Exploration of multifunctional properties of garlic skin derived cellulose nanocrystals and extracts incorporated chitosan biocomposite films for active packaging application

Sausage Preservation Using Films Composed of Chitosan and a Pickering Emulsion of Essential Oils Stabilized with Waste-Jujube-Kernel-Derived Cellulose Nanocrystals

The purpose of this study was to prepare Pickering emulsions stabilized by waste jujube kernel cellulose nanocrystals (CNC) using composite essential oils (EOs) (i.e., cinnamon essential oil [CIN] combined with clove essential oil [CL]). The Pickering emulsions were blended with chitosan (CS) to generate a composite film (CS/CNC/EOs Pickering emulsions). We evaluated the mechanical properties, barrier properties, and microstructures of CS/CNC/EOs bio-based packaging films containing different concentrations of EOs. In addition, the fresh-keeping effects of the composite membranes on beef sausages were evaluated over a 12-day storage period. Notably, the EOs exhibited good compatibility with CS. With the increase in the EOs concentration, the droplet size increased, the composite films became thicker, the elongation at break decreased, the tensile strength increased, and the water vapor permeability decreased. When the composite films were used for preserving beef sausages, the antioxidant and antibacterial activity of the membranes improved as the concentration of EOs increased, effectively prolonging the shelf life of the sausages. Composite membranes with an EOs concentration of 2% exerted the best fresh-keeping effects. Overall, owing to their antioxidant and antimicrobial properties, the bio-based composite films prepared using CS/CNC/EOs Pickering emulsions demonstrated immense potential for application in the packaging of meat products.

Research progress on natural preservatives of meat and meat products: classifications, mechanisms and applications

Meat and meat products are highly susceptible to contamination by microorganisms and foodborne pathogens, which cause serious economic losses and health hazards. The large consumption and waste of meat and meat products means that there is a need for safe and effective preservation methods. Furthermore, toxicological aspects of chemical preservation techniques related to major health problems have sparked controversies and have prompted consumers and producers to turn to natural preservatives. Consequently, natural preservatives are being increasingly used to ensure the safety and quality of meat products as a result of customer preferences and biological efficacy. However, information on the current status of these preservatives is scattered and a comprehensive review is lacking. Here, we review current knowledge on the classification, mechanisms of natural preservatives and their applications in the preservation of meat and meat products, and also discuss the potential of natural preservatives to improve the safety of meat and meat products. The current status and the current research gaps in the extraction, application and controlled-release of natural antibacterial agents for meat preservation are also discussed in detail. This review may be useful to the development of efficient food preservation techniques in the meat industry. © 2024 Society of Chemical Industry.

Fabrication of Highly Efficient ZIF-8@PEI Monoliths for CO2 Capture Using Phosphorylated Cellulose Nanofiber as a Binder

This study involves the synthesis and comparison of zeolitic imidazolate frameworks (ZIFs), specifically ZIF-8 and ZIF-67 pristine with a commercial zeolite, emphasizing their CO2 affinity and sorption capability. To overcome challenges persisting in the handling and integration of these materials into industrial adsorption processes, particularly when limited to microcrystalline fine powders, we present herein an innovative manufacturing method to produce standalone monolithic supports. This process involves pseudoplastic paste formulations utilizing polyethylenimine (PEI) as a coagulant and locally fabricated phosphorylated cellulose nanofiber (PCNF) as a binding agent. Rheological investigation was conducted to anticipate the required shaping and design by means of paste flowability, consistency, and stiffness. XRD and FTIR results confirm the preservation of crystalline structure and the occurrence of amine functionalization associated with the presence of PEI, respectively. The proposed method significantly enhances the CO2 adsorption performance of the produced ZIF-8 monolith in comparison with that reached when using the pristine material, achieving a capacity of 1.25-2 mmol·g-1 at 30 °C under dry conditions in a pressure range of 1-13 bar, respectively. In other words, this work clearly highlights an effective applicability of the ZIF-8 monolith as an innovative sorbent for further designing CO2 capture industrial setups.

Application of Natural Functional Additives for Improving Bioactivity and Structure of Biopolymer-Based Films for Food Packaging: A Review

The global trend towards conscious consumption plays an important role in consumer preferences regarding both the composition and quality of food and packaging materials, including sustainable ones. The development of biodegradable active packaging materials could reduce both the negative impact on the environment due to a decrease in the use of oil-based plastics and the amount of synthetic preservatives. This review discusses relevant functional additives for improving the bioactivity of biopolymer-based films. Addition of plant, microbial, animal and organic nanoparticles into bio-based films is discussed. Changes in mechanical, transparency, water and oxygen barrier properties are reviewed. Since microbial and oxidative deterioration are the main causes of food spoilage, antimicrobial and antioxidant properties of natural additives are discussed, including perspective ones for the development of biodegradable active packaging.

Evaluation of Starch-Garlic Husk Polymeric Composites through Mechanical, Thermal, and Thermo-Mechanical Tests

The present work evaluates the influence of different properties of composite materials from natural sources. Films were prepared using the evaporative casting technique from corn starch reinforced with a waste material such as garlic husk (GH), using glycerin as a plasticizer. The results of the syntheses carried out demonstrated the synergy between these materials. In the morphological analysis, the compatibility and adequate dispersion of the reinforcer in the matrix were confirmed. Using Fourier transform infrared spectroscopy (FTIR), the interaction and formation of bonds between the matrix and the reinforcer were confirmed by the presence of some signals such as S-S and C-S. Similarly, thermogravimetric analysis (TGA) revealed that even at low concentrations, GH can slightly increase the decomposition temperature. Finally, from the results of dynamic mechanical analysis (DMA), it was possible to identify that the storage modulus increases significantly, up to 115%, compared to pure starch, especially at low concentrations of the reinforcer.

Analysis of Rumen Degradation Characteristics, Attached Microbial Community, and Cellulase Activity Changes of Garlic Skin and Artemisia argyi Stalk

The purpose of this study was to study the chemical composition, rumen degradation characteristics, surface attached microbial community and cellulase activity of garlic skin (GS) and Artemisia argyi stalk (AS), in order to explain their feeding value. Four 14-month-old healthy Min Dong male goats with permanent rumen fistula were selected as experimental animals. The rumen degradation characteristics of GS and AS were determined by using the nylon bag method, and the bacterial composition, cellulase activity and their relationship on the surface of the two groups were analyzed with high-throughput sequencing of 16S rRNA gene. The results showed that in GS and AS, the effective degradation rate (ED) values of dry matter (DM) were 42.53% and 37.12%, the ED values of crude protein (CP) were 37.19% and 43.38%, the ED values of neutral detergent fiber (NDF) were 36.83% and 36.23%, and the ED values of acid detergent fiber (ADF) were 33.81% and 34.77%. During rumen degradation, the richness and evenness of bacteria attached to the AS surface were higher. At the phylum level, Bacteroidetes and Firmicutes were always the main rumen bacteria in the two groups. At the genus level, fiber-degrading bacteria such as Prevotella, Treponema, and Ruminococcus showed higher levels in GS (p < 0.05). Compared with GS, the activity of β-glucosidase (BG enzyme), endo-β-1,4-glucanase (C1 enzyme), exo-β-1,4-glucanase (Cx enzyme) and neutral xylanase (NEX enzyme) attached to AS surface showed a higher trend. Correlation analysis showed that the relative abundance of Succinivibrio and Rikenellaceae_RC9_gut_group was positively correlated with the rumen degradability of nutrients in GS, and the relative abundance of Christensenellaceae R-7_group, Succinivibrio and Ruminococcus was positively correlated with the rumen degradability of nutrients in AS. The conclusion of this study shows that AS has more potential to become ruminant roughage than GS. In addition, this study also revealed the relationship between cellulase activity and bacteria, which provided new information for us to better analyze the effects of GS and AS on the rumen of ruminants and provided an important theoretical basis for the development and utilization of agricultural by-products.

Development of bio-based PLA/cellulose antibacterial packaging and its application for the storage of shiitake mushroom

This study presents the extraction of cellulose from water bamboo byproducts to prepare polylactic acid (PLA)/cellulose antibacterial packaging material. The cellulose was modified using a silane coupling agent, which improved the interfacial compatibility between cellulose and PLA. Upon coating the PLA onto the modified cellulose sheet, the water contact angle of the composite material increased from 11.42° to 132.12° and the water absorption rate decreased from 182.52% to 55.71%, which improved the water resistance performance of the material. The addition of cinnamaldehyde in the PLA layer imparted antibacterial activity to the PLA/cellulose packaging material. This packaging material effectively inhibited the mycelial growth and spore germination of Aspergillus niger and Trichoderma harzianum isolated from shiitake mushroom. Additionally, the study investigated the effects of the composite on the postharvest quality of shiitake mushroom. Overall, the packaging material contributed to shiitake mushroom storage and can be applied to other perishable food products.

Recent advances in cellulose nanocrystals-based antimicrobial agents

Over the past five years, there has been growing interest in the design of modified cellulose nanocrystals (CNCs) as nanoscale antimicrobial agents in potential end-user applications such as food preservation/packaging, additive manufacturing, biomedical and water purification. The interest of applying CNCs-based antimicrobial agents arise due to their abilities to be derived from renewable bioresources and their excellent physicochemical properties including rod-like morphologies, large specific surface area, low toxicity, biocompatibility, biodegradability and sustainability. The presence of ample surface hydroxyl groups further allows easy chemical surface modifications for the design of advanced functional CNCs-based antimicrobial materials. Furthermore, CNCs are used to support antimicrobial agents that are subjected to instability issues. The current review summarizes recent progress in CNC-inorganic hybrid-based materials (Ag and Zn nanoparticles, other metal/metal oxide) and CNC-organic hybrid-based materials (polymers, chitosan, simple organic molecules). It focuses on their design, syntheses and applications with a brief discussion on their probable modes of antimicrobial action whereby the roles of CNCs and/or the antimicrobial agents are highlighted.

Fabrication of Bio-Nanocomposite Packaging Films with PVA, MMt Clay Nanoparticles, CNCs, and Essential Oils for the Postharvest Preservation of Sapota Fruits

Sapota is an important climacteric fruit with limited shelf life. A special system must be employed to extend the shelf life of sapota fruits. In the present study, polyvinyl alcohol (PVA) and montmorillonite clay (MMt)-based bio-nanocomposite films (BNFs) were integrated at various concentrations (2%, 4%, 6%, and 8%) into cellulose nanocrystals (CNCs), produced from garlic peels (GPs). The BNF loaded with 8% CNC has a better crystallinity index and mechanical properties than the other concentrations of CNC. Therefore, the 8% CNC-incorporated BNF (BNF-8) was selected for further packaging studies. The combined effect of BNF-8 with ajwain essential oil (AO) and oregano essential oil (OO) vapors and BNF-8 with carbendazim (commercial fungicide-CARB) were investigated. In this study, the BNF-based packagings are categorized into five types, viz: BNF+8% CNC (BNF-8), BNF-8+AO, BNF-8+OO, BNF-8+CARB and the non-packaged fruits (control). The shelf-life duration, antioxidant activity, firmness, decay index, and sensory quality were evaluated in order to identify the effectiveness of packaging treatment on sapota fruits. BNF-8+CARB, BNF-8+AO, and BNF-8+OO packaging extended the shelf life of sapota fruits to up to 12 days and maintained the overall physiochemical parameters and sensory qualities of the fruits. Therefore, the BNF-8+AO and BNF-8+OO packaging materials are appropriate alternatives to commercial fungicides for the preservation of sapota during postharvest storage.

Development and characterization of active packaging based on chitosan/chitin nanofibers incorporated with scallion flower extract and its preservation in fresh-cut bananas

The aim of this study was to develop a novel active packaging using chitosan (CS) and esterified chitin nanofibers (CF) combined with different contents (1, 2 and 4 wt% on CS basis) of scallion flower extract (SFE) to protect banana samples. The addition of CF significantly improved the barrier and mechanical properties of the CS films (p < 0.05) due to hydrogen bonds and electrostatic interactions. Moreover, the addition of SFE not only improved the physical properties of the CS film but also improved the CS film biological activity. The oxygen barrier property and antibacterial ability of CF-4%SFE were approximately 5.3 and 1.9 times higher than those of the CS film, respectively. In addition, CF-4%SFE had strong DPPH radical scavenging activity (74.8 ± 2.3 %) and ABTS radical scavenging activity (84.06 ± 2.08 %). Fresh-cut bananas stored in CF-4%SFE showed less weight loss, starch loss, color and appearance change than those stored in traditional polyethylene film, which indicated that CF-4%SFE was much better at storing fresh-cut bananas than conventional plastic packaging. For these reasons, CF-SFE films have great potential as a candidate to replace traditional plastic packaging and extend the shelf life of packaged foods.

Preparation of biodegradable composite films based on carboxymethylated holocellulose from wheat straw

Holocellulose was extracted from wheat straw and catalytically transformed into carboxymethylated holocellulose (CMHCS) to prepare a biodegradable composite film. By changing the type and amount of catalyst, the carboxymethylation of the holocellulose was optimized with respect to the degree of substitution (DS). A high DS of 2.46 was achieved in the presence of a cocatalyst composed of polyethylene glycol and cetyltrimethylammonium bromide. The effect of DS on the properties of CMHCS-derived biodegradable composite films was further investigated. Compared to pristine holocellulose, the mechanical properties of the composite film were significantly improved and increased with increasing DS. The tensile strength, elongation at break, and Young's modulus increased from 6.58 MPa, 51.4 %, and 26.13 MPa for the unmodified holocellulose-based composite film to 14.81 MPa, 89.36 %, and 81.73 MPa for the film derived from the CMHCS with a DS of 2.46. The biodegradability of the composite film was assessed under soil burial biodisintegration conditions and reached 71.5 % degradation after 45 d. Additionally, a possible degradation process for the composite film was proposed. The results indicated that the CMHCS-derived composite film has good comprehensive performance, and CMHCS is expected to be applied in the field of biodegradable composite materials.

Development of chitosan/rice protein hydrolysates/ZnO nanoparticles films reinforced with cellulose nanocrystals

In the present work, the composite films were obtained by the solution casting method from chitosan and rice protein hydrolysates, reinforced with cellulose nanocrystals (CNC) of different contents (0 %, 3 %, 6 % and 9 %). The influence of different CNC loadings on the mechanical, barrier and thermal properties was discussed. SEM showed the formation of intramolecular interactions between the CNC and film matrices, leading to more compact and homogeneous films. These interactions had a positive influence on the mechanical strength properties, which was reflected in higher breaking force of 4.27 MPa. The elongation dwindled from 132.42 % to 79.37 % with increasing CNC levels. The linkages formed between the CNC and film matrices reduced the water affinity, leading to a reduction in their moisture content, water solubility and water vapor transmission. Thermal stability of the composite films was also improved in the presence of CNC, by increasing maximum degradation temperature from 311.21 to 325.67 °C with increasing CNC contents. The strongest DPPH inhibition of the film was 45.42 %. The composite films exhibited the highest inhibition zone diameter against E. coli (12.05 mm) and S. aureus (12.48 mm), and the hybrid of CNC and ZnO nanoparticles exhibited stronger antibacterial activity than their single existent forms. The present work shows the possibility of obtaining CNC-reinforced films with improved mechanical, thermal and barrier properties.

Preparation and characterization of functionalized chitosan/polyvinyl alcohol composite films incorporated with cinnamon essential oil as an active packaging material

In this study, amphiphilic chitosan (NPCS-CA) was synthesized by grafting quaternary phosphonium salt and cholic acid onto the chain of chitosan, aiming to develop an active edible film based on NPCS-CA and polyvinyl alcohol (PVA) incorporated with cinnamon essential oil (CEO) by the casting method. The chemical structure of the chitosan derivative was characterized by FT-IR, ¹H NMR and XRD. Through the characterization of FT-IR, TGA, mechanical and barrier properties of the composite films, the optimal proportion of NPCS-CA/PVA was determined as 5/5. And, the tensile strength and elongation at break of the NPCS-CA/PVA (5/5) film with 0.4 % CEO were 20.32 MPa and 65.73 %, respectively. The results revealed that the NPCS-CA/PVA-CEO composite films exhibited an excellent ultraviolet barrier property at 200-300 nm and significantly reduced oxygen permeability, carbon dioxide permeability and water vapor permeability. Furthermore, the antibacterial property of film-forming solutions against E. coli, S. aureus, and C. lagenarium was distinctly improved with the increase of NPCS-CA/PVA proportion. And, the multifunctional films effectively extended the shelf-life of mangoes at 25 °C based on the characterization of surface changes and quality indexes. The NPCS-CA/PVA-CEO films could be developed as biocomposite food packaging material.

Dragon Fruit Peel Extract Enriched-Biocomposite Wrapping Film: Characterization and Application on Coconut Milk Candy

Bio-based film is an eco-friendly alternative to petroleum-based packaging film. The effects of biocomposite wrapping film enhanced with dragon fruit peel extract (0, 2% w/v, respectively) and currently used commercial packaging film (polypropylene; PP) on coconut milk caramels during storage (30 °C, 75% RH, nine days) were studied. Both 0% and 2% DPE-enriched biocomposite films were thicker and had higher water vapor permeability and solubility than the PP film but poorer mechanical characteristics. In addition, the 2% film possessed antioxidants and antioxidant ability. A FESEM micrograph revealed the rough surface and porous path of the biocomposite films. Over the storage time, the moisture content, water activity, and springiness of the coconut milk caramel candy wrapped in the PP and all DPE-enriched biocomposite films were not significantly altered. However, the lipid oxidation as the thiobarbituric acid reactive substance (TBARS) and hardness of all coconut caramels were significantly (p < 0.05) increased during storage. Furthermore, the hardness of coconut candy covered in the control (0% DPE) biocomposite film was more pronounced on day nine of storage. However, the changes in quality characteristics of the coconut candy wrapped in each film type need to be better established. The investigating factors influencing the quality deterioration of coconut milk candy should be further identified to mitigate their effects and extend the shelf-life of the coconut candy.

Evaluation of Pretreatments and Extraction Conditions on the Antifungal and Antioxidant Effects of Garlic (Allium sativum) Peel Extracts

This study aimed to evaluate the effect of pretreatments and extraction conditions on the antioxidant and antifungal characteristics of garlic peel extracts. The effect of pretreatments (fermentation and steam cooking) on the yield, antifungal (Colletotrichum gloeosporioides and Botrytis cinerea), and antioxidant (total phenolic compounds, total flavonoids, and antioxidant capacity) properties of garlic peel extracts were evaluated. A selected pretreatment was applied to evaluate the extraction conditions (solvent, solvent concentration, temperature, and time) on the antifungal activity of garlic peel extracts. At last, garlic peel extracts obtained under specific conditions was applied to papaya and strawberry fruits as preventive and curative treatments against Colletotrichum gloeosporioides and Botrytis cinerea, respectively. Steam cooking pretreatment significantly increased the antifungal and antioxidant capacities of garlic peel extracts compared to the fermentation process. Garlic peel extracts obtained with methanol (60%) for 18 h (25 °C) showed the highest antifungal activity against both microorganisms assessed (57.57% and 75.76% for B. cinerea and C. gloeosporioides, respectively,) on in vitro assays. Moreover, in vivo results indicated that preventive treatment significantly reduced rot disease in papaya (88.95%) and strawberry (54.13%) fruits. Although more studies about the antifungal mechanisms of garlic peel extracts are needed, these results indicated that garlic peel extracts could be used as an antifungal agent.

Investigation of the effects of extraction temperature and time on bioactive compounds content from garlic (Allium sativum L.) husk

Garlic (Allium sativum L.) has been used as a functional food and medicine in traditional prescriptions for centuries. The extract of garlic husks contains phytonutrients and antioxidant capacity, which can be applied in the food, nutraceutical, cosmetics, and pharmaceutical industries. However, garlic husks, a by-product of the food industry, are considered agricultural wastes. Hence, this research aims at evaluating the content of several compounds in the extract of garlic husks and determining the appropriate temperature and time for the extraction processing of bioactive compounds from garlic husks. In this research, garlic husk powder was extracted at different temperatures from 40 to 80oC during time durations of 30–120 min. This study found that the optimum temperature was from 60 to 70oC and the time duration was from 60 to 90 min for the extraction process. The optimal content of total polyphenols content of 8.93 ± 0.252 mg gallic acid equivalent/g, total flavonoids content of 0.028 ± 0.002 (mg quercetin equivalent/g), total thiosulfinates content of 9.73 ± 0.071 (μmol/g), and total anthocyanins content of 0.0047 ± 0.0001 (mg/g) of dried garlic husk. Based on the finding, the study suggests that garlic husk should be utilized as a potential source of natural antioxidants in garlic extract, a food supplement, that contains antioxidants to support the cardiovascular and immune systems+ and odorless garlic products.

Emerging Food Packaging Applications of Cellulose Nanocomposites: A Review

Cellulose is the most abundant biopolymer on Earth, which is synthesized by plants, bacteria, and animals, with source-dependent properties. Cellulose containing β-1,4-linked D-glucoses further assembles into hierarchical structures in microfibrils, which can be processed to nanocellulose with length or width in the nanoscale after a variety of pretreatments including enzymatic hydrolysis, TEMPO-oxidation, and carboxymethylation. Nanocellulose can be mainly categorized into cellulose nanocrystal (CNC) produced by acid hydrolysis, cellulose nanofibrils (CNF) prepared by refining, homogenization, microfluidization, sonification, ball milling, and the aqueous counter collision (ACC) method, and bacterial cellulose (BC) biosynthesized by the Acetobacter species. Due to nontoxicity, good biodegradability and biocompatibility, high aspect ratio, low thermal expansion coefficient, excellent mechanical strength, and unique optical properties, nanocellulose is utilized to develop various cellulose nanocomposites through solution casting, Layer-by-Layer (LBL) assembly, extrusion, coating, gel-forming, spray drying, electrostatic spinning, adsorption, nanoemulsion, and other techniques, and has been widely used as food packaging material with excellent barrier and mechanical properties, antibacterial activity, and stimuli-responsive performance to improve the food quality and shelf life. Under the driving force of the increasing green food packaging market, nanocellulose production has gradually developed from lab-scale to pilot- or even industrial-scale, mainly in Europe, Africa, and Asia, though developing cost-effective preparation techniques and precisely tuning the physicochemical properties are key to the commercialization. We expect this review to summarise the recent literature in the nanocellulose-based food packaging field and provide the readers with the state-of-the-art of this research area.