracts present a valuable utility as excipients in cosmetic formulations, effectively delivering these bioactive constituents. While numerous natural excipients are generally considered safe, it remains crucial to assess their potential toxic effects, particularly when dealing with compounds of high concentration or significant structural complexity [91].

9. Slow and Controlled Release Fertilizers

Renewable biopolymers, such as starch, are being used as coatings for fertilizers, replacing petroleum-based polymers, and in hydrogels to improve water retention in the soil and optimize irrigation [92]. Another application that demands the use of starches enriched with plant nutrients, with potential for studies and applications of phytochemically modified starches, is that of slow and controlled release fertilizers [93]. These fertilizers release nutrients gradually, reducing losses and damage to roots, increasing the efficiency of fertilizer use, and allowing for less frequent applications [94].

Shang et al. [95] utilized functional, eco-friendly nanocarriers based on corn starch with controlled release of carvacrol (a phenolic monoterpenoid compound found in the essential oils of oregano, thyme, and bergamot) for persistent control of tomato gray mold, achieving success in the controlled release and foliar retention of this natural fungicide. Chamorro et al. [96] developed a highly efficient fertilizer using cassava starch and citric acid hydrogels for the slow release of ammonium and potassium. Zhou et al. [97] developed pH- and enzyme-responsive pesticide microcapsules using carboxylated porous corn starch loaded with avermectin within tannic acid–iron complexes as an encapsulating agent, improving insecticide efficacy and reducing toxicity to non-targets. According to the researchers, the results showed that the modified starch-based microcapsules constitute an environmentally friendly alternative.

Various starch sources have been explored in the agrochemical industry, suggesting that these biomaterials may have promising applications in the manufacture of high-efficiency fertilizers [98,99]. Therefore, there is a significant demand for alternative modification approaches, moving away from conventional chemical methods and strongly aligning with the principles of green chemistry, to address key drawbacks and substantially reduce environmental impacts.

10. Starch-Based 3D and 4D Printed Foods

According to Zhang et al. [100], three-dimensional (3D) printing is a technique used to construct complex geometric shapes for the creation of personalized foods, with the use of starch in the composition being notable due to its good rheological and gelling properties. The main focus of research has been on the utilization of fruits, vegetables, chocolate, dairy products, meat, and aquatic items as raw materials. Yang et al. [101] evaluated the 3D printing properties of potato starch gels with added lemon juice and found that the adhesiveness of the lemon juice gels improved differently as the starch content increased. Montoya et al. [102] developed a waxy starch gel incorporated with freeze-dried mango for use in 3D printed foods and found that the pectin from the mango acts as a gelling, stabilizing, and thickening agent in the gel. Zhao et al. [103] studied the effect of different types of starch (potato, wheat, corn, cassava, and mung bean) on the quality of 3D printed food products containing tomato extract, verifying that wheat starch obtained the best printing ability, appearance, and printing precision.

As for 4D printed foods, these are those that alter their physical characteristics, such as color, in response to external stimuli over time [104]. Huang et al. [105] developed rice starch-based gels with added anthocyanins (0.3%) extracted from purple sweet potato, intended for 3D printing, improving sensory acceptability and reducing starch digestion. Wang et al. [106] combined pH-sensitive pigments (anthocyanins) extracted from purple potato powder with an electrolysis technique using cooked peeled yam as a raw material for 3D food printing, demonstrating the potential of this enrichment due to its low cost, convenient control, and simple composition. Shanthamma et al. [104] developed turmeric powder incorporated into sago flour at various levels (0, 0.5, 1.5, 2.5% w/w) and used it as a 3D and 4D printing material supply. Ghazal et al. [107] utilized freeze-dried purple cabbage juice, gum arabic, and whey protein isolate composite microparticles as a smart material to achieve a rapid color change in 3D printed apple/potato starch gel in response to microwave heating stimulation. According to the authors, by changing the color from yellow to red, the consumer gains control over the baking temperature, preparation time, and greater visual appeal.

Figure 6 presents a schematic representation of 3D and 4D food printing using starch-based formulations enriched with plant extracts. In this context, 3D printing facilitates the fabrication of customized food structures, whereas 4D printing incorporates dynamic transformations—such as color changes—induced by external stimuli, including time, temperature, and pH.

Recent research in starch-based 3D and 4D printed foods appears to extend beyond fundamental nutritional and food safety aspects. There is a notable redirection of investments and research efforts towards enhancing the functionality, practicality, and aesthetics of these foods. This trend aims to add value to the final product, which, in turn, contributes to its market appreciation and consumer perception.

11. Self-Regulating Starch-Based Wound Dressings

Polysaccharide-based hemostatic dressings are widely used in the treatment of external and internal bleeding, including massive hemorrhage and in compressible or non-compressible locations [108]. Many commercial hemostatic products are based on natural polymers such as cellulose, starch, chitosan, hyaluronic acid, and alginate, exhibiting high hemostatic efficacy and biocompatibility [109]. Punyanitya et al. [110] developed a rice starch and paper-based adhesive bandage for wound dressings. Costa et al. [111] developed polymeric films containing pomegranate peel extract based on PVA/starch/PAA blends for use as a wound dressing and obtained non-hemolytic and antimicrobial activity against Staphylococcus epidermidis and Staphylococcus aureus. The researchers attributed the addition of the plant extract to the promotion of interactions between the polymer chains, which allowed the production of films without phase separation, and with continuity and integrity. Xu et al. [112] developed hydrogels with in vivo antibacterial action based on potato starch added with carvacrol (5-isopropyl-2-methylphenol), extracted from natural sources such as oregano and thyme, and gallic acid, intended for wound healing. Pagano et al. [113] developed a sustainable hydrogel based on corn starch loaded with saffron petal extract (Crocus sativus) and observed that in vitro studies on keratinocytes, the extract obtained by maceration (rich in gallic and chlorogenic acids) stimulates their growth in a safe concentration range (0.02–0.4 mg/mL), suggesting a potential application in skin diseases such as superficial wounds. Furthermore, the researchers observed antimicrobial activity against S. epidermidis and self-preservation capacity. Leon-Bejarano et al. [114] developed bioactive films based on potato starch with pecan or hazelnut shell extracts and observed that the films are slightly hemolytic. The bioactive films with 0.25% and 0.50% (w/v) of extracts showed antibacterial activity against S. aureus, S. epidermidis, and K. pneumoniae, potentially having application as wound dressings.

With constant technological advancements and the increasing integration of numerous synthetic materials into our daily lives, there appears to be a concomitant rise in consumer allergies and adverse reactions. In this context, the inclusion of biomaterial studies for the development of tissues and elements that will come into direct contact with the skin, especially when it is unprotected as in the case of a wound, is of utmost importance. When considering products intended for children and the elderly, the relevance of these studies extends to a vast field yet to be explored, offering safer and more biocompatible solutions for both the pharmaceutical and, as will be discussed, the textile industries.

12. Textile Industry and Fabrics Incorporating Bioactive Agents

Although synthetic antimicrobials are very effective against bacteria, these compounds are harmful to both human health and the environment. This has led to research into plant-based antimicrobial compounds for the textile industry [115]. These textiles are used in household materials, air filters, food packaging, sportswear, storage, ventilation, and water purification systems [116]. According to Ortega et al. [117], bioactive compounds derived from products or by-products such as roots, flowers, seeds, leaves, sprouts, and fruits can be used in fabrics due to their essential properties. El-Zawahry et al. [118] developed active textile packaging with cotton fabric coated with betalain extract encapsulated in gelatinized corn starch and gum arabic, obtained from red beet root. Rehan et al. [119] developed multifunctional cotton gauze fabrics using guava leaf powder extract in a starch core and calcium alginate outer membrane, noting antimicrobial, antioxidant, UV protection, and healing properties.

According to Danila [120], another market niche that utilizes natural polymers is that of aromatherapeutic textile materials, which employs essential oils to obtain functional textile materials with therapeutic and well-being effects. Akinropo et al. [121] evaluated the tensile and dye absorption properties of cotton fabrics sized with corn and sorghum starches, observing an increase in fabric tenacity and a blocking capacity in the fiber matrix for dye absorption and transport. Kovačević et al. [122] utilized acid-hydrolyzed modified corn starch as a substitute for synthetic sizing agents, noting that the synthesized corn starch improved the physical–mechanical properties of cotton yarns and abrasion resistance and reduced yarn surface hairiness. Admase et al. [123] added tannins as a tackifying agent and kaolin clay as a filler to different proportions of cassava starch, observing that the adhesive properties were enhanced in terms of thermomechanical aspects, moisture absorption resistance, bond strength, and stability, proving to be a viable alternative for the textile sector.

13. Starch-Based Green Electronics

Starch, as one of the most abundant natural polymers, has shown great potential in the development of environmentally friendly flexible electronics due to its low cost, good processability, and biodegradability [124]. The strong wettability of starch by polar solvents and the ability of hydrophilic groups to interact preferentially with the saline anion, which increases salt solubility and cationic transport properties, direct starch towards various applications, such as in battery electrolytes [125,126]. Lin et al. [127] researched starch-based membranes for the application of all-solid-state lithium-sulfur batteries and found that corn starch with LiTFSI exhibits excellent conductivity, with this starch electrolyte being stable up to 4.8 V, a stability higher than that of a commercial liquid system (4.2 V). According to Ahmed et al. [88], when starch is enriched with carbon, it acquires fully decomposable characteristics, making it an excellent biopolymer that can be used as a precursor to fabricate hierarchical porous activated carbon-derived electrodes, which can be employed for wearable, lightweight, and portable electronic devices.

Wu et al. [128] designed and constructed hydrogels from pure native sweet potato starch and obtained mechanical and electrical properties similar to those of tissue, with high sensitivity to deformation and signal-to-noise ratios and long-term reliability. According to the study, the starch hydrogels showed instantaneous and reversible self-adhesivity to a wide range of materials and potential applications in bioelectronics, including wearable biosensors and epidermal bioelectrodes.

Jeong et al. [129] conducted research with starches for the fabrication of flexible organic transistors using pentacene, dinaphtho [2,3-b:2′,3′-f]thieno [3,2-b]thiophene, and poly(dimethyl-triarylamine) via vacuum and solution processes. The researchers observed good performance in robustness tests using various chemical solvents, excellent stability to nonpolar solvents, good electrical performance, and ecological biodegradability.

Peregrino et al. [130] demonstrated the potential of starch (potato) as a central component in the construction of sensors based on graphene oxide (GO) and reduced graphene oxide, highlighting significant advantages over the use of conventional polyelectrolytes such as PDAC. The authors emphasized that starch is responsible for multiple roles in the device’s performance, such as the ability to form hydrogen bonds with GO, favoring efficient film assembly, in addition to being a more economical and sustainable alternative. It was observed that during the photoreduction of GO, starch acts as an additional source of electron density, accelerating the process more effectively and ecologically, without generating waste. Furthermore, its hydrophilic and hygroscopic properties increase the sensitivity of the sensors to humidity, while sensors with PDAC showed lower sensitivity due to their hydrophobic nature.

Liu et al. [131] developed a flexible, multimodal, and degradable sensor from a potato starch film using laser-induced porous carbon. The device demonstrated high sensitivity and versatility, detecting strain (gauge factor (GF) = 134.2, response time of 130 ms, and stability > 1000 times), temperature (25–90 °C), and pressure (0–250 kPa). According to the researchers, in addition to monitoring human movements and multiple stimuli, its ability to degrade in water highlights its potential as a “green” material for applications in smart and environmentally friendly devices.

Raeis-Hosseini and Lee [132] explored the use of potato starch in resistive random-access memory (ReRAM) devices, demonstrating its viability as a biocompatible material for biomedical applications. According to the research, the starch-based ReRAM exhibited flexible, transparent, and robust characteristics, while the combination of starch with chitosan enabled control over the resistive switching behavior. Devices with pure starch exhibited abrupt current changes, while the mixture with chitosan provided gradual changes, suitable for neuromorphic applications. According to the authors, the results highlight starch as a promising component for sustainable and high-performance non-volatile memories.

Sarkar et al. [133] introduced thermoplastic corn starch (TPS) as a positive triboelectric material in triboelectric nanogenerators (TENGs), highlighting its applicability in energy harvesting devices and self-powered sensors. The TPS-based TENG (b-TENG) demonstrated excellent performance, generating a peak voltage of approximately 560 V, a current density of 120 mA/m², and an instantaneous output power density of 17 W/m². The researchers were able to power more than 100 LEDs, LED strips, and LCD screens. The developed b-TENG functioned as a self-powered pedometer, speedometer, and gait sensor for physical activity analysis, showing biomedical potential.

The long-standing challenge of human organism rejection of exogenous agents remains a crucial frontier for scientific endeavor. With the unprecedented advancement of increasingly intrusive and technologically laden prostheses, the interfaces and connections employed demand impeccable consonance with the host body’s acceptance. In this landscape, natural polymers like starch emerge with vast potential to be explored in the quest for solutions to this intrinsic biocompatibility. Far from disregarding the notable and long-recognized acceptability of many established synthetic polymers, it is for a civilization that literally aspires to interstellar colonization and a deeper integration with technology that research in this realm of biomaterials becomes indispensable, meriting the utmost attention. The future of human–machine interaction and sustainable technological advancement rests, in part, on the capacity of green chemistry and electronics to unite in harmony with nature.

14. Recent Advances and Future Perspectives

Table 1. Examples of starch modification through the addition of phenols or phytochemicals, along with their associated outcomes and applicability.

Starch/Polyphenol Source	Observed Results	Potential Applications	Reference
Sweet potato flakes enriched with chia seeds.	Reduced harmful lipids and liver enzyme levels. Preserved heart tissue and reduced inflammatory markers. Showed significant nutritional and cardioprotective benefits.	Therapeutic foods.	[134]
Acerola (Malpighia emarginata DC) cassava starch.	Incorporation of polyphenols and increased radical scavenging activity.	Biodegradable edible films.	[135]
Japonica rice (cv. Koshihikari) with Morus alba L. leaf powder.	Reduction of glycemic index; decrease in starch particle size.	Functional beverage for reducing postprandial hyperglycemia.	[136]
Maize starch–steviol glycoside.	Improved the sensory quality, enhanced the release efficiency of starch hydrogel, and promoted the gelatinization and gelation of starch.	Development of sugar-free starchy foods.	[137]
Black gram husk and starch-soluble.	Increased the resistant starch content; reduction of estimated glucose index.	Functional ingredient with antioxidant activity.	[138]
Rice starch and Dragon Fruit Peels.	Low solubility, low water vapor permeability, and higher levels of total phenolic compounds and antioxidant activity.	Edible Starch-Based Films.	[139]
Eggplant peels, wheat flour.	Increased water absorption, reduced bread volume, and delayed the staling of baked pan bread.	Functional or enriched fiber foods.	[140]
High methoxyl pectin (HMP) and phosphated cassava starch (PCS), combined with Calendula officinalis extract (CoE).	Strong interfacial adhesion between HMP and PCS, prolonged disintegration time, higher percentage of elongation, and mucoadhesiveness.	Mucoadhesive oral applications.	[141]
Semolina pasta and grapefruit albedo.	Reduced cooking time; weaker matrix due to fiber increment.	Functional foods.	[142]
Rice starch by Matcha extract (powder of the leaf of Camellia sinensis).	Solubility and swelling power of starch were increased; reduced the Glycemic Index and resistant starch was increased.	Functional foods.	[143]
Wheat flour, potato starch, and rice flour, purple cabbage, black grapes, holy basil, pumpkin, carrot, and beetroot.	Best regarding appearance, color, texture, taste, flavor, and overall acceptability.	Eco-friendly edible wrappers.	[144]
Plantain pulp starch and chitosan, Plectranthus barbatus and Plectranthus caninus extracts.	Increased opacity, density, and moisture content alongside decreased swelling indices, and gram-positive and gram-negative bacteria inhibition.	Sustainable food packaging.	[145]
Cassava starch and Vismia guianensis.	Improved flexibility and stability of the bioplastic, with significant improvements in mechanical and thermal properties.	Potential use in biomedical applications.	[146]
Corn starch, Selenium nanoparticles, litchi fruit.	Reduced dehydration, inhibited microbe growth, and biodegradability.	Multipurpose active food packaging.	[147]

presents examples of starch modification through the addition of phenols or phytochemicals, along with their associated outcomes and applicability. Publications from 2024 and 2025 on phytochemically modified or enriched starches primarily highlight two research domains: Food and Nutrition, and Sustainable Packaging. In Food and Nutrition, emphasis is on glycemic control via starch digestibility modulation and integrating antioxidant/cardioprotective properties to enhance product quality and consumer appeal. Sustainable packaging focuses on developing biodegradable, edible films with antimicrobial and antioxidant properties to extend shelf life and reduce waste, aligning with circular economy principles. A lesser but emerging trend is the application of these starches in biomedical and pharmaceutical contexts, including mucoadhesive uses.

Despite the expanding body of research, several critical gaps and challenges persist across these areas. Key challenges include the development of packaging materials that are simultaneously robust, flexible, and fully biodegradable. Additionally, there is a pressing need for economically and industrially viable, large-scale, reproducible biofilms that can attract significant industrial interest. Another crucial area requiring further investigation involves the effective partial or total replacement of fats using starches and their derivatives.

15. Conclusions

This study highlights a growing demand, particularly in the last decade, for sustainable alternatives in the exploration and application of native, modified, and biocompound-enriched starches. Although chemical modifications offer practicality and economy, there is a growing consensus on the need for less impactful and safer alternatives. In this context, the use of phytochemicals in conjunction with starches has been the subject of increasing research.

In the pharmaceutical and nutritional fields, the search for resistant starches with controllable properties, especially as carriers of bioactive compounds, has been the focus of recent research. Similarly, significant advances can be observed in areas such as slow and controlled release fertilizers, as well as self-regulating wound dressings based on enriched starches. In the textile industry, starch continues to be studied as a sizing agent, color fixative, and incorporator of bioactive compounds, as well as a promoter of texture and other functional properties. These characteristics have also been studied and exploited in the development of biodegradable packaging and biofilms.

Whether as an additive, ingredient, adjuvant, or plant-based filler, the multiple properties of starch still offer vast potential to be explored. New segments, such as bioelectronics and 3D and 4D food printing, are adopting these characteristics to develop technological innovations. Thus, the versatility of starch, especially when combined with plant extracts or phytochemicals, reaffirms its strategic role in the development of sustainable and innovative solutions for a wide range of industrial applications.