Energetic neutral N2 atoms treatment on the kithul (Caryota urens) starch biodegradable film: Physico-chemical characterization

Mechanistic applications of low-temperature plasma in starch-based biopolymer film: A review

The substitution of traditional packaging with bio-based edible films has emerged as a new research direction. The starch biopolymer films currently studied by researchers exhibit issues such as inadequate physical properties, barrier performance, mechanical strength, and biological activity. Consequently, a range of advanced techniques are employed to enhance the properties of biopolymer films. Low-temperature plasma stands out as an emerging multi-functional non-thermal green molecular surface modification technology that has been particularly effective in enhancing starch biopolymer films. Furthermore, owing to its non-thermal characteristics, low-temperature plasma is particularly suitable for heat-sensitive materials. Consequently, this study aims to investigate the impact of low-temperature plasma technology on enhancing the properties of biopolymer film substrates, elucidate its mechanisms of action on starch films and starch composite films, refine methods for modifying biopolymer films, and conduct a rational analysis of any contradictions.

Dual-functional Zn@melanin nanoparticles for enhanced antibacterial activity and prolonged fruit preservation

Mitigating food spoilage from microbial infections remains a critical challenge in food preservation. Although Zn2+ ions are used as chemical bactericides, their use alone often requires high doses. A novel nanomaterial, Zn@MNPs, combining photothermal properties with the controlled release of Zn2+, was synthesized through a coordination of Zn2+ with melanin nanoparticles (MNPs) derived from cuttlefish ink. Zn@MNPs were capable of attaching onto the bacterial surfaces, enabling high-efficiency release of Zn2+ under mildly acidic conditions typically associated with bacterial infections. This leads to sustained antibacterial activity, causing bacterial membrane rupture and leakage of intracellular components. Incorporating Zn@MNPs into polyvinyl alcohol (PVA)-based films improved their ability to block UV light and reduce oxygen and water vapor permeability. These films effectively reduced dehydration, preserved nutritional content, and extended fruit shelf life. This study highlights the potential of Zn@MNPs-based PVA films as biodegradable, bioactive packaging materials for enhancing food preservation and safety.

Preparation and characterization of bioplastic film from the green seaweed Halimeda opuntia

Protein-rich seaweeds are regarded as having commercial significance due to their numerous industrial applications. The green seaweed Halimeda opuntia was used during this study for the preparation of bioplastic film. A thin bioplastic film with better physical and mechanical properties was produced by optimizing the ratio of polyvinyl alcohol (PVA) to seaweed biomass. The films obtained were characterized by their thickness, tensile strength, elongation at break, Young's modulus, moisture absorption resistance, and solubility. To evaluate the composition and potential for chemical reactions of the films, an FTIR spectroscopy examination was conducted. Whereas TG-DTA and AFM were performed on films with high mechanical properties. The bioplastic film produced when algae percent was tripled in PVA concentration had better physical and mechanical characteristics, and the bioplastic films degraded in the environment within a short time. According to the current study, seaweed might serve as an alternative source for the production of bioplastic, which could help minimize the use of non-biodegradable plastics.

Enhanced properties of non-starch polysaccharide and protein hydrocolloids through plasma treatment: A review

Hydrocolloids are important ingredients in food formulations and their modification can lead to novel ingredients with unique functionalities beyond their nutritional value. Cold plasma is a promising technology for the modification of food biopolymers due to its non-toxic and eco-friendly nature. This review discusses the recent published studies on the effects of cold plasma treatment on non-starch hydrocolloids and their derivatives. It covers the common phenomena that occur during plasma treatment, including ionization, etching effect, surface modification, and ashing effect, and how they contribute to various changes in food biopolymers. The effects of plasma treatment on important properties such as color, crystallinity, chemical structure, rheological behavior, and thermal properties of non-starch hydrocolloids and their derivatives are also discussed. In addition, this review highlights the potential of cold plasma treatment to enhance the functionality of food biopolymers and improve the quality of food products. The mechanisms underlying the effects of plasma treatment on food biopolymers, which can be useful for future research in this area, are also discussed. Overall, this review paper presents a comprehensive overview of the current knowledge in the field of cold plasma treatment of non-starch hydrocolloids and their derivatives and highlights the areas that require further investigation.

Mairá-Potato (Casimirella sp.): Botanical, Food, Pharmacological, and Phytochemical Aspects

Millions of people in the world live in food insecurity, so identifying a tuber with characteristics capable of meeting the demand for food and also identifying active compounds that can be used to minimize harm to human health is of great value. The aim was to carry out a review based on systematic review tools and the main objective was to seek information on botanical, food, pharmacological, and phytochemical aspects of Casimirella sp. and propose possible applications. This review showed papers that addressed botanical, food, pharmacological, and phytochemical aspects of the Mairá-potato and presented suggestions for using this tuber allied to the information described in the works found in the Google Academic, Scielo, Science Direct, Scopus, PubMed, and Web of Science databases. This review synthesized knowledge about the Mairá-potato that can contribute to the direction of further research on the suggested technological applications, both on the use of this tuber as a polymeric material and its use as biomaterial, encapsulation, bioactive use, and 3D printing, because this work collected information about this non-conventional food plant (PANC) that shows great potential for use in various areas of study.

Hierarchical structural modification of starch via non-thermal plasma: A state-of-the-art review

The hierarchical architecture of natural and processed starches with different surface and internal structures determines their final physicochemical properties. However, the oriented control of starch structure presents a significant challenge, and non-thermal plasma (cold plasma, CP) has gradually been used to design and tailor starch macromolecules, though without clear illustration. In this review, the multi-scale structure (i.e., chain-length distribution, crystal structure, lamellar structure, and particle surface) of starch is summarized by CP treatment. The plasma type, mode, medium gas and mechanism are also illustrated, as well as their sustainable food applications, such as in food taste, safety, and packaging. The effects of CP on the chain-length distribution, lamellar structure, amorphous zone, and particle surface/core of starch includes irregularity due to the complex of CP types, action modes, and reactive conditions. CP-induced chain breaks lead to short-chain distributions in starch, but this rule is no longer useful when CP is combined with other physical treatments. The degree but not type of starch crystals is indirectly influenced by CP through attacking the amorphous region. Furthermore, the CP-induced surface corrosion and channel disintegration of starch cause changes in functional properties for starch-related applications.

Dulong People's Traditional Knowledge of Caryota obtusa (Arecaceae): a Potential Starch Plant with Emphasis on Its Starch Properties and Distribution Prediction

The greatest global challenge is to ensure that all people have access to adequate and nutritious food. Wild edible plants, particularly those that provide substitutes for staple foods, can play a key role in enhancing food security and maintaining a balanced diet in rural communities. We used ethnobotanical methods to investigate traditional knowledge on Caryota obtusa, a substitute staple food plant of the Dulong people in Northwest Yunnan, China. The chemical composition, morphological properties, functional, and pasting properties of C. obtusa starch were evaluated. We used MaxEnt modeling to predict the potential geographical distribution of C. obtusa in Asia. Results revealed that C. obtusa is a vital starch species with cultural significance in the Dulong community. There are large areas suitable for C. obtusa in southern China, northern Myanmar, southwestern India, eastern Vietnam, and other places. As a potential starch crop, C. obtusa could substantially contribute to local food security and bring economic benefit. In the future, it is necessary to study the breeding and cultivation of C. obtusa, as well as the processing and development of starch, to solve long-term and hidden hunger in rural areas.

Investigation of Morphological, Chemical, and Thermal Properties of Biodegradable Food Packaging Films Synthesised by Direct Utilisation of Cassava (Monihot esculanta) Bagasse

The utilisation of edible sources of starch such as corn, wheat, potato, and cassava has become the common approach to develop biodegradable food packaging. However, the future food security issue from the wide application of such edible starch sources has become a major concern. Consequently, exploring non-edible sources of starch for starch-based biodegradable food packaging and their property enhancement have become one of the common research interests. Although there has been a great potentials of synthesising biodegradable food packaging by direct utilisation of agro-industrial waste cassava bagasse, there have been very limited studies on this. In this context, the current study investigated the potential of developing biodegradable food packaging by directly using cassava bagasse as an alternative matrix. Two film-forming mixtures were prepared by incorporating glycerol (30% and 35%), powdered cassava bagasse and water. The films were hot-pressed at 60 °C, 100 °C, and 140 °C temperatures under 0.28 t pressure for 6 min. The best film-forming mixture and temperature combination was further tested with 0.42 t and 0.84 t pressures, followed by analysing their morphology, functional group availability and the thermal stability. Accordingly, application of 35% glycerol, with 100 °C, 0.42 t temperature and pressure, respectively, were found to be promising for film preparation. The absence of starch agglomerates in film surfaces with less defects suggested satisfactory dispersion and compatibility of starch granules and glycerol. The film prepared under 0.42 t exhibited slightly higher thermal stability. Synthesised prototypes of food packaging and the obtained characterisation results demonstrated the high feasibility of direct utilisation of cassava bagasse as an alternative, non-edible matrix to synthesise biodegradable food packaging.

Development and Characterization of the Biodegradable Film Derived from Eggshell and Cornstarch

In the current study, cornstarch (CS) and eggshell powder (ESP) were combined using a casting technique to develop a biodegradable film that was further morphologically and physicochemically characterized using standard methods. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the morphology of the ESP/CS film, and the surface of the film was found to have a smooth structure with no cracks, a spherical and porous irregular shape, and visible phase separation, which explains their large surface area. In addition, the energy dispersive X-ray (EDX) analysis indicated that the ESP particles were made of calcium carbonate and the ESP contained carbon in the graphite form. Fourier Transform Infrared Spectroscopy indicated the presence of carbonated minerals in the ESP/CS film which shows that ESP/CS film might serve as a promising adsorbent. Due to the inductive effect of the O–C–O bond on calcium carbonate in the eggshell, it was discovered that the ESP/CS film significantly improves physical properties, moisture content, swelling power, water solubility, and water absorption compared to the control CS film. The enhancement of the physicochemical properties of the ESP/CS film was principally due to the intra and intermolecular interactions between ESP and CS molecules. As a result, this film can potentially be used as a synergistic adsorbent for various target analytes.

Current Research and Applications of Starch-Based Biodegradable Films for Food Packaging

The use of biodegradable packaging material as an alternative to conventional petrochemical-based polymers is based on the environmental issues associated with conventional materials. This review aims to update the existing knowledge regarding the application of starch-based biodegradable films for food packaging. From the review, it was evident that starch stands out among biopolymers due to its abundance and cost effectiveness. This review is the first of its kind, having reviewed over 100 articles/publications on starch-based biodegradable films, consolidating their current state of research and their applications for food packaging; therefore, this review provides an insight into the utilization of nanomaterials to improve the shelf life of packaging of food.

Effect of Thermal Pretreatments on Phosphorylation of Corypha umbraculifera L. Stem Pith Starch: A Comparative Study Using Dry-Heat, Heat-Moisture and Autoclave Treatments

Talipot starch, a non-conventional starch source with a high yield (76%) from the stem pith of talipot palm (Corypha umbraculifera L.) was subjected to three different thermal treatments (dry-heat, heat-moisture and autoclave treatments) prior to phosphorylation. Upon dual modification of starch with thermal treatments and phosphorylation, the phosphorous content and degree of crosslinking significantly increased (p ≤ 0.05) and was confirmed by the increased peak intensity of P=O and P-O-C stretching vibrations compared to phosphorylated talipot starch in the FT-IR spectrum. The highest degree of crosslinking (0.00418) was observed in the autoclave pretreated phosphorylated talipot starch sample. Thermal pretreatment remarkably changed the granule morphology by creating fissures and grooves. The amylose content and relative crystallinity of all phosphorylated talipot starches significantly decreased (p ≤ 0.05) due to crosslinking by the formation of phosphodiester bonds, reducing the swelling power of dual-modified starches. Among all modified starches, dry-heat pretreated phosphorylated starch gel showed an improved light transmittance value of 28.4%, indicating reduced retrogradation tendency. Pasting and rheological properties represented that the thermal pretreated phosphorylated starch formed stronger gels that improved thermal and shear resistance. Autoclave treatment before phosphorylation of talipot starch showed the highest resistant starch content of 48.08%.

Hydrothermal modifications of nonconventional kithul (Caryota urens) starch: physico-chemical, rheological properties and in vitro digestibility

Effect of hydrothermal modifications (autoclaving, annealing and heat moisture treatment) on physico-chemical, rheological properties and in vitro digestibility of kithul starch was studied. Annealing and heat moisture treatment decreased swelling index, solubility and increased crystalline properties as compared with autoclaving. Autoclaving, annealing and heat moisture treatment caused significant morphological damages such as large holes and fissures on the kithul starch, in addition, granules changed from oval to donut shape. Heat moisture treatment formed higher number of agglomerated starch granules. Light transmittance decreased after hydrothermal modifications. Autoclaving and annealing increased the pasting viscosities (except break down viscosity) of kithul starch. A significant increase (p ≤ 0.05) in peak temperature, conclusion temperature and enthalpy was found in annealed and heat moisture treated kithul starches. The digestibility of kithul starch decreased with increasing resistant starch after annealing and heat moisture treatment. Autoclaved, annealed and heat moisture treated kithul starches exhibited higher value of storage modulus (G') and loss modulus (G″) than native kithul starch. It entail to higher firmness of modified starch gel. The current study showed that the remarkable changes formed by hydrothermal modifications increased the industrial acceptance of kithul starch.