Starch-based films: Major factors affecting their properties

Development and characterization of an aromatic and antioxidant active film based on myofibrillar protein from fish by-products and passion fruit essential oil

This study aimed to develop and characterize an aromatic and antioxidant film based on myofibrillar proteins from the cutting by-product of Scomberomorus brasiliensis filleting on the band saw machine and yellow passion fruit essential oil. Four formulations were produced, varying the concentrations of essential oil of the yellow passion fruit (YPF): C (control, without YPF), O4 (with 0.4 % YPF), O8 (with 0.8 % YPF), and O12 (with 1.2 % YPF). The films were evaluated for mechanical, optical, barrier, structural, thermogravimetric, and degradability properties. The volatile compound profile and antioxidant activity of the films and the oil were also evaluated. The addition of the YPF favored the formation of a structure with less thickness and proportionally reduced the films' water solubility (18.72 to 14.50 %) and water vapor permeability (23.86 × 10-12 to 2.74 × 10-12 g/m s Pa). The films' degradation time in soil was not affected by the incorporation of YPF, with all samples showing 100 % degradation within 15 days. The YPF also efficiently reduced fish odor and incorporated passion fruit aromas in the films. The antioxidant activity of the films increased with the addition of YPF, presenting high values for total phenolics (1.02 to 4.89 mg GAE/g), ABTS (260.21 to 505.52 mMol ET/g), and DPPH (31.83 to 326.21 mMol ET/g). The O12 treatment proved to be the most promising active biodegradable material for making antioxidant packaging for foods sensitive to oxidative reactions due to its stable structure, low solubility, water permeability, desirable aroma, and high antioxidant activity.

Production of polysaccharide and protein edible films: Challenges and strategies to scale-up

Polymeric films are among the main packaging materials used by food industry, and they can be produced using petrochemical-based polymers and biopolymers. Although the use of petrochemical-based polymers for food packaging is associated with a harmful impact on the environment, and human health through direct contact with food, the food industry cannot avoid their use due to the lack of fully viable alternatives. Therefore, there is an imperative need for potential food packaging alternatives made from natural, bio-based polymers that should be safe and biodegradable. In this group, edible polysaccharides and proteins present several advantages, making them green and safe alternatives. Therefore, several pilot and semi-commercial attempts have been made to commercialize the production of edible packaging materials. However, their industrial-scale production still presents big challenges. These challenges are related to the properties of edible biopolymers, such as low elasticity and high hygroscopicity, and, others are associated with the commercial-scale manufacturing technologies, which causes a slower implementation of edible films at the industrial level. This study aims to discuss edible films' main properties and limitations and propose possibilities for their industrial-scale production, focusing on maintaining their natural and ecofriendly food packaging with evolved functionalities.

Development and characterization of starch/polyvinyl alcohol active films with slow-release property by utilizing Mucorracemosus Fresenius mycelium to load with clove essential oil

The controlled release active packaging film represents a novel technology that always can effectively slow down the release of active agents, extending their efficacy. Mucorracemosus Fresenius (MF) mycelium was prepared and used as an adsorption carrier to load clove essential oil (CEO). The CEO/MF complexes were incorporated into the starch/polyvinyl alcohol (Starch/PVA) matrix to develop active films. The effects of MF content on the films' properties were investigated. MF exhibited the internal hollow structure with diaphragm inside and showed antioxidant activity. The adsorption rate of MF on CEO was 238.09 %. As MF increased, the tensile strength, water contact angle and gas barrier properties (water vapor and oxygen) of the films containing CEO enhanced. The release rate of CEO from the films into food simulant (10 % ethanol) slowed down significantly with increasing of MF. Compared to the film without MF, the film with highest MF delayed 33 h to reach equilibrium. The films with different content of MF showed different antioxidant and antibacterial activities, and different preservation effects on shrimp. It showed a great prospect to develop controlled release active films by utilizing MF mycelium as an adsorption material, which enriched the technical solutions for developing controlled release active packaging films.

Recyclable PVA/starch/Ti3C2Tx MXene nanocomposite films with superior mechanical and barrier properties

The fabrication of eco-friendly and high-performance composite materials has gained significant attention for multifunctional applications. Polyvinyl alcohol (PVA)/starch composite films containing varying amounts of Ti3C2Tx MXene (2.5-10 wt%) were produced using a simple casting method. The impact of MXene nanoplatelets on the films' chemical structure and physical properties were thoroughly analysed. It was revealed that MXene formed hydrogen bonding with the polymer matrix and tended to align in the plane of the films. The mechanical properties of the PVA/starch blend were significantly improved with increasing MXene loading. With 10 wt% MXene, the Young's modulus (YM) and tensile strength (TS) increased by 669 % (from 255.7 to 1965.3 MPa) and 292 % (from 9.2 to 36.1 MPa), respectively. Additionally, the presence of MXene greatly improved the films' water and oxygen barrier properties, reducing water vapor permeability (WVP) by 91 % and oxygen permeability (OP) by 79 %. These improvements are attributed to the homogeneous dispersion of MXene within the blend and the interfacial interactions between the components. Furthermore, the PVA/starch/MXene composite films exhibited excellent recyclability, maintaining their mechanical and barrier properties even after recycling, demonstrating their potential for repeated use without performance loss. Overall, the developed composite films present a promising sustainable solution for applications in materials requiring advanced mechanical and barrier performance.

Effects of different ratios of glycerol to erythritol on the structure and properties of starch straws during long term storage

To explore starch straws with low water absorption rate (WAR) and not prone to brittleness during long term storage. Glycerol and erythritol were used as composite plasticizers to explore their effects on the structure of starch straws. The results showed that G:E (60:40) had the lowest bending force (Fb = 12.58 N) and relative crystallinity (RC = 10.05 %). G:E (40:60) had the lowest water absorption rate. With the increase of erythritol contents, the proportion of starch straws short chains (A + B1) increased. Starch straws are easier to be broken during long term storage as the percentages of erythritol increased from 80 to100. However, G:E (40:60) and G:E (60:40) not only had higher flexibility (Eb = 6.12 N/cm and 7.47 N/cm) but greater hardness (Fb = 39.37 N and 45.42 N). Therefore, the addition of glycerol can inhibit the precipitation of erythritol and has an ideal plasticizing effect than single plasticizer.

Tapioca starch/konjac gum-based composite film incorporated with nanoliposomes encapsulated grape seed oil: Structure, functionality, controlled release and its preservation role for chilled mutton

In this study, grape seed oil nanoliposomes (GSO-NLs) were constructed and doped into tapioca starch/konjac gum composite films (TK-GSO-NLs) to evaluate the preservation of chilled mutton. The results showed that the GSO-NLs have a good spherical or rounded state and good stability. The doping of GSO-NLs resulted in a smooth, flat, and dense structure on the surface and cross-section of the TK films. The TK-GSO-NLs showed the best compatibility among the components, with excellent mechanical and barrier properties. FTIR and XRD confirmed the presence of ionic bonds between the components, further improving the copolymer crystal structure. Notably, the packaging material provided ideal antioxidant and bacteriostatic stability as well as delayed GSO release. This packaging could effectively maintain the quality of chilled mutton and prolong the shelf-life to 15 days. The study provides ideas for the design of green and active food packaging and for extending the shelf life of meat.

Correlation analysis of starch molecular structure and film properties via rearrangements of glycosidic linkages by 1,4-α-glucan branching enzyme

The functional characteristics of starch films are significantly influenced by the amylose content and the distribution of the amylopectin chain length. This work used 1,4-α-glucan branching enzyme to molecularly reconstruct corn, pea, and cassava starch in order to examine the association. Films made of both natural and enzyme-modified starch were produced using the casting method. The study investigated the variations in starch films properties and explored the relationship between starch molecular structure and film qualities by correlation analysis. The results showed a significant positive connection (r = 0.954) between the tensile strength and amylose content, as well as a positive correlation (r = 0.939) between the A chains and the elongation at break. The average chain length (r = 0.932) and amylose content (r = 0.902) showed a positive correlation with the degradation temperature, whereas the amylose content (r = -0.946) showed an adverse correlation with the transparency. The B3 chain (r = 0.851) and the average chain length (r = 0.839) both exhibited a positive connection with its contact angle. As a result, our study thoroughly assesses how starch structure affects the characteristics of starch films and offers a fundamental modification pathway for the development of new application areas.

Valorization of raw papaya (Carica papaya) and citrus peels for development of antimicrobial and biodegradable edible film

Most of the food packaging materials used in the market are petroleum-based plastics; such materials are neither biodegradable nor environmentally friendly and require years to decompose. To overcome these problems, biodegradable and edible materials are encouraged to be used because such materials degrade quickly due to the actions of bacteria, fungi, and other environmental effects. The present study examined that starch can be effectively used as raw material to develop biodegradable, edible films. In this regard, Raw papaya and Citrus Peel were chosen to make biodegradable plastic film blended with corn starch. Raw papaya powder was combined with citrus peel powder for the development of film in treatments of T1, T2, T3, T4 and T5. RPP and CPP blend with Corn starch (CS) to maximize the film-forming properties and characteristics. The films were subjected to various parameter analysis like thickness, optical properties and barrier properties. As per the results, T3 was an optimized film, as it had minimum thickness (0.26 ± 0.01), high tensile strength (5.79 ± 0.12), elongation at break of 11.92 ± 0.03, High transparency (1.42 ± 0.06), and high degradation temperature. From the results, it is inferred that the prepared films are ideally suitable for food packaging and their production on a larger scale can considerably cut down the plastic wastage.

Intelligent color changing packaging film based on esterified starch and black rice anthocyanins

Intelligent packaging film has received more and more attention because it can help consumers obtain more intuitive information about the packaging, provide better preservation and advanced convenience. In this study, black rice anthocyanin (BRA) was added into composite film formed by starch (S) and esterified starch (ES). As the BRA content increased, the thickness and the total color difference of the S/ES-BRA film increased. The opacity of S/ES-BRA film decreased relative to that of the film without BRA, but increased with the increase of anthocyanin. Compared with S/ES film, the elongation at break of S/ES-BRA0.5 film increased from 33.1 % to 45.4 %, and the tensile strength decreased from 7.3 to 5.8 MPa. S/ES-BRA film had response to different pH values and underwent color changes in different buffer solutions. Intelligent color changing packaging film will used to monitor food quality, water quality and soil properties.

Production of Starch-Based Flexible Food Packaging in Developing Countries: Analysis of the Processes, Challenges, and Requirements

Biodegradable packaging offers an affordable and sustainable solution to global pollution, particularly in developing countries with limited recycling infrastructure. Starch is well suited to develop biodegradable packages for foods due to its wide availability and simple, low-tech production process. Although the development of starch-based packaging is well documented, most studies focus on the laboratory stages of formulation and plasticization, leaving gaps in understanding key phases such as raw material conditioning, industrial-scale molding, post-production processes, and storage. This work evaluates the value chain of starch-based packaging in developing countries. It addresses the challenges, equipment, and process conditions at each stage, highlighting the critical role of moisture resistance in the final product's functionality. A particular focus is placed on replacing single-use plastic packaging, which dominates food industries in regions with agricultural economies and rich biodiversity. A comprehensive analysis of starch-based packaging production, with a detailed understanding of each stage and the overall process, should contribute to the development of more sustainable and scalable solutions, particularly for the replacement of single-use packages, helping to protect vulnerable biodiverse regions from the growing impact of plastic waste.

The effect of the modified starch with side chain on the morphology of copper particles and the antibacterial properties of starch/copper composite material

In this paper, corn starch was modified by acetylation, esterification and amination, and the effects of different modifications on the structure and physicochemical properties of starch were investigated. And starch/copper composite materials were prepared by adding copper salts to the different modified starch, and the influence of modified starch and their additive amount on the morphology of copper and the antimicrobial properties were discussed. The results showed that: the contact angle of the modified starch was about 50° and exhibited hydrophilic-hydrophobic transition; the esterified starch had the smallest heat weight loss; the different modifications caused damage to the structure of the starch, which changed from the original smooth surface to a rough and wrinkled surface; hexahedral morphology copper particles were obtained by replacing them with the modified starch; the antimicrobial effect of the prepared starch/copper composite materials were related to the modification mode of starch, in which aminated starch show the best antimicrobial effect. This study provides a theoretical basis for the selection of starch type in the preparation of starch/copper composite materials in the future, which can also be used as antimicrobial components in other applications.

Physical and thermal improvement of bioplastics based on potato starch/agar composite functionalized with biogenic ZnO nanoparticles

This study investigated potato starch/agar-based bioplastics' structure, properties, and biodegradability by adding ZnO nanoparticles (NPs) biogenically synthesized using Coriandrum sativum extract. ZnO NPs presented crystalline structure, good optical properties, and a size of 6.75 ± 1.4 nm, which were added at various concentrations (419.66-104.23 ppm) in bioplastics and their presence was confirmed via EDS elemental analysis and X-ray fluorescence. The highest NPs concentration contributed to a smoother surface, while FTIR and Raman analyses suggested interactions between the NPs and functional groups of the biopolymeric matrix. ZnO NPs addition slightly reduced bioplastic transparency but significantly improved UV-A and UV-B blocking capacities. It also increased hydrophobicity, evidenced by a 22 % reduction in water absorption and a 55 % increase in contact angle. Thermogravimetric analysis (TGA) indicated that NPs raised the bioplastic's thermal stability. Mechanical property tests showed that ZnO NPs concentrations had negligible or negative effects probably due to the heterogeneous distribution of NPs, or the non-isotropic characteristic of the bioplastic. Finally, biodegradability assays in seawater and soil revealed over 43.5 % and 66 % degradation after 15 and 28 days, respectively. Therefore, biosynthesized ZnO NPs mainly enhanced the bioplastic's UV-blocking capacity, hydrophobicity, and thermal properties, offering an eco-friendly option for future studies/applications.

Strength, pliability, and hydrophobicity of mung bean starch straws: Orientation change caused by annealing time

To achieve starch straws with high strength and large toughness, the effects of annealing time on structural and functional performances of mung bean starch straws were studied. The results revealed that with increasing annealing time from 0to 60 min, the ratios of 1047 cm-1/1022 cm-1 in Fourier transform infrared spectroscopy decreased from 1.37 to 1.20, and the relative crystallinities decreased from 12.09% to 11.01%. The relative crystallinity increased to 13.28% when annealing time increased to 120 min. The maximum bending force increased from 10.93 to 104.24 N, and modulus of elasticity enhanced from 0.93 to 62.68 N/mm when annealing time increased from 0 to 120 min. Starch straws annealed for 120 min had the lowest water absorption (94.61%), while starch straws annealed for 60 min had the highest water absorption (127.38%). This outcome not only lay a theoretical foundation for preparing biodegradable starch straws with excellent performance, but also apply for beverages, food container, food packaging films, and so on, strongly promoting starch industrial transformation and development.

Substituting corn starch with wolf's fruit and butterfly lily starches in thermopressed films: Physicochemical, mechanical, and biodegradation properties

The industrial use of corn starch competes with food supplies, encouraging the investigation of native starches as an alternative for its partial replacement. This study aimed to analyze the effects of replacing corn starch (CS) with wolf's fruit (WFS) and butterfly lily (BLS) starches on the physicochemical, mechanical, and biodegradation properties of starch-based films. Plasticized (with glycerin and citric acid) and unplasticized films were prepared with a microwave (10 s) and by thermopressing (1.5 t/120 °C/2 min) and were analyzed for amylose, scanning electron microscopy, X-ray diffraction, and paste properties. Furthermore, the biodegradability of films was tested in two soils over 42 days. Our results show that BLS is not a suitable raw material to replace corn starch. WFS with 27.5 % apparent amylose content and granule size of 12.5 μm produced films with thickness, permeability, tensile strength, and elongation of ~110 μm, ~4.8 g (m.s.Pa)-1, ~2.5 MPa, and ~2.9 %, respectively, similar to CS. The biodegradability of WFS film showed greater resistance (≤61.4 %), increasing with the addition of plasticizers (89-93 % for WFS302) or partial replacement of CS (73-91 % for CSWFS303). These findings indicate that WFS can partially or fully replace CS in thermopressed films.

Dual cross-linked network of the active starch film by incorporating palmitic acid and geraniol: A comprehensive evaluation of the hydrophobic mechanism and antimicrobial activity

In this study, (3-Aminopropyl) triethoxysilane (APTES) was employed as a bridging agent to enhance the compatibility between the hydrophilic starch/pectin film and the hydrophobic palmitic acid (PA) coating through hydrogen bonding and chemical reactions. To address the insufficient antibacterial activity of starch films, geraniol was also incorporated. The intermolecular interactions among APTES, PA, and starch were confirmed using x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and hydrogen nuclear magnetic resonance spectroscopy (1H NMR). Notably, the inclusion of APTES and PA significantly increased the film's hydrophobicity, resulting in a water contact angle (WCA) of 95.12°, a water vapor permeability (WVP) of 2.08 × 10-10 g/(mm·s·Pa), and an oxygen permeability (OP) of 2.61 × 10-9 g·mm·mm-2·s-1. Molecular dynamics (MD) simulations revealed strong non-covalent interactions and exceptional compatibility between starch and PA. Furthermore, the integration of pectin and geraniol improved the mechanical strength and antimicrobial properties of the modified films compared to unmodified starch films. These environmentally friendly and biodegradable starch-based films present a promising option for sustainable packaging materials in food preservation.

Rheological and Textural Investigation to Design Film for Packaging from Potato Peel Waste

The recovery of potato waste for circular-economy purposes is a growing area of industrial research. This waste, rich in nutrients and potential for reuse, can be a valuable source of starch for packaging applications. Rheology plays a crucial role in characterizing film-forming solutions before casting. In this work, packaging film was prepared from potato waste using rheological information to formulate the film-forming solution. To this aim, rheological measurements were carried out on starch/glycerol-only samples, and the data obtained were used to optimize the formulation from the waste. The polyphenol content of the peels was analyzed, and the resulting films were comprehensively characterized. This included assessments of color, extensibility, Fourier-transform infrared (FT-IR) spectroscopy, surface microscopy, and contact angle. Polyphenol-loaded films, suitable for packaging applications, were developed from potato waste. These films exhibited distinct properties compared to those made with pure starch, including an improved wettability of about 75° for the best sample and a high elastic modulus of about 36 MPa, which reduces the deformability but enhances the resistance against the stress. Through rheological studies, we were able to design films from potato peel waste. These films demonstrated promising mechanical performance.

Exploring urea as a prospective auxiliary for starch functionalization: A concise review on modified starch properties and the sustainable packaging films

Urea is also known as carbamide, an inexpensive and eco-friendly additive for starch functionalization. This article reviews the potential role of urea in starch modification, with the prominence of the mechanism of urea action, alterations in the starch structure and functional properties. In addition, current literature conveys the prospective effect of urea in fabricating starch films for food packaging, and the relevant areas that need to be covered in the forthcoming research are specified at the end of the article section. Urea can modify the diverse physico-chemical and functional properties of starch. Starch-based films exhibit pronounced effects on their mechanical and barrier properties upon the incorporation of urea, although this effect strongly depends on the urea content and degree of substitution (DS). Overall, urea holds great potential for use in the starch and bioplastic film industries, as it produces biocompatible derivatives with desirable performance.

Maintenance of postharvest quality of 'Palmer' mango coated with biodegradable coatings based on cassava starch and emulsion of lemongrass essential oil

This study aimed to evaluate the effect of applying oxidized cassava starch-based edible coatings with addition of lemongrass essential oil emulsion on 'Palmer' mangoes stored under refrigeration. A completely randomized design was used, arranged in a 5 × 3 factorial scheme, with five types of coatings and three evaluation times. The evaluated postharvest quality parameters consisted of weight loss, pulp and peel firmness, biochemical transformations related to pigments, and pulp and peel coloration of mango. The application of edible coatings with a 0.9 % EO concentration resulted in delayed fruit ripening, evidenced mainly by a 7.25 % reduction in weight loss, a 29.23 % increase in soluble solids content, and a 24.15 % decrease in total chlorophyll, when compared to uncoated fruits, which showed 19.8 %, 48.66 %, and 82.00 %, respectively, over the storage period. This effect was also evident in the angle Hue (°h) measurement, with uncoated fruits showing a decrease of 32.2 %. The antimicrobial effect and absence of anthracnose symptoms were observed in the fruits in which the coating with 0.9 % EO was applied. Therefore, biodegradable coating with the addition of 0.9 % emulsion EO, can be used as postharvest treatments for maintenance quality of 'Palmer' mangoes during refrigerated storage.

Photo-modified and photo-degradable starch/Fe3O4/TiO2 nanocomposite: exploring the feasibility of reducing workforce by magnetic recycling

Plastics are known for their durability and long decomposition time in the environment, which make plastic recycling an effective approach to mitigate plastic waste risks. However, the global plastic recycling rate is less than 10% mainly due to the labor-intensive and time-consuming nature of the manual recycling process, which poses high health risks and costs. Therefore, the development of a fast, effective, and operational process in current recycling plants is crucial to address the environmental concerns associated with plastics. In the current study, the feasibility of starch/Fe3O4/TiO2 bio-nanocomposite (SFT) as photo-modifiable and photo-degradable was investigated to reduce the workforce in recycling packaging material. The SFT was modified by different UV-C exposure times, which significantly altered its functional properties. The UV-C exposure increased the hydrophobicity of the SFT films and led to a homogenous distribution of Fe3O4/TiO2 nanoparticles (FT). It also increased tensile strength (TS) and decreased elongation at break (EB) of the films. It seems that producing shorter polymer chains, creating new linkages among the polymeric chains, and the homogenous distribution of FT in the matrix of biopolymer by UV-C are the main reasons for these changes. Moreover, the photo-degradation of SFT specimens increased significantly with longer UV-C exposure times. The utilization of magnetic properties in bio-based nanocomposites holds promising potential for streamlining labor-intensive processes in waste recycling plants. However, the inappropriate visual properties of SFT remain a significant obstacle that requires further attention to enable its commercial viability.

Synergistic effect of Hylocereus polyrhizus (dragon fruit) peel on physicomechanical, thermal, and biodegradation properties of thermoplastic sago starch/agar composites

The potential of Hylocereus polyrhizus peel (HPP) as a new eco-friendly reinforcement for thermoplastic sago starch/agar composite (TPSS/agar) was investigated. The integration of HPP into TPSS/agar composite aimed to enhance its mechanical and thermal characteristics. The study employed Fourier transform-infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), and Differential Scanning Calorimetry (DSC), as well as mechanical, physical properties and soil burial testing to analyse the composites. The results showed a favourable miscibility between the matrix and filler, while at higher concentrations of HPP, the starch granules became more visible. The tensile and impact properties of the composites improved significantly after incorporating HPP at 20 wt%, with values of 12.73 MPa and 1.87 kJ/m2, respectively. The glass transition temperature (Tg) and initial decomposition temperature (Ton) decreased with the addition of HPP. The density of the composites reduced from 1.51 ± 0.01 to 1.26 ± 0.01 g/cm3 as the HPP amount increased. The environmental properties indicated that the composites can be composted, with weight loss accelerating from 35 to 60 % and 61 to 91 % by the addition of HPP in 2- and 4-weeks' time, respectively. The study demonstrates the potential of TPSS/agar/HPP composites as eco-friendly materials for various applications.

Improving physicomechanical properties of arrowroot starch films incorporated with kappa-carrageenan: Sweet cherry coating application

Arrowroot starch (AS)-based films potential is influenced by its low-cost processing and high transparency packaging material but low tensile strength; hence, AS was blended with kappa-carrageenan (KC) to improve mechanical properties of AS-based films and enhance its potential use in food packaging or coating applications. AS-KC-based films were characterized based on structural, physicomechanical, thermal, pasting properties, and coating application in sweet cherry. The films demonstrated high tensile strength from 3.2 to 29.4 MPa and low elongation properties from 160.3 % to 1.9 %. Moreover, AS/KC films exhibited peak viscosities of 18.7 to 34.8 RVU, and thermal analysis depicted lower weight losses (59-45 %) compared to AS-based films (62 %). In addition, sweet cherry samples coated with AS/KC films and stored at 20 °C for 15 days depicted lower weight losses (26.6 %) compared to non-coated samples (>41 %), which indicated the potential use of the film's coating application in extending the shelf life and quality of fresh fruits.

Applications and characterization of anti-browning enzymatically modified potato starch (EPS) film associated with chitosan (CTS)/L-Cys/citric acid (CA) on fresh-cut potato slices

This study explores the influence of incorporating L-cysteine (L-Cys), chitosan (CTS), and citric acid (CA) on the enzymatic modification of potato starch (EPS) films to enhance anti-browning properties. Four types of EPS composite films were evaluated for preserving fresh-cut potato slices at low temperatures to inhibit browning. Their thermal, physiochemical, mechanical, and digestibility properties were assessed. Results indicate that the addition of CTS, CA, and L-Cys improved the anti-browning activity of the EPS films by increasing film thickness and reducing water vapor permeability (WVP), oxygen transmission rate (OTR), ultraviolet (UV) transmittance, and tensile strength (TS). Furthermore, these additives improved the film's microstructure, resulting in reinforced intermolecular interactions, increased elongation at break, heightened crystallinity, enhanced thermal stability, and favorable gastrointestinal digestibility. Overall, EPS/CTS/L-Cys/CA composite films show promise as edible packaging materials with effective anti-browning properties.

Starch-based films affected by the addition of collagen from Prochilodus magdalenae residues and HPMC: Application in Andean blackberry (Rubus glaucus Benth) coatings

Starch-based films offer the advantages of biodegradability, edibility, barrier properties, flexibility, and adaptability. This study compared the physicochemical properties of starch-based films by adding raw fish collagen and hydroxypropylmethylcellulose (HPMC). The tensile properties were evaluated, and the interaction with water was analyzed. Barrier properties, such as water vapor and oxygen permeability, were examined, and optical properties, such as gloss and good internal transmittance, were evaluated. The films were evaluated as coatings on Andean blackberries (Rubus glaucus Benth) for 2 weeks at 85% RH and 25°C. The results showed that the inclusion of collagen caused a reduction in the tensile strength and elastic modulus of the films. Also, the formulation with the highest collagen concentration (F7) exhibited the lowest weight loss and water vapor permeability, also it had the highest collagen concentration and showed the highest reduction in Xw and WAC, with values of 0.048 and 0.65 g water/g dry film, respectively. According to analyzing the optical properties, F1 presented the highest bright-ness and transmittance values, with 18GU and 82 nm values, respectively. In general, the films and coatings are alternatives to traditional packaging materials to prolong the shelf life of these fruits.

Effect of ultrasound/CaCl2 co-treatment on the microstructure, gelatinization, and film-forming properties of high amylose corn starch

The effect of ultrasound/CaCl2 co-treatment on aggregation structure, thermal stability, rheological, and film properties of high amylose corn starch (HACS) was investigated. The scanning electron microscopy (SEM) images revealed the number of starch fragments and malformed starch granules increased after co-treatment. The differential scanning calorimetry (DSC) results showed the co-treated HACS got a lower gelatinization temperature (92.65 ± 0.495 °C) and enthalpy values (ΔH, 4.14 ± 0.192 J/g). The optical microscope images indicated that lesser Maltase crosses were observed in co-treated HACS. The results of X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) indicated ultrasound influenced the compactness of amorphous zone and CaCl2 damaged the crystalline region of HACS granules. Additionally, the rheology properties of HACS dispersion demonstrated the apparent viscosity of co-treated dispersion increased as the ultrasound time prolonged. The mechanical strength and structural compactness of HACS films were improved after ultrasound treatment. The mechanism of ultrasound/CaCl2 co-treatment improved the gelatinization and film-forming ability of HACS was that (i) ultrasound wave loosened the HACS granules shell, promoted the treatment of CaCl2 on HACS granules, and (ii) ultrasound wave improved the uniform distribution of HACS dispersion, increased the interaction between CaCl2 and starch chains during the process of film-forming.

Cassava bagasse starch and oregano essential oil as a potential active food packaging material: A physicochemical, thermal, mechanical, antioxidant, and antimicrobial study

This research evaluates the use of cassava bagasse starch and oregano essential oil (OEO) in an active film. For comparison, films of cassava starch (CS) and cassava bagasse starch (BS) were prepared with OEO at 1, 2, and 3 %. Physical, thermal, mechanical, antioxidant, and antimicrobial properties were determined. BS films presented higher thickness, WVP, ΔE, modulus of elasticity, and maximum stress, but lower strain at break compared to CS films. Adding OEO into the films increased their thickness, moisture, solubility, WVP and strain at break. However, maximum stress, modulus of elasticity, and T dmax decreased. The CS films added with 3 % of OEO showed higher WVP (6.32 × 10-14 kg m/m2.s.Pa), intermediate solubility of 39 % and low maximum stress (0.19 MPa) while the BS film with 3 % of OEO presented 5.73 × 10-14 kg m/m2.s.Pa, 30 % and 0.39 MPa, respectively. The increase from 1 % to 3 % of OEO increased the total phenolic compound content and antioxidant activity of the films by 1.3-fold and 3.7-fold, respectively. The incorporation of 3 % OEO in the films inhibited the growth of S. aureus and E. coli. Therefore, BS and OEO films offer a promising solution as biodegradable active food packaging, providing a more sustainable alternative to traditional non-biodegradable plastic packaging.

Impact of Novel Foods on the Human Gut Microbiome: Current Status

The microbiome is a complex ecosystem of microorganisms that inhabit a specific environment. It plays a significant role in human health, from food digestion to immune system strengthening. The "Novel Foods" refer to foods or ingredients that have not been consumed by humans in the European Union before 1997. Currently, there is growing interest in understanding how "Novel Foods" affect the microbiome and human health. The aim of this review was to assess the effects of "Novel Foods" on the human gut microbiome. Research was conducted using scientific databases, focusing on the literature published since 2000, with an emphasis on the past decade. In general, the benefits derived from this type of diet are due to the interaction between polyphenols, oligosaccharides, prebiotics, probiotics, fibre content, and the gut microbiome, which selectively promotes specific microbial species and increases microbial diversity. More research is being conducted on the consumption of novel foods to demonstrate how they affect the microbiome and, thus, human health. Consumption of novel foods with health-promoting properties should be further explored to maintain the diversity and functionality of the gut microbiome as a potential tool to prevent the onset and progression of chronic diseases.

Enhancing mechanical and water barrier properties of starch film using chia mucilage

Biodegradable packaging materials are increasingly being investigated due to rising concerns about food safety and environmental conservation. This study examines the incorporation of chia mucilage (CM) into starch-based films using the casting method, aiming to understand its effects on the structure and functionality of the films. CM, an anionic heteropolysaccharide, is hypothesized to enhance the mechanical and barrier properties of the films through polymer interactions and hydrogen bonding. Our findings confirm that CM incorporation results in films with uniformly smooth surfaces, indicating high compatibility and homogeneity within the starch matrix. Notably, CM improves film transparency and crystallinity. Mechanical assessments show a remarkable elevation in tensile strength, soaring from 5.21 MPa to 12.38 MPa, while elongation at break decreases from 61.73 % to 31.42 %, indicating a trade-off between strength and flexibility. Additionally, water solubility decreases from 57.97 % to 41.40 %, and water vapor permeability is reduced by 30 % with CM loading. These results highlight the role of CM in facilitating the formation of a dense, interconnected polymeric network within the starch matrix. Given the soluble dietary fiber nature of CM, the CS/CM (corn starch/chia mucilage) blended films are expected to be safe for food packaging and applicable as edible films with health benefits.

Intelligent films based on dual-modified starch and microencapsulated Aronia melanocarpa anthocyanins: Functionality, stability and application

This study aims to enhance the physical properties and color stability of anthocyanin-based intelligent starch films. Three dual-modified starches, namely crosslinked-oxidized starch (COS), acetylated distarch phosphate (ADSP), and hydroxypropyl distarch phosphate (HDSP), were utilized as film matrices. Aronia melanocarpa anthocyanins were incorporated through three different pre-treatments (free, spray-drying microencapsulation, and freeze-drying microencapsulation) to assess the prepared films' functionality, stability, and applicability. The results indicate that the ADSP film exhibited an approximately two-fold increase in elongation at break (EAB) compared to native starch film. Specifically, the ADSP film's water contact angle (WCA) reached 90°, demonstrating excellent flexibility and hydrophobicity. Scanning electron microscopy (SEM) revealed stronger interactions between anthocyanins and the film matrix after microencapsulation. Furthermore, after 30 days of exposure to 37 °C heat and light radiation, the freeze-dried anthocyanin-based intelligent film (FDA film) exhibited minimal fading, displaying the highest stability among the tested films. Notably, during beef freshness monitoring, the intelligent films underwent significant color changes as the beef deteriorated. In conclusion, the developed FDA film, with its outstanding stability and responsive pH characteristics, holds immense potential as a novel packaging material for food applications.

Plant betalains-mixed active/intelligent films for meat freshness monitoring: A review of the fabrication parameters

The plant pigments called betalains are nutritionally safe polar compounds. They are subdivided into betaxanthins (having orange to yellow hues) and betacyanins (purple to red violet hues). Betacyanins change color with a change in pH, particularly in the range 6-8 and 9-11. Perishable foods like fish, chicken, beef, pork, and others tend to release total volatile base-nitrogen (TVB-N) during storage or deterioration, which leads to a change in the pH of pH-sensitive materials in the vicinity. pH-sensitive pigment-incorporated polymeric films with inherent active properties (or active/intelligent films) are increasingly being studied as an alternative to synthetic pH indicators to detect the accumulation of TVB-N by changing its color to indicate the stage of perishable food spoilage. There are many methods of developing such films under different conditions using different bio-based biodegradable polymer(s) and biocompatible plasticizer combinations. Among the reported methods, solution casting method has been the preferred one in most studies covered in this review. This method can be carried out under mild conditions. As such, betacyanins-incorporated polymeric films essentially require mild processing conditions because of their heat sensitivity, which will invariably affect the performance in food freshness monitoring. In this review, film fabrication parameters like temperature and duration of dissolution of polymers, plasticizer concentration, pH of the film-forming solution, film drying, and conditioning/aging, have been critically appraised based on the available literature. The lack of studies on the safety of active/intelligent films has been systematically highlighted in this review to focus future studies on this area.

Graphical abstract

Enhancing the production of PHA in Scenedesmus sp. by the addition of green synthesized nitrogen, phosphorus, and nitrogen-phosphorus-doped carbon dots

Plastic consumption has increased globally, and environmental issues associated with it have only gotten more severe; as a result, the search for environmentally friendly alternatives has intensified. Polyhydroxyalkanoates (PHA), as biopolymers produced by microalgae, might be an excellent option; however, large-scale production is a relevant barrier that hinders their application. Recently, innovative materials such as carbon dots (CDs) have been explored to enhance PHA production sustainably. This study added green synthesized multi-doped CDs to Scenedesmus sp. microalgae cultures to improve PHA production. Prickly pear was selected as the carbon precursor for the hydrothermally synthesized CDs doped with nitrogen, phosphorous, and nitrogen-phosphorous elements. CDs were characterized by different techniques, such as FTIR, SEM, ζ potential, UV-Vis, and XRD. They exhibited a semi-crystalline structure with high concentrations of carboxylic groups on their surface and other elements, such as copper and phosphorus. A medium without nitrogen and phosphorous was used as a control to compare CDs-enriched mediums. Cultures regarding biomass growth, carbohydrates, lipids, proteins, and PHA content were analyzed. The obtained results demonstrated that CDs-enriched cultures produced higher content of biomass and PHA; CDs-enriched cultures presented an increase of 26.9% in PHA concentration and an increase of 32% in terms of cell growth compared to the standard cultures.

Influence of Temperatures on Physicochemical Properties and Structural Features of Tamarind Seed Polysaccharide

Due to the high content of impurities such as proteins in tamarind seed polysaccharide (TSP), they must be separated and purified before it can be used. TSP can disperse in cold water, but a solution can only be obtained by heating the mixture. Therefore, it is important to understand the dispersion and dissolution process of TSP at different temperatures to expand the application of TSP. In this study, pasting behavior and rheological properties as a function of temperature were characterized in comparison with potato starch (PS), and their relationship with TSP molecular features and microstructure was revealed. Pasting behavior showed that TSP had higher peak viscosity and stronger thermal stability than PS. Rheological properties exhibited that G' and G'' of TSP gradually increased with the increase in temperature, without exhibiting typical starch gelatinization behavior. The crystalline or amorphous structure of TSP and starch was disrupted under different temperature treatment conditions. The SEM results show that TSP particles directly transformed into fragments with the temperature increase, while PS granules first expanded and then broken down into fragments. Therefore, TSP and PS underwent different dispersion mechanisms during the dissolution process: As the temperature gradually increased, TSP possibly underwent a straightforward dispersion and was then dissolved in aqueous solution, while PS granules initially expanded, followed by disintegration and dispersion.

Characterization of feruloylated arabinoxylan - acorn starch double network gel composite film and its application in postharvest preservation of Agaricus bisporus

To obtain efficient natural food packaging materials, we utilized acorn starch (AS)-based film strengthened by feruloylated arabinoxylan (FAX) gel and additional retrogradation treatment to extend the shelf life of Agaricus bisporus (A. bisporus). Fourier transform infrared spectroscopy (FT-IR), confocal laser scanning microscopy (CLSM), and scanning electron microscopy (SEM) analyses showed that due to the strong hydrogen bonding between FAX and starch molecules, physical crosslinking occurred between FAX and starch molecules in the composite film, and the microstructure became more compact. Thermogravimetric, tensile strength and swelling degree analyses indicate that the composite film exhibits better thermal stability, mechanical properties, and waterproofing compared to the pure AS film. Consequently, after five days of storage, the moisture content of the A. bisporus packaged with our composite film was 7.53 times and 5.73 times higher than that of the control group and the commercially available PEF group, respectively. Moreover, it delayed the respiration or transpiration of A. bisporus (lower weight loss, relative conductivity, MDA content). This packaging film developed with the objective of eco-friendly and biodegradability has considerable application potential in food and other industries.

A-type proanthocyanidins: Sources, structure, bioactivity, processing, nutrition, and potential applications

A-type proanthocyanidins (PAs) are a subgroup of PAs that differ from B-type PAs by the presence of an ether bond between two consecutive constitutive units. This additional C-O-C bond gives them a more stable and hydrophobic character. They are of increasing interest due to their potential multiple nutritional effects with low toxicity in food processing and supplement development. They have been identified in several plants. However, the role of A-type PAs, especially their complex polymeric form (degree of polymerization and linkage), has not been specifically discussed and explored. Therefore, recent advances in the physicochemical and structural changes of A-type PAs and their functional properties during extraction, processing, and storing are evaluated. In addition, discussions on the sources, structures, bioactivities, potential applications in the food industry, and future research trends of their derivatives are highlighted. Litchis, cranberries, avocados, and persimmons are all favorable plant sources. Α-type PAs contribute directly or indirectly to human nutrition via the regulation of different degrees of polymerization and bonding types. Thermal processing could have a negative impact on the amount and structure of A-type PAs in the food matrix. More attention should be focused on nonthermal technologies that could better preserve their architecture and structure. The diversity and complexity of these compounds, as well as the difficulty in isolating and purifying natural A-type PAs, remain obstacles to their further applications. A-type PAs have received widespread acceptance and attention in the food industry but have not yet achieved their maximum potential for the future of food. Further research and development are therefore needed.

Effects of PVA and yerba mate extract on extruded films of carboxymethyl cassava starch/PVA blends for antioxidant and mechanically resistant food packaging

Global concerns over environmental damage caused by non-biodegradable single-use packaging have sparked interest in developing biomaterials. The food packaging industry is a major contributor to non-degradable plastic waste. This study investigates the impact of incorporating different concentrations of polyvinyl alcohol (PVA) and yerba mate extract as a natural antioxidant into carboxymethyl cassava starch films to possibly use as active degradable packaging to enhance food shelf life. Films with starch and PVA blends (SP) at different ratios (SP radios of 100:0, 90:10, 80:20 and 70:30) with and without yerba mate extract (Y) were successfully produced through extrusion and thermoforming. The incorporation of up to 20 wt% PVA improved starch extrusion processing and enhanced film transparency. PVA played a crucial role in improving the hydrophobicity, tensile strength and flexibility of the starch films but led to a slight deceleration in their degradation in compost. In contrast, yerba mate extract contributed to better compost degradation of the blend films. Additionally, it provided antioxidant activity, particularly in hydrophilic and lipophilic food simulants, suggesting its potential to extend the shelf life of food products. Starch-PVA blend films with yerba mate extract emerged as a promising alternative for mechanically resistant and active food packaging.

Developing active and intelligent biodegradable packaging from food waste and byproducts: A review of sources, properties, film production methods, and their application in food preservation

Food waste and byproducts (FWBP) are a global issue impacting economies, resources, and health. Recycling and utilizing these wastes, due to processing and economic constraints, face various challenges. However, valuable components in food waste inspire efficient solutions like active intelligent packaging. Though research on this is booming, its material selectivity, effectiveness, and commercial viability require further analysis. This paper categorizes FWBP and explores their potential for producing packaging from both animal and plant perspectives. In addition, the preparation/fabrication methods of these films/coatings have also been summarized comprehensively, focusing on the advantages and disadvantages of these methods and their commercial adaptability. Finally, the functions of these films/coatings and their ultimate performance in protecting food (meat, dairy products, fruits, and vegetables) are also reviewed systematically. FWBP provide a variety of methods for the application of edible films, including being made into coatings, films, and fibers for food preservation, or extracting active substances directly or indirectly from them (in the form of encapsulation) and adding them to packaging to endow them with functions such as barrier, antibacterial, antioxidant, and pH response. In addition, the casting method is the most commonly used method for producing edible films, but more film production methods (extrusion, electrospinning, 3D printing) need to be tried to make up for the shortcomings of the current methods. Finally, researchers need to conduct more in-depth research on various active compounds from FWBP to achieve better application effects and commercial adaptability.

A Soy Protein-Based Film Based on Chemical Treatment and Microcrystalline Cellulose Reinforcement Obtained from Corn Husk Byproducts

Developing an environmentally friendly soy protein-based film that offers excellent performance has garnered considerable interest while also posing a significant challenge. Herein, we propose the strategy of covalent and noncovalent cross-linking to improve the mechanical properties of the films. First, chemical denaturation was carried out under the combined action of sodium sulfite, sodium dodecyl sulfate, sodium hydroxide, and urea to reshape the structure of the protein to improve the solubility of protein and release active groups. Then, microcrystalline cellulose (MCC) derived from low-cost agro-industrial byproducts (corn husk) was employed to balance the covalent cross-linking reaction between proteins and the noncovalent reaction between MCC and protein. The results indicate that the structure and properties of the soy protein-based films were modified and improved through chemical treatment in conjunction with biomass enhancement. It is concluded that the addition of 1% MCC improves the tensile strength, elastic modulus, water solubility, and water vapor permeability of "MCC-1%" by 64.7, 75.9, 22.7, and 12.9%, respectively. Additionally, the resulting film of "MCC-1%" exhibits better resistance to thermal degradation and improved thermo-stability. However, the elongation at break decreased by increasing the addition of MCC. Thus, this work may provide a simple and affordable approach to preparing a high-performing soy protein-based film.

Starch biopolymer films containing chitosan nanoparticles: A review

Starch biopolymer films incorporated with chitosan nanoparticles (CNP) or starch/CNP films are promising alternatives to non-degradable food packaging materials. The films can be utilized for active food packaging applications because CNP exhibits antimicrobial and antioxidant properties, which can improve food shelf-life. Nonetheless, knowledge of the effects of CNP inclusion on the properties of starch films is not fully elucidated. This paper reviews the influences of various concentrations of CNP, sizes of CNP, and other additives on the mechanical, thermal, barrier, antimicrobial, antioxidant, biodegradability, and cytotoxicity properties of starch/CNP films as well as the mechanisms involved in relation to food packaging applications. The usage of starch/CNP films for active food packaging can help to reduce environmental issues and contribute to food safety and security.

Silver Coordination Polymers Driven by Adamantoid Blocks for Advanced Antiviral and Antibacterial Biomaterials

The development of sustainable biomaterials and surfaces to prevent the accumulation and proliferation of viruses and bacteria is highly demanded in healthcare areas. This study describes the assembly and full characterization of two new bioactive silver(I) coordination polymers (CPs) formulated as [Ag(aca)(μ-PTA)]n·5nH2O (1) and [Ag2(μ-ada)(μ3-PTA)2]n·4nH2O (2). These products were generated by exploiting a heteroleptic approach based on the use of two different adamantoid building blocks, namely 1,3,5-triaza-7-phosphaadamantane (PTA) and 1-adamantanecarboxylic (Haca) or 1,3-adamantanedicarboxylic (H2ada) acids, resulting in the assembly of 1D (1) and 3D (2). Antiviral, antibacterial, and antifungal properties of the obtained compounds were investigated in detail, followed by their incorporation as bioactive dopants (1 wt %) into hybrid biopolymers based on acid-hydrolyzed starch polymer (AHSP). The resulting materials, formulated as 1@AHSP and 2@AHSP, also featured (i) an exceptional antiviral activity against herpes simplex virus type 1 and human adenovirus (HAd-5) and (ii) a remarkable antibacterial activity against Gram-negative bacteria. Docking experiments, interaction with human serum albumin, mass spectrometry, and antioxidation studies provided insights into the mechanism of antimicrobial action. By reporting these new silver CPs driven by adamantoid building blocks and the derived starch-based materials, this study endows a facile approach to access biopolymers and interfaces capable of preventing and reducing the proliferation of a broad spectrum of different microorganisms, including bacteria, fungi, and viruses.

Fundamental investigation of micro-nano cellulose and lignin interaction for transparent paper: Experiment and electrostatic potential calculation

Plastic has significant negative consequences for the environment and human health, demanding greener alternatives. Lignocellulose is a sustainable biomass material, and its paper has been considered as a potential material to replace plastics. Micro-nano lignocellulose, derived from natural plants, possesses a small size and abundant hydrogen bonding capacity. However, there is no clear explanation for the interactions between lignin and micro-nano cellulose, and little understanding of how the interaction can affect the papers' structure and optical properties. Electrostatic potential calculation is a reliable tool to explain non-covalent interactions, and can explore the binding between lignin and micro-nano cellulose. In this paper, kenaf - a non-wood fiber raw material - was employed to prepare micro-nano lignocellulose. The resulting slurry facilitated the production of transparent paper via a simple casting method. The prepared transparent micro-nano paper exhibited high transparency (~90 %), UVA resistance (~80 %), and hydrophobicity (~114°). More importantly, the electrostatic potential calculation demonstrates the inherent relationship between structure and performance, providing practical knowledge for constructing film materials.

A review of starch-based biocomposites reinforced with plant fibers

Renewable and biodegradable resources have gained increasing attention as promising alternatives to synthetic plastics. Among the diverse raw materials employed in bioplastics production, starch emerges as an attractive, low-cost, and largely available source. However, the inherent properties of starch-based materials often limit their utility across various applications, necessitating strategic modifications to enhance their performance. A common approach to boost these materials involves incorporating natural fillers into biopolymer matrices. Incorporating natural fibers within starch matrices enables the development of biocomposites with improved properties while retaining their renewable and biodegradable characteristics. This review briefly addresses fundamental aspects of starch structure, obtention, and processing, as well as the main pre-treatments of natural fibers and processing methods currently applied to produce starch-based composites. It also highlights the most recent advances in this field, elucidates the effect of the incorporation of fibers on the biocomposite properties, and discusses the critical parameters affecting the synergic combination between starch and fibers.

Improving water resistance and mechanical properties of starch-based films by incorporating microcrystalline cellulose in a dynamic network structure

The widespread use of starch-based films is hindered by inadequate tensile strength and high water sensitivity. To address these limitations, a novel starch film with a dynamic network structure was produced via the dehydration-condensation reaction of N, N'-methylene diacrylamide (MBA) and microcrystalline cellulose (MCC). The improvement in mechanical properties was enhanced by the incorporation of MCC, which was achieved through intermolecular hydrogen bonding and chemical crosslinking. To verify the interactions among MCC, MBA, and starch, x-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR), and x-ray diffraction (XRD) were conducted. The results established the predicted interactions. The dynamic network structure of the film reduced the water absorption capacity (WAC) of starch and MCC hydroxyl groups, as confirmed by differential scanning calorimeter (DSC) and dynamic mechanical thermal analysis (DMTA). These analyses showed a restriction in the mobility of starch chains, resulting in a higher glass transition temperature (Tg) of 69.26 °C. The modified starch films exhibited excellent potential for packaging applications, demonstrating a higher contact angle (CA) of 89.63°, the lowest WAC of 4.73 g/g, and the lowest water vapor transmission rate (WVTR) of 13.13 g/m2/d, along with improved mechanical properties and identical light transmittance compared to pure starch films.

Development of cassava starch-based films incorporated with phenolic compounds produced by an Amazonian fungus

Drug-release systems have attracted attention over the last few years since they can be used as a substitute for traditional methods of drug delivery. These have the advantage of being directly administered at the treatment site and can maintain the drug at adequate levels for a longer period, thus increasing their efficacy. Starch-based films are interesting candidates for use as matrices for drug release, especially due to starch's non-toxic properties and its biocompatibility. Endophytic fungi are an important source of bioactive molecules, including secondary metabolites such as phenolic compounds with antioxidant activity. In the present study, cassava starch-based films were developed to act as release systems of phenolic compounds with antioxidant activity. The Amazonian endophytic fungus Aspergillus niger MgF2 was cultivated in liquid media, and the fungal extract was obtained by liquid-liquid partition with ethyl acetate. The starch-based films incorporated with the fungal extract were characterized in regards to their physicochemical properties. The release kinetics of the extract from the film and its antioxidant and cytotoxic properties were also evaluated. The films incorporated with the extract presented maximum release after 25 min at 37 °C and pH 6.8. In addition, it was observed that the antioxidant compounds of the fungal extract maintain their activity after being released from the film, and were non-toxic. Therefore, considering the promising physicochemical properties of the extract-incorporated films, and their considerable antioxidant capacity, the films demonstrate great biotechnological potential with diverse applications in the pharmacological and cosmetic industries.

A Review of Natural Polysaccharides: Sources, Characteristics, Properties, Food, and Pharmaceutical Applications

Natural polysaccharides, which are described in this study, are some of the most extensively used biopolymers in food, pharmaceutical, and medical applications, because they are renewable and have a high level of biocompatibility and biodegradability. The fundamental understanding required to properly exploit polysaccharides potential in the biocomposite, nanoconjugate, and pharmaceutical industries depends on detailed research of these molecules. Polysaccharides are preferred over other polymers because of their biocompatibility, bioactivity, homogeneity, and bioadhesive properties. Natural polysaccharides have also been discovered to have excellent rheological and biomucoadhesive properties, which may be used to design and create a variety of useful and cost-effective drug delivery systems. Polysaccharide-based composites derived from natural sources have been widely exploited due to their multifunctional properties, particularly in drug delivery systems and biomedical applications. These materials have achieved global attention and are in great demand because to their biochemical properties, which mimic both human and animal cells. Although synthetic polymers account for a substantial amount of organic chemistry, natural polymers play a vital role in a range of industries, including biomedical, pharmaceutical, and construction. As a consequence, the current study will provide information on natural polymers, their biological uses, and food and pharmaceutical applications.

Bioactive properties of clove (Syzygium aromaticum) essential oil nanoemulsion: A comprehensive review

Syzygium aromaticum, commonly called clove, is a culinary spice with medical uses. Clove is utilized in cosmetics, medicine, gastronomy, and agriculture due to its abundance of bioactive components such as gallic acid, flavonoids, eugenol acetate, and eugenol. Clove essential oil has been revealed to have antibacterial, antinociceptive, antibacterial activities, antifungal, and anticancerous qualities. Anti-inflammatory chemicals, including eugenol and flavonoids, are found in clove that help decrease inflammation and alleviate pain. The anti-inflammatory and analgesic qualities of clove oil have made it a popular natural cure for toothaches and gum discomfort. Due to its therapeutic potential, it has been used as a bioactive ingredient in coating fresh fruits and vegetables. This review article outlines the potential food processing applications of clove essential oil. The chemical structures of components, bioactive properties, and medicinal potential of clove essential oil, including phytochemical importance in food, have also been thoroughly addressed.

Evaluation of physicochemical properties of citric acid crosslinked starch elastomers reinforced with silicon dioxide

Thermoplastic starch (TPS), derived from renewable resources, offers advantages such as biodegradability and lower production costs compared to petroleum-based plastics. However, its limited mechanical properties pose a challenge for broader applications. This research aims to explore the potential of enhancing the mechanical and barrier properties of TPS films through the incorporation of silicon dioxide as a reinforcement filler and citric acid as a crosslinking agent. By introducing silicon dioxide as a reinforcement filler, the mechanical strength of the TPS films is expected to be improved. Additionally, the incorporation of citric acid as a crosslinking agent is anticipated to enhance the barrier properties of the films. The combination of these additives holds promise for creating TPS films with improved performance, contributing to the development of sustainable and environmentally friendly materials in various industries. The results reveal that SiO2 improves the stiffness of the films at lower concentrations but causes brittleness at higher concentrations. In contrast, citric acid crosslinked films exhibit improved flexibility and density. Scanning electron microscopy demonstrates the morphological changes in the films, with SiO2 affecting surface roughness and aggregate formation. SiO2 reduces film thickness and transparency, while citric acid enhances water resistance and barrier properties. X-ray diffraction analysis shows a reduction in crystallinity due to the plasticization process. Fourier-transform infrared spectroscopy highlights chemical changes and antimicrobial activity is observed with citric acid against specific bacteria. The soil burial test reveals that citric acid crosslinked films exhibit slower degradation due to antimicrobial properties. The combination of SiO2 reinforcement and citric acid crosslinking enhances the overall performance of the films, promising sustainable and environmentally friendly materials for various applications.

Characterization of starch film incorporating Hom Nil rice extract for food packaging purposes

Poor water resistance, mechanical properties and stability limit the food packaging applications of starch films. Since the properties of starch films are improved by incorporating phenolic compounds and anthocyanins from natural plant extracts, Hom Nil rice (HN) extract was incorporated into cassava starch solution to produce a starch-based packaging film. We evaluated the extraction condition to optimize the total phenolic and anthocyanin contents of the HN extract. The optimal ratio of ethanol solution:Hom Nil rice powder was 5:1 v/w% and the optimal extraction time was 60 min. The influence of HN extract on the viscosity of the film solution and the properties of the obtained films were investigated. The results showed that the HN extract increased the viscosity of the starch solution. A film containing 8 wt% of HN extract produced the highest water contact angle and tensile strength, and hindered the retrogradation process. Therefore, cassava starch film modified with the proposed HN extract has the potential to be used as a food packaging material.

Effect of emulsifiers on the properties of corn starch films incorporated with Zanthoxylum bungeanum essential oil

The use of natural and safe ingredients in green food packaging material is a hot research topic. This study investigated the effect of different emulsifiers on starch film properties. Three types of emulsifiers, including Tween 80 as a small-molecule surfactant, sodium caseinate (CAS), whey protein isolate (WPI), and gelatin (GE) as macromolecule emulsifiers, whey protein isolate fibril (WPIF) as a particle emulsifier, were utilized to prepare Zanthoxylum bungeanum essential oil (ZBO) emulsions. The mechanical, physical, thermal, antibacterial properties, microstructure and essential oil release of starch films were investigated. CAS-ZBO nanoemulsion exhibited the smallest particle size of 198.6 ± 2.2 nm. The film properties changed with different emulsifiers. CAS-ZBO film showed the highest tensile strength value. CAS-ZBO and WPIF-ZBO films exhibited lower water vapor permeability than Tween-ZBO. CAS-ZBO film showed good dispersion of essential oil, the slowest release rate of essential oils in all food simulants, and the best antibacterial effect against Staphylococcus aureus and Listeria monocytogenes. The films composed of CAS-ZBO nanoemulsion, corn starch, and glycerol are considered more suitable for food packaging. This work indicated that natural macromolecule emulsifiers of CAS and WPIF are expected to be used in green food packaging material to offer better film properties.

Construction of intelligent drug delivery system based on polysaccharide-derived polymer micelles: A review

Micelles are nanostructures developed via the spontaneous assembly of amphiphilic polymers in aqueous systems, which possess the advantages of high drug stability or active-ingredient solubilization, targeted transport, controlled release, high bioactivity, and stability. Polysaccharides have excellent water solubility, biocompatibility, and degradability, and can be modified to achieve a hydrophobic core to encapsulate hydrophobic drugs, improve drug biocompatibility, and achieve regulated delivery of the loaded drug. Micelles drug delivery systems based on polysaccharides and their derivatives show great potential in the biomedical field. This review discusses the principles of self-assembly of amphiphilic polymers and the formation of micelles; the preparation of amphiphilic polysaccharides is described in detail, and an overview of common polysaccharides and their modifications is provided. We focus on the review of strategies for encapsulating drugs in polysaccharide-derived polymer micelles (PDPMs) and building intelligent drug delivery systems. This review provides new research directions that will help promote future research and development of PDPMs in the field of drug carriers.

Pre-gelatinized high-amylose starch enables easy preparation of flexible and antimicrobial composite films for fresh fruit preservation

While high-amylose starch (HAS) possesses advantageous properties such as high resistant starch content and favorable mechanical attributes, its gelatinization constraints have limited its applicability. This study enhances its versatility by focusing on pre-gelatinized (PG) HAS with exceptional rehydratability, achieved by disorganizing native HAS granules (with amylose contents of 55 % and 68 %, respectively) using a 33 % CaCl2 solution, followed by water-ethanol precipitation and freeze-drying. The resulting PG-HAS exhibited elevated amylose content (61 % and 75 %) with minimal changes in amylose molecular weight. PG-HAS displayed superior water-absorption index (WAI) and water-soluble index (WSI) compared to native HAS, further improved by 2 % CaCl2 solution incorporation. Furthermore, composite films were prepared by mixing PG-HAS with PVA at a 6:4 (w/w) ratio. The PG-G50 (61 % amylose content)/PVA composite film exhibited remarkable elongation (131.1 ± 5.4 %), nearly three times that of a normal corn starch (NCS, with 27 % amylose)/PVA film, attributed to improved starch dispersity and higher amylose content. Nonetheless, the PG-G70 (75 % amylose content)/PVA film at the same ratio showed lower elongation (54.7 ± 8.0 %), potentially due to strong cohesive forces between amylose chains that impede starch-PVA interactions. Moreover, the PG-HAS/PVA composite films, enriched with antibacterial agents, demonstrated effective antibacterial properties with a gradual and sustained release of active compounds. Notably, the PG-G50/PVA/tannic acid (TA) film effectively preserved fresh apple slices by inhibiting bacteria growth and preventing browning. These findings underscore the excellent rehydration of PG-HAS and its potential as an inner packaging material for irregularly shaped foods, such as sliced fruits or meats, due to its nontoxic nature, softness and flexibility, which allows the film to maintain close contact with food surfaces.

Hybrid green bionanocomposites based on chitosan/starch/gelatin and metallic nanoparticles for biological applications

Multicomponent composites based on natural biopolymers: chitosan, starch and gelatin in two different ratios (0.5:1:1 and 1:1:1) were in situ crosslinked by intermolecular interactions and used as matrices for zinc oxide and magnetite fillers. The bionanocomposite films have been evaluated by spectral and microscopy methods: Fourier-Transform Infrared spectrometry (FT-IR), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) confirming the electrostatic and hydrogen bonding interactions between the components of the polymeric matrices and the inorganic fillers and the crosslinking process. AFM and SEM images showed a compact, non-porous and homogenous morphology of the hybrid films, proving a good miscibility of the blends. At lower concentrations of embedded filler, the composites were less hardened and more ductile due to the interaction with the polymeric matrix. Increased amounts of inorganic NPs led to the reduced mechanical properties of the prepared materials and increased thermal stability. The bionanocomposites revealed a similar behavior of the dielectric constant with frequency and increased values at higher temperatures. The wettability of the films' surface and the values of the water sorption capacity revealed a slight hydrophilicity of the bionanocomposites as compared with the initial matrices. The biocompatibility, evaluated by means of the surface free energy components and the interfacial tension with blood, and the hemolysis analysis demonstrated that the bionanocomposites possess a low risk of thrombosis, being promising materials for in vivo biomedical applications.