Active coatings of thermoplastic starch and chitosan with alpha-tocopherol/bentonite for special green coffee beans

Release kinetics of eugenol and α-tocopherol from carrageenan films for meat preservation

This paper introduces a novel active carrageenan film designed for meat preservation, featuring the release of antioxidants eugenol (Eu) and α-tocopherol (Tp). The film is composed of semi-refined carrageenan, plasticized with 0.9 % glycerol, and reinforced with 10 % cellulose nanofibers derived from waste biomass. Lipid oxidation was measured through TBARS and percent metmyoglobin to evaluate the film's effectiveness in extending the shelf-life and maintaining the quality of meat. The film containing 0.4 % Tp demonstrates superior mechanical properties and thermal stability, achieving a tensile strength of 66.79 MPa and an elongation at break of 46.54 %. Notably, it exhibits a significant antioxidant release rate over 25 days, with TBARS and percent metmyoglobin values of 0.652 and 35.98 %, respectively. These results suggest that this biodegradable packaging solution not only prolongs meat shelf-life but also aligns with sustainable practices in food preservation. The release profiles of Eu and Tp follow a first-order kinetic model, indicating a controlled and sustained release mechanism. Overall, these findings highlight the potential of active films in enhancing food packaging solutions while promoting eco-friendliness.

Natural biopolymers in edible coatings: Applications in food preservation

Edible coatings are revolutionizing food preservation by offering a sustainable and effective solution to key industry challenges. Made from natural biopolymers such as proteins, polysaccharides, and lipids, these coatings form a thin, edible layer on food surfaces. This barrier reduces moisture loss, protects against oxidative damage, and limits microbial growth, thereby extending shelf life while preserving food quality. Enhanced with natural additives like essential oils and antioxidants, these coatings offer antimicrobial benefits and contribute to health. Applications span from fresh produce, where they control respiration and moisture, to meat, dairy, and bakery products, maintaining sensory and nutritional properties. Innovations in coating technologies-such as composite materials, nano-emulsions, and bio-nanocomposites-are improving their mechanical strength, barrier properties, and compatibility with other preservation methods like modified atmosphere packaging. Although challenges remain in cost, consumer acceptance, and regulation, edible coatings represent a significant stride towards sustainable food systems and reduced dependence on synthetic packaging.

Evaluation of the Food Barrier and Mechanical Properties of Carrageenan-Starch Composite Films

Single use plastics are a leading source of microplastics that have been detected along the food chain. This study evaluated the potential of starch (ST) and carrageenan (CRG) in packaging film formulation. CRG isolated from the seaweed (SW) Eucheuma denticulatam was blended with starch and cast to obtain films whose moisture content (MC), total soluble matter (TSM), degree of solubility (DS), water vapor permeability (WVP), opacity (O), contact angles (CA), moisture absorption (MA), and percent elongation (PE) were evaluated. The films' morphology, crystallinity, opacity, thermal profile, and functional groups were then studied by scanning electron microscopy, powder diffraction, UV-Vis, thermal gravimetry, and infrared spectroscopy. From the results obtained, the SWF films exhibited a higher MC, DS, and TSM than CRG and CRG-ST films but lower DC values. The PE of CRG films was lower than that of SWF (30%) though incorporation of ST increased the PE of CRG-ST. However, SWF films had WVP of 2.25 × 10-7 gs-1m-1Pa-1, compared to 3.65 × 10-7 gs-1m-1Pa-1 of CRG, 2.73 × 10-7 gs-1m-1Pa-1 of CRG-ST and a moisture absorption of 29.29 ± 3.5 as compared to 17.29 ± 0.87 of CRG and 23.80% ± 4.12% of CRG-ST. The opacities were found to be 41.02, 79.89, and 42.23 for SWF, CRG, CRG-ST while the contact angles were found to be 72.86, 80.93, 65.57 for SWF, CRG, and CRG-ST, respectively. Moreover, the films were impermeable to vegetable oil, had carbohydrate functional groups, good thermal stabilities, and trace micronutrients. In conclusion, this study formulated packaging films with enhanced food barrier and mechanical properties that can potentially replace single use packaging films.

Gelatin/polyvinyl alcohol films loaded with doubly stabilized clove essential oil chitosomes: Preparation, characterization, and application in packing marinated steaks

In this study, a promising active food-packaging film of Gelatin/polyvinyl alcohol (GEL/PVA) integrated with doubly stabilized clove essential oil chitosome nanoparticles (CNP) was developed to maintain the freshness of marinated steaks. Results from the XRD and SEM experiments indicated excellent compatibility between the CNP and GEL/PVA matrix. Additionally, CNP was found to introduce more free hydroxyl groups, enhance the water retention and surface wettability of the CNP-GEL/PVA (C-G/P) film, and significantly reduce the swelling index from 963.78% to 495.11% (p < 0.05). Notably, the highest tensile strength and elongation at break (53.745 MPa and 46.536%, respectively) were achieved with the addition of 30% (v/v, based on the volume of gelatin) CNP; UVC was fully absorbed with 40% CNP; and films containing 60% CNP showed optimal inhibition of both Staphylococcus aureus and Escherichia coil, extending the shelf life of marinated steak from 3 to 7 days.

Cassava Starch/Carboxymethyl Cellulose Edible Coating Added of Tocopherol: A Strategy to Preserve the Oxidative Stability of Brazil Nuts

The aim was to apply a cassava starch/carboxymethyl cellulose blend-based edible coating added to a tocopherol mix to Brazil nuts and evaluate oxidative levels during storage. The edible coatings were prepared from a cassava starch/carboxymethyl cellulose blend and identified as control B (no soy lecithin and no tocopherol mix), L (with soy lecithin and no tocopherol mix), and LT and LT2 (with soy lecithin and tocopherol mix). In the forming solutions of the coatings, stability, viscosity, pH, and color were analyzed. The Brazil nuts were immersed in the solutions for 30 s, dried at 45 °C, and placed in an incubator at 25 °C. At 1, 7, 15, 30, 45, 60, 90, and 120 days of storage, mass loss, the browning index, conjugated dienes and trienes, the oxidative state by official methods, and the accelerated oxidation index were evaluated. The blend-forming solutions B, L, LT, and LT2 showed non-Newtonian and pseudoplastic behavior, excellent resistance to flow, and stability. The diene, triene, iodine value, peroxide value, p-anisidine value, and total oxidation indices showed that the application of the cassava starch/carboxymethyl cellulose blend-based edible coating added tocopherol mix, LT, and LT2 preserved the Brazil nuts up to 90 days of storage at 25 °C. PCA shows that all coatings applied to Brazil nuts promoted oil preservation in some evaluation periods, especially those added with a tocopherol mix. It is concluded that cassava starch/CMC added tocopherol mix edible coatings have a potential application as active packaging for foods, especially nuts.

Exploring the Potential of Seaweed Derivatives for the Development of Biodegradable Plastics: A Comparative Study

Biodegradable films made from biopolymer materials have the potential to replace conventional plastics, which can reduce waste disposal problems. This study aims to explore the potential of different seaweed derivate films consisting of 2% (w/w) of kappaphycus alverezi (KA), kappa carrageenan (KC), refined carrageenan (RC) and semi-refined carrageenan (SRC) as bio-based materials with 0.9% (w/w) glycerol (G), and reinforced with different concentrations of cellulose nanofibers (CNFs) derived from palm waste. A characterization of the glycerol-plasticized seaweed derivatives containing 0, 5, 10, and 15% (v/w) cellulose nanofiber is carried out. The CNFs were studied based on their mechanical, physical and thermal properties including mechanical properties, thickness, moisture content, opacity, water solubility, water vapor permeability and thermal stability. The hydrogen bonding was determined using the DFT calculation generated by Gauss view software version 9.6. The KA + G + 10%CNF film exhibited a surface with slight cracks, roughness, and larger lumps and dents, resulting in inferior mechanical properties (18.50 Mpa), making it unsuitable for biofilm production. The KC + G + 10%CNF film exhibited mechanical properties 24.97 Mpa and water vapor permeability of 1.42311 × 10^-11 g s^-1 m^-1 Pa^-1. The RC/G/10%CNF film displayed the highest TS (48.23 MPa) and water vapor permeability (1.4168 × 10^-11 g s^-1 m^-1 Pa^-1), but it also had higher solubility in water (66%). In contrast, the SRC + G + 10%CNF film demonstrated excellent mechanical properties (45.98 MPa), low water solubility (42.59%), low water vapor permeability (1.3719 × 10^-11 g s^-1 m^-1 Pa^-1), and a high decomposition temperature (250.62 °C) compared to KA, KC and RC. These attributes develop films suitable for various applications, including food packaging with enhanced properties and stability.

Recent advances in extraction, modification, and application of chitosan in packaging industry

Current environmental concerns fostered a strong interest in extracting polymers from renewable feedstocks. Chitosan, a second most abundant polysaccharide after cellulose, may prove to be a promising green material owing to its renewability, inherent biodegradablity, natural availability, non-toxicity, and ease of modification. This review is intended to comprehensively overview the recent developments on the isolation of chitosan from chitin, its modification and applications as a reinforcing candidate for food packaging materials, emphasizing the scientific underpinnings arising from its physicochemical properties, antimicrobial, antioxidant, and antifungal activities. We review various chitosan-reinforced composites reported in the literature and comprehensively present intriguing mechanical and other functional properties. We highlight the contribution of these mechanically robust and responsive materials to extend the shelf-life and maintain the qualities of a wide range of food commodities. Finally, we assess critical challenges and highlight future opportunities towards understanding the versatile applications of chitosan nanocomposites.

Effect of the incorporation of lignin microparticles on the properties of the thermoplastic starch/pectin blend obtained by extrusion

The present study aimed to produce thermoplastic starch films with different concentrations of thermoplastic pectin and the addition of 4% lignin microparticles as a reinforcing and active agent. The pectin improved the modulus of elasticity, and decreased the elongation at break. In addition, it improved the UV light protection to 100% at 320 nm and 95.9% at 400 nm. The incorporation of lignin microparticles improved the thermal stability of the blends made with 25% and 50% thermoplastic pectin when compared to the pectin-free blends. The blend with 25% thermoplastic pectin led to an increase of 75.8% and 34% in elongation at break and deformation of the films, respectively. This blend also improved the UV light protection to 100% due to its dark brown color. Regarding the permeability properties, the films with 25% and 50% thermoplastic pectin showed lower oxygen permeability (48% and 65%) and an increase in the antioxidant activities from 2.7% to 71.08% and 4.1% to 79.28%, respectively. Thus, the polymer blend with 25% thermoplastic pectin with the incorporation of lignin microparticles proved to be a good alternative for use in foods sensitive to the effects of oxygen and UV light.