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The recover of the used Ag-graphene-TiO2 composite extracted from the polylactic acid (PLA) film and its characterization in comparison with the newly prepared composite was the aim of this study. The proposed recovery procedure will reduce the amount of inorganic nanostructured material released into the environment as used food packaging. Morpho-structural, environmental and photocatalytical characteristics of Ag-graphene-TiO2 composite recovered from an used PLA-based film in comparison with those of the new prepared composite are reported. The recovered Ag-graphene-TiO2 composite displayed color, consistence, appearance, homogeneity and dispersion of nano-Ag similar with the new prepared compound. The FTIR spectroscopy showed the presence of Ti–O–C bonds suggesting the cross-linking between TiO2 and graphene both in new and recovered composite. The gap energy (Eg) of the recovered composite is 1.4 times and 2.3 times lower than that of new composite and TiO2, respectively. The anatase's content decreased by 70% during the recovering, while that of rutile rised with the same magnitude. The photocatalytic activity of the recovered composite decreased only by 30% in comparison with the new composite. Additionally, the Life-Cycle Analysis (LCA) showed that the recovering procedure had a considerably lower environmental impact than the preparation of the new composite in terms of human health, ecosystem quality, climate change and resources. In conclusion, the recovering of the nanostructed composites from the active PLA-based films should be promising way to imporve the waste management. [ABSTRACT FROM AUTHOR]

The increase in the polymer-based materials needs has induced along the waste accumulation, thus argued higher interest in recycling. The study aims to assess the structural, morphological, mechanical resistance, physical–chemical and biochemical characteristics, as well as the preservative role during the curd cheese storage of a recycled polylactic acid (PLA)-based film modified with Ag-graphene-TiO2 nanostructured composite, obtained by recovering the composite from the used film, followed by its incorporation in new PLA. The breaking load of the recycled film was 24% lower than that of the new film and 10% higher than of the neat PLA. Differential scanning calorimetry (DSC) showed changes of the recycled PLA's surface tension and crystallization degree in a greater extent than in the newly prepared film, revealing better incorporation of the recovered composite into the PLA matrix. Fourier transformed infrared spectroscopy showed the formation of C–O–Ti bridges between composite and PLA both in new and recycled film. Oxygen transmission rate (OTR) of the new and recycled film decreased by 33% and 45%, respectively, in comparison with reference PLA. The curd cheese was successfully stored in the recycled packaging; the organoleptic characteristics of cheese wrapped in recycled film were superior in comparison with the new film. The variation of fat and protein contents and mass loss was the lowest when the recycled film was used as packaging material. The study successfully showed the possibility to recover and recycle the used PLA-based films modified with inorganic nanocomposites. [ABSTRACT FROM AUTHOR]

This research studies the influence of the marinade composition and of the vacuum heat treatment (Sous Vide procedure) on the physical-chemical properties of six types of deer meat. Three types of marinades made up of ingredients with different properties have been prepared. The packets of marinated meat vacuumed and sealed were subjected to the Sous Vide technique (thermal treatment at 60 °C, for 4 hours). The characterization was performed both on crude and cooked marinated samples and consisted of colorimetric and textural analysis, determination of hardness, elasticity, pH and mass loss. The results showed that the M3 marinade containing pickled red beet juice, anise, cinnamon, cloves, ground ginger, junibahar, honey, colored pepper, chilli powder and salt, showed the more efficient improvement of the deer meat, best retained its elasticity and induced the lowest color change. Thus, the M3 marinade is a promising solution for deer meat in order to obtain an attractive culinary preparate. [ABSTRACT FROM AUTHOR]

The purpose is to develop polyvinyl alcohol (PVA)-based formulations with water vapor permeability (WVP) comparable to polyethylene (PE). Seventeen samples were created by modifying PVA with beeswax, citric acid and surfactant, varying heat treatment conditions. Characterization involved optical and electron microscopy, elemental analysis, WVP and biodegradability assessments. Sample B9, with 3% citric acid, heat-treated at 125°C for 30 minutes, exhibited the lowest WVP (0.673 x 10-10 g/s m Pa). B9 was tested as a bread packaging material, displaying similar crust hardness behavior to PE after 1 day and 26.4% higher hardness than PVA after 4 days. B9 matched PE in dry matter preservation after 2 days. Thus, the modification with citric acid, bee wax and by heat treatment, led to an 88% reduction in PVA's water vapor permeability compared to unmodified PVA. The findings suggest B9's potential as an effective alternative packaging material with improved barrier properties and bread preservation capabilities. [ABSTRACT FROM AUTHOR]

Abstract: Three active cellulose-based papers coated in chitosan (P-CH), chitosan-TiO2 (P-CH-TiO2) and chitosan-Ag/TiO2 (P-CH-Ag/TiO2), respectively were real-time aged for 6 months at 4°C, 55% relative humidity, 15 h light/9 h dark cycle and characterized in relation to plain paper (P). The reduction in the chitosan cristallinity, N-deacetylation of chitosan, degradation of cellulosic fibers and loss in the active agents (proven by SEM, FTIR, EDX techniques and physical-chemical-microbial measurements) occurred during storage explains the deterioration of the barrier and antimicrobial properties of the active papers and subsequently the decrease in their preservation efficiency. Experimental results indicate that after storage for 6 months of the clarified butter the most effective package was P-CH-Ag/TiO2 for which the lowest levels of PV (2.72 mEq O2/kg), yeasts and molds (5.8 CFU/g) and E. coli (6.12 CFU/g) counts were measured. By mathematical modeling of the evolution of the PV, E. coli, yeasts and molds experimental profiles the shelf-life of the clarified butter packed in P, P-CH, P-CH-TiO2 and P-CH-Ag/TiO2 was assessed in respect to their admitted limits to 1.6, 2, 4 and 9.3 months, respectively. At the end of storage the appearance of P-CH-Ag/TiO2 package was clean, without greasy spots, as opposed to that of P, P-CH and P-CH-TiO2, which proves its self-cleaning property.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Cotton fabric decorated with TiO2 synthesized by sol‐gel approach was investigated as a self‐cleaning material depending on the TiO2 loading (1.5 wt% in the case of single layered fabric and 3 wt% in the case of double layered). The materials were investigated by SEM, EDX, XRD, FTIR, and photoactivity. The self‐cleaning property was established by determining the amount of the coated dust, the elemental composition, the carbon content, the opacity, and the water contact angle. The self‐cleaning property of the impregnated fabric was accentuated by TiO2 loading. The dust deposited on the single layer fabric stored inside was 3.8 wt% lower than on the nonimpregnated fabric and that deposited on double layer fabric, respectively, was reduced by 9.1 wt%. The decrease in the deposited dust was more accentuated for the samples stored outside (4.2 wt% for the single layer fabric and 16 wt% for the double layer fabric, as compared with the nonimpregnated textile). Schematic mechanism of self‐cleaning [ABSTRACT FROM AUTHOR]

Abstract: Three active cellulose-based papers coated with chitosan (P-CH), chitosan-TiO2 nanocomposite (P-CH-TiO2) and chitosan-Ag/TiO2 nanocomposite (P-CH-Ag/TiO2), respectively, were subjected to real-time ageing for 6 months at 25 °C and 45% re humidity and characterized from a physical-chemical-antimicrobial perspective in relation to plain paper (P). Scanning electron microscopy pictures indicate a smooth morphology in the active papers, while the structure of P is rough with large pores. The fresh papers containing nanocomposites displayed enhanced barrier properties against water vapor, air and grease. The photocatalytic action of TiO2 during ageing results in the deacetylation of the chitosan layer and the degradation of cellulosic fibers with a reduction of barrier properties. Fresh P-CH-Ag/TiO2 displayed the highest value of inhibition index against yeasts and molds (95.65%), its value decreasing to 79.25% after 6-month storage. Walnut kernels were stored for 6 months at 25 °C and 45% RH in packages made of investigated papers and analyzed. It was found that P-CH-Ag/TiO2 is the most effective in the prolongation of the shelf-life of kernels. They are assessed to be safe in terms of peroxide value and yeasts and molds count for 11.6 and 15.1 months when stored in P-CH-Ag/TiO2 filled with 25 and 50 g kernels, respectively, as compared to 1.8 and 3.4 months, respectively when they are stored in P. The appearance of packages containing nanocomposites was clean without grease spots in opposition with that of P and P-CH and proves the self-cleaning property of P-CH-TiO2 and P-CH-Ag/TiO2. Cluster diagrams indicate a strong correlation between the quality and safety of kernels and properties of paper sheets in a paper type-depending manner.Graphical abstract: [ABSTRACT FROM AUTHOR]

This research was undertaken to establish the preservative role of lactic acid (LA) and salicylic acid (SA) included in a gelatin-glycerol film over the harvested plums. The results showed that highest catalase activity was achieved for the plums modified with LA 0.2% wt and with SA 0.00375 M, after 12 days of storage. The most reduced variation of the physical, chemical, and enzymatic parameters was noticed in the plums coated with LA 0.2% wt. Statistical processing showed that the variation of all physical-chemical parameters, excepting catalase is significant. Variation of catalase is significant only in the case of the plums modified with LA 3% wt and of reference plums. Thus, the coating of the harvested plums with a low amount of LA (≤0.2% wt) can be considered as preservation method during storage for 12 days. Practical applications Lactic acid (LA) and salicylic acid (SA) were coated on the harvested plums and their role as preservative during the fruit storage was established. The results showed that coating the harvested plums with a gelatin-glycerol film modified with LA at low concentration (≤0.2% wt) is an efficient method for preservation at room temperature for 12 days, taking in consideration that the commercial shelf life of harvested plums is 2-6 weeks, at 0 °C. [ABSTRACT FROM AUTHOR]

Removal of lead ions from aqueous solutions, in the presence and in absence of commercial TiO2, under UV-light was studied. The influence of catalyst mass, concentration of Pb(II) ions and of citric acid in the starting solution as well as the impact of illumination conditions on the removal rate were also investigated. The results were fitted on the pseudo-first order, pseudo-second order and Elovich kinetic models, Weber-Morris intraparticle and liquid film diffusion models, in order to establish the photoreduction mechanism. The Pb removal rate increased in time by a combined linear-exponential mechanism. The catalyst had a positive influence on the removal rate at the start of the photoreduction. At a low concentration of Pb(II) ions (20 mg/L), the amount of photoreduced Pb(II) ions was proportional to the concentration of the citric acid solution, but at high concentrations (240 mg/L), the correlation was inversely proportional. The rate limiting steps in the removal of lead were both the photoreduction on the TiO2 surface and the diffusion through the film surrounding the catalyst particle. The lead removal was significantly influenced by the mobility and by the concentration of the species in solution. [ABSTRACT FROM AUTHOR]

Green bell peppers fruits, stored for 1 month at 8oC and 45±5% relative humidity in Far-Red light (FRL) and darkness respectively, were investigated in terms of physical, chemical and microbiological parameters. The exposure to FRL slows down the water loss from fruits by stimulating the surface wax biosynthesis into a higher specific amount and hydrophobic nature and reducing the apertures, diameters of the pericarp cells, intercellular walls and dermal layer thicknesses. The higher level of catalase enzyme in the FRL-exposed fruits resulted in lower chilling injury index in comparison with the one in fruits exposed to darkness. FRL has favorable effect on chlorophyll and carotenoids accumulation rates. The multiplication of yeasts and molds on the surface of FRL-exposed bell peppers was significantly delayed as compared to the multiplication on the surface of the darkness-exposed bell peppers. [ABSTRACT FROM AUTHOR]