Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Materials (Basel) ; 17(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39274567

RESUMO

The characterization and modeling of the out-of-plane behavior of fiber-based materials is essential for understanding their mechanical properties and improving their performance in various applications, especially in the forming process. Despite this, research on paper and paperboard has mainly focused on its in-plane behavior rather than its out-of-plane behavior. However, for accurate material characterization and modeling, it is critical to consider the out-of-plane behavior. In particular, delamination occurs during forming processes such as creasing, folding, and deep drawing. In this study, three material models for paperboard are presented: a single all-material continuum model and two composite models using different cohesion methods. The two composite models decouple in-plane and out-of-plane behavior and consist of continuum models describing the behavior of individual layers and cohesive interface models connecting the layers. Material characterization experiments are performed to derive the model parameters and verify the models. The models are validated using three-point bending and bulge tests and show good agreement. A case study is also conducted on the application of the three models in the simulation of a deep drawing process with respect to wrinkle formation. By comparing the simulation results of wrinkle formation in the deep drawing process, the composite models, especially the cohesive interface composite model, show greater accuracy in replicating the experimental results, indicating that a single continuum model can also be used to represent wrinkles.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39102379

RESUMO

Food contact paperboard poses a potential risk of food contamination due to the possible release of chemicals (intentionally added or not), particularly in recycled paperboard. Water extractions were performed, according to wet food procedures, of paperboard samples collected from a manufacturer at the beginning and the end of a recycling production chain. Chemical analysis and hormonal activities in vitro of water extracts were studied. ICP-MS analysis confirmed the presence of 15 trace elements with lower concentrations after the recycling process, with the exception of chlorine. The chromatographic analyses demonstrated that the identified substances in the starting paperboard, before the recycling process, were approximately twice as high as in the end paperboard, after the recycling process. These substances included also natural wood products, chemical additives, and undesirable substances such as phthalates. Two major products (3,5-di-tert-butylphenol and methyl-2-pyrrolidone) were found in the starting and the end paperboard extracts, respectively. Two common substances were identified in both extracts: 2,4-di-tert-buthylphenol and dehydroabietic acid. Evaluation of potential endocrine disruption showed that the starting paperboard extract exhibited oestrogenic and antiandrogenic effects, while these effects nearly disappeared in the end paperboard extract. These results confirmed that the recycling process was effective in removing most of the contaminant substances.


Assuntos
Contaminação de Alimentos , Papel , Reciclagem , Contaminação de Alimentos/análise , Animais , Embalagem de Alimentos , Disruptores Endócrinos/análise , Disruptores Endócrinos/química , Humanos
3.
Environ Pollut ; 357: 124425, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38914196

RESUMO

This study analyzed pollutant emissions from laser cutters used in modeling in a laboratory, which can have harmful effects on indoor air quality and health. Four conditions were tested: material thickness, laser cutter strength, minimum strength per thickness, and air purifier level. Four pollutants were analyzed: PM2.5, HCHO, VOCs, and CO2. The study found that the emissions of PM2.5, HCHO, and VOCs increased with paperboard thickness, while CO2 emissions were not significant. PM2.5 was more affected by laser cutting strength, while HCHO and VOCs were more affected by paperboard thickness. Additionally, we analyzed the PM2.5 emission rates based on the thickness of the paperboard and the laser cutting strength. Therefore, emission rates based on thickness and laser cutting strength ranged from 7275 to 18,783 µg/min. The air purifier significantly reduced PM2.5 but not HCHO and VOCs. To reduce these gaseous pollutants, combining mechanical ventilation or using an air purifier with a filter that adsorbs HCHO and VOCs is effective. This study highlights the importance of considering laser cutters as a potential source of indoor air pollutants and implementing measures to mitigate their harmful effects.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Monitoramento Ambiental , Lasers , Material Particulado , Compostos Orgânicos Voláteis , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Material Particulado/análise , Compostos Orgânicos Voláteis/análise , Dióxido de Carbono/análise
4.
Materials (Basel) ; 17(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38399129

RESUMO

The article presents continued considerations presented in a prior publication on the development of a model for calculating the bending stiffness BS of cellular honeycomb paperboards, applying the strength properties of paper raw materials used for the production of paperboard and the geometric parameters of cellular board. The results of BS calculations obtained by using the analytical model presented in the prior publication were significantly overestimated in relation to the value obtained by measurements. The calculation error in relation to the measurement value for the tested group of paperboards in the case of bending stiffness in the machine direction MD was within the range from 23% to 116%, and the average error was 65%, while in the cross direction CD, it was within the range from 2% to 54%, and the average error was 31%. The calculation model proposed in this work based on the physical properties of cellular paperboard reduces the error values for bending stiffness in both the machine and cross directions. The value of the average error for both main directions in the paperboard plane was 10%. The method enables more accurate determination of BS in the machine direction MD and in the cross direction CD at the paperboard design stage. In order to validate the proposed analytical model, the calculation results were compared with the results of BS laboratory measurements performed using the four-point bending method and, in order to expand the group of tested paperboards, with the measurement results presented in the prior article for cardboards with different raw material composition and different geometric parameters.

5.
Artigo em Inglês | MEDLINE | ID: mdl-37831931

RESUMO

The objective was to establish a robust and reliable approach for the characterisation of volatile organic compounds (VOCs) present in food contact paperboard. This was achieved through the utilisation of headspace solid-phase microextraction in tandem with comprehensive two-dimensional (2D) gas chromatography (GC) and quadrupole time-of-flight mass spectrometry (HS-SPME-GC × GC-QTOF-MS). The experimental parameters were optimised, involving the use of a DVB/C-WR/PDMS fibre at a temperature of 80 °C for a duration of 30 min. A total of 344 VOCs comprising aldehydes, ketones, alcohols, ethers, esters, alkanes and aromatic compounds, were tentatively identified in the samples. Twelve compounds believed to be from biogenic sources had a high odour impact making them major contributors to potential taint from the paperboard samples. Significant attention should be devoted to five compounds namely, 2-methylnaphthalene, 2-pentyl-furan, furfural, 1-octen-3-one and 1-octen-3-ol due to their potential adverse impact on the organoleptic qualities of packaged food items and their potential toxicity.Abbreviations: C-WR: carbon wide range; DVB: divinylbenzene; GC-MS: gas chromatography - mass spectrometry; GCxGC-QTOF-MS: comprehensive two-dimensional gas chromatography coupled to quadrupole-time-of-flight - mass spectrometry; HS-SPME: headspace - solid phase microextraction; LOD: limit of detection; LOQ: limit of quantification; OAV: odor activity values; PDMS: polydimethylsiloxane; RI: retention index; TTC: threshold of toxicological concern; VOC: volatile organic compound.


Assuntos
Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Odorantes/análise , Microextração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Aldeídos/análise
6.
Materials (Basel) ; 16(19)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37834691

RESUMO

In the process of logistics, shock and vibration are the most important factors contributing to product damage. Assembling honeycomb paperboard and EPE is commonly used to provide cushioning and anti-vibration effects to materials. Therefore, it is necessary to study the vibration transmission properties of this kind of assembly in the anti-vibration process. The aim of this paper was to experimentally determine the vibration transmission properties of assemblies with honeycomb paperboard and expanded polyethylene (EPE). Through a sinusoidal sweep vibration test of this assembly, the vibration transmission characteristic curves of assemblies with honeycomb paperboard and EPE of different thicknesses were obtained and compared. Assuming the assembly and mass block as a single degree of freedom with a small damping linear system, the damping energy dissipation of the assembly and the resonance frequency were obtained. The vibration transmission property curves of the assembly can be divided into four regions. With an excitation acceleration of 0.5 g and a honeycomb paperboard with a thickness of 60 mm (F60), the vibration transmission rate and the resonance frequency-of the material dampened with EPE at a thickness of 60 mm (E60), and the assembly (F30/E30) with a 30 mm thick honeycomb paperboard and 30 mm thick EPE-increased by -2.5% and -17.5%, -86.9% and 79.3%, and -95.9% and -85.7%, respectively. Compared to the assembly with 20 mm thick honeycomb and 20 mm thick EPE (F20/E20), the vibration transmission rate, the resonance frequency, and the material damping and damping energy dissipation of F40/E20, F30/E30, and F20/E40 increased by 75.6%, 48.3%, and 66.1%; 1.2%, -21.5%, and -38.9%; 241.5%, 82.8%, and 13.3%; and 12.5%, 98.9%, and 106.8%, respectively. Compared to F60 and E60, the damping energy dissipation of F30/E30 increased by 2816.7% and 133.3%, respectively. The assembly of F30/E30 has the smallest vibration transmission rate and the most vibration energy dissipation among these assemblies. This means that the assembly of F30/E30 absorbs the most external vibration energy, while the acceleration that is transmitted to the internal product is minimal. Therefore, in the design of cushioning packaging, according to the characteristics and natural frequency of the internal products, an appropriate assembly can be selected, which should have a lower vibration transmission rate and more vibration energy dissipation, and should not resonate with the internal product. This will provide a theoretical basis for the design of cushioning packaging.

7.
Foods ; 12(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37509837

RESUMO

Paper is one of the packaging materials that presents a biodegradable character, being used in several areas; however, its barrier properties (gases and fat) and mechanics are reduced, which limits its application. Coating papers with synthetic polymers improve these properties, reducing their biodegradability and recyclability. The objective of this work was to develop and characterize coated paperboard, using the tape casting technique, with different ratios of film form agar-agar/chitosan (AA:CHI, 100:0, 50:50, and 0:100) and different numbers of coating layers (operating times for application of 14.25 min and 28.5 min for one and two layers, respectively). A significant reduction in water absorption capacity was found by applying a 0:100 coating (approximately 15%). Considering all coating formulations, the water vapor permeability reduced by 10 to 60% compared to uncoated paperboard, except for two layers coated with 0:100. The tensile index (independent of AA:CHI) was higher in the machine direction (22.59 to 24.99 MPa) than in the cross-section (11.87-13.01 MPa). Paperboard coated only with chitosan showed superior properties compared to the other formulation coatings evaluated.

8.
Materials (Basel) ; 16(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36984240

RESUMO

The finite element method is a widely used numerical method to analyze structures in virtual space. This method can be used in the packaging industry to determine the mechanical properties of corrugated boxes. This study aims to create and validate a numerical model to predict the compression force of corrugated cardboard boxes by considering the influence of different cutout configurations of sidewalls. The types of investigated boxes are the following: the width and height of the boxes are 300 mm in each case and the length dimension of the boxes varied from 200 mm to 600 mm with a 100 mm increment. The cutout rates were 0%, 4%, 16%, 36%, and 64% with respect to the total surface area of sidewalls of the boxes. For the finite element analysis, a homogenized linear elastic orthotropic material model with Hill plasticity was used. The results of linear regressions show very good estimations to the numerical and experimental box compression test (BCT) values in each tested box group. Therefore, the numerical model can give a good prediction for the BCT force values from 0% cutout to 64% cutout rates. The accuracy of the numerical model decreases a little when the cutout rates are high. Based on the results, this paper presents a numerical model that can be used in the packaging design to estimate the compression strength of corrugated cardboard boxes.

9.
Materials (Basel) ; 16(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36676213

RESUMO

In this study, the surface modification of thin ink films with added nanoparticles was used to improve the functional properties of ink applied on paperboard substrates. The surface modification was performed by additional exposure of the samples to xenon radiation. Anatase TiO2, rutile TiO2 and ZnO were added to the base ink. The effect of surface modification on the surface, structural, and mechanical properties of the printed ink films was determined by FTIR-ATR spectroscopy, calculating the surface free energy and adhesion parameters, performing the rub resistance test of the printed samples, and by measuring the resistance to bending. Color measurements on the ink films were performed in order to observe the optical properties of unmodified and modified samples. The results showed that surface modification significantly improved the adhesion properties of the thin ink films and the mechanical properties of the samples. The results obtained on uncoated and coated paperboard showed that the addition of rutile TiO2 and ZnO nanoparticles had the greatest effect on the rub resistance of the ink films. The results of the color analysis showed that the addition of nanoparticles did not change the optical properties of the modified ink films and that rutile TiO2 and ZnO nanoparticles improved the lightfastness of the applied ink films.

10.
Materials (Basel) ; 16(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36676335

RESUMO

Corrugated cardboard boxes are generally used in modern supply chains for the handling, storage, and distribution of numerous goods. These packages require suitable strength to maintain adequate protection within the package; however, the presence and configuration of any cutouts on the sidewalls significantly influence the packaging costs and secondary paperboard waste. This study aims to evaluate the performance of CCBs by considering the influence of different cutout configurations of sidewalls. The compression strength of various B-flute CCB dimensions (200 mm, 300 mm, 400 mm, 500 m, and 600 mm in length, with the same width and height of 300 mm), each for five cutout areas (0%, 4%, 16%, 36%, and 64%) were experimentally observed, and the results were compared with the McKee formula for estimation. The boxes with cutout areas of 0%, 4%, 16%, 36%, and 64% showed a linear decreasing tendency in compression force. A linear relationship was found between compression strength and an increase in cutout sizes. Packages with 0% and 4% cutouts did not show significant differences in compression strength (p < 0.05). Furthermore, this study shows a possible way to modify the McKee estimation for such boxes after obtaining empirical test data since the McKee formula works with a relatively high error rate on corrugated cardboard boxes with sidewall cutouts. Utilizing the numerical and experimental results, a favorable estimation map can be drawn up for packaging engineers to better manage material use and waste. The results of the study showed that the McKee formula does not appropriately estimate the box compression strength for various cutout sizes in itself.

11.
Artigo em Inglês | MEDLINE | ID: mdl-36696532

RESUMO

The migration of the biocides: 2-methyl-2H-isothiazol-3-one (MIT), 1,2-benzisothiazol-3(2H)-one (BIT) and 2-phenoxyethanol (PHE) from spiked paperboard into the simulants Tenax®, water and acetic acid (3%) has been studied and compared with that into the vegetables: red cabbage, lettuce and cauliflower. The migration of the biocides into the vegetables is significant and it shows the trend BIT > PHE > MIT, at both 4 °C and room temperature (RT), whatever tested foodstuff and with the highest value corresponding to BIT into cauliflower at RT (71%). Differences up to one order of magnitude between the biocides migration into Tenax® (<4.3%) and that into the vegetables indicate that Tenax® is not a suitable food simulant to mimic the selected vegetables in terms of the migration of the studied biocides. Water has been shown to be the most appropriate food simulant in the cases under study.


Assuntos
Ácido Acético , Verduras , Etilenoglicóis , Água , Embalagem de Alimentos , Contaminação de Alimentos
12.
Foods ; 11(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36553777

RESUMO

Synthetic polymer coatings impact the biodegradable behavior of cellulosic packaging material. The environmental consequences of food packaging disposal have increased consumer concern. The present study aimed to use natural polymer coatings incorporating palmitic acid and activated carbon applied to paperboard surfaces as a sustainable alternative to improve cellulosic packaging material's moisture and fat barrier properties, minimizing the environmental impact. The coating formulation was defined using a Factorial Experimental Design with independent variables: chitosan, palmitic acid, activated carbon concentrations, and the number of coating layers. The highest concentration of chitosan (2.0% w/w) filled the pores of the cellulosic paperboard network, supporting the compounds incorporated into the filmogenic matrix and improving the fat resistance. The water vapor permeability of the coated paperboard material (range: 101 ± 43 to 221 ± 13 g·d-1·m-2) was influenced by the hydrophobicity effect of palmitic acid, the non-polar characteristic of activated carbon, and the number of applied layers. The coating formulation selected was a chitosan concentration of 2.0% (w/w), a palmitic acid concentration of 1.8% (w/w), an activated carbon concentration of 1.2% (w/w), and an application of three layers. The coating provides the potential for a paperboard surface application, improving the cellulosic packaging material's fat and moisture barrier properties and maintaining biodegradability and recyclability.

13.
Patient Prefer Adherence ; 16: 179-188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35115766

RESUMO

BACKGROUND: Blister packs with paperboard backing, which is useful for displaying instructions and information, are the most popular type of packaging for osteoporosis drugs in Japan. However, the main users of drugs are the aged, who often find blister packs difficult to open or drop their pills during opening. In this study, we compared different types of blister packs in terms of usability and handling. METHODS: We conducted a subjective and objective study to compare commonly used blister packs with newly designed ones that have a jagged notch designed to hold a pill temporarily and a perforated line that enables the pack to be held easily in one hand. Regarding subjective data, packaging and sensory tests were performed. The participants in the sensory test were healthy older adults and patients with rheumatoid arthritis (RA). We also measured the pinch power of all participants. RESULTS: A comparison of several items, including opening status, prevention of pill dropping, and understanding of the instructions, using a numerical rating scale revealed no significant differences between ordinary (type A) and newly designed (type B) packaging. However, the scores for type B were the same or better than those for type A for every evaluation item. In addition, more than 85% of the participants reported preferring to use type B. More than 80% of the participants in both groups reported dropping pills using type A, which seemed to be related to their preference for type B. In the evaluation by the examiner (objective study), all participants could successfully remove their pills without dropping using type B, including those in the RA group who had difficulty handling packages. CONCLUSION: These findings suggest that the new type of blister pack assessed in this study (type B) is preferable among older and shows promise for a universal design.

14.
Materials (Basel) ; 16(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36614496

RESUMO

This article analyzes the influence of the initial deflection of the flat layers on the bending stiffness (BS) of honeycomb paperboards and presents two methods for its calculation. Both methods allow for the determination of BS in the main directions in the plane of the paperboard, i.e., the machine direction (MD) and the cross direction (CD). In addition, they have been verified by comparing the calculation results with the results of the BS measurements. The first method allowed for the calculation of the BS of cellular paperboard based on the mechanical properties of the paper used for its production. The second method allowed for the estimation of the BS of cellular paperboard based on the bending stiffness of other honeycomb paperboards with the same raw material composition and the same core cell size but with different thicknesses. In the first analytical method for the calculation of the bending stiffness of cellular paperboard, which does not include the deflections of the flat layers, the calculation results significantly differ from the measurement results, and they are overestimated. The second of the presented BS calculation methods allowed for a much more accurate assessment of paperboard's bending stiffness depending on its thickness.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34525320

RESUMO

Recycled paperboard contains hundreds of non-evaluated or even unidentified substances that could endanger human health if they turn out to be highly toxic. It seems as unrealistic to evaluate each of them as it is to phase out the use of the problematic ones or sort out the papers and boards introducing them into the recyclate. Therefore, measures should be taken that generally reduce migration into food, such as functional barriers or functional sorbents. A general approach is used for the recycling of plastics, particularly poly(ethylene terephthalate), PET: as not every potential contaminant can be regulated, a pragmatic approach is applied, for PET mainly on the required decontamination efficiency. Criteria are required on the required efficacy of the measures to be taken. Recycled paperboard is used for various types of food contact: mostly contact is through the gas phase (evaporation and recondensation), often indirect through other layers (e.g. internal bags or for transport boxes), seldom in wetting contact. Numerous factors have to be considered. For typical folding boxes and at least strongly dominating gas phase contact, it was proposed that no more than 1% of each contaminant in the recycled paperboard should enter the food. The efficiency of the measures required to comply with this criterion depends on the application. The three main measures are reviewed with regard to this criterion: (i) internal bags with an incorporated functional barrier (successfully used for some time), (ii) a barrier layer on the internal wall of the box (for which the design of the closures might be most critical) and (iii) functional sorbents added to the paperboard (for which the sorbent capacity is critical). For transport boxes, commonly of corrugated board (quantitatively the most important use of recycled paperboard in food contact), an adjusted or different criterion is needed.


Assuntos
Contaminação de Alimentos/análise , Plásticos/química , Regulação do Apetite , Conservação dos Recursos Naturais , Europa (Continente) , Embalagem de Alimentos , Inocuidade dos Alimentos , Humanos , Papel , Reciclagem , Medição de Risco
16.
Materials (Basel) ; 14(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34885607

RESUMO

This paper concerns the analysis of five-layer corrugated paperboard subjected to a four-point bending test. The segment of paperboard was tested to determine the bending stiffness. The investigations were conducted experimentally and numerically. The non-damaging tests of bending were carried out in an elastic range of samples. The detailed layers of paperboard were modelled as an orthotropic material. The simulation of flexure was based on a finite element method using Ansys® software. Several material properties and thicknesses of papers in the samples were taken into account to analyse the influence on general stiffness. Two different discrete models based on two geometries of paperboard were considered in this study to validate the experimental stiffness. The present analysis shows the possibility of numerical modelling to achieve a good correlation with experimental results. Moreover, the results of numerical estimations indicate that modelling of the perfect structure gives a lower bending stiffness and some corrections of geometry should be implemented. The discrepancy in stiffness between both methods ranged from 3.04 to 32.88% depending on the analysed variant.

17.
Molecules ; 26(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34684902

RESUMO

Lignin derivatives have potential as antioxidants in advanced packaging materials through their ability to scavenge oxygen in reactions catalyzed by phenol-oxidizing enzymes, such as laccase. The effects of size fractionation of lignosulfonates on laccase-catalyzed reactions were investigated in experiments with aqueous solutions, films, and coated paperboard. Four industrial lignosulfonate preparations were compared: Feed (unfractionated), Prod (5-60 kDa enriched), Conc (≥60 kDa enriched), and Perm (≤60 kDa enriched). Extraction of lignosulfonates from films showed that the enzymic reaction increased the average molecular weight from <10,000 to up to 66,000. The enzymatic reaction resulted in an increase in the water contact angle of the films from the range 25-49° to 56-81°. The four preparations showed relatively small differences with regard to their ability to scavenge oxygen in aqueous solution and in experiments with coated paperboards in sealed chambers. Coatings with lignosulfonates where the contents of low-molecular weight material had been reduced (i.e., Prod and Conc) showed improved water resistance after the enzymic reaction. Thus, in both aqueous and solid media, fractionation of lignosulfonates had little effect on oxygen scavenging, but fractionation was beneficial for other reasons, such as improved cross-linking resulting in higher molecular weight and superior water resistance.


Assuntos
Lacase , Lignina , Oxigênio , Antioxidantes/química , Catálise , Lacase/química , Lignina/análogos & derivados , Lignina/química , Peso Molecular , Oxirredução , Oxigênio/química , Fenóis/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-33905306

RESUMO

A comprehensive review of the literature was performed on migration of substances from packaging materials into dry foods, specifically those with surfaces containing no free fats or oils. Historically, migration from food packaging to dry foods has been assumed to be minimal. However, several recent publications have reported concentrations of migrants into dry foods that are substantially higher than anticipated. The goal of this review is to provide a comprehensive summary of recent studies that examined migration to dry foods or dry food simulants, observe and assess common migrants, and report the highest migration values. Focusing on the packaging materials and migrants that exhibit the highest migration values, this review divided the studies into two categories: 1) analysis of food products in commercial packaging taken directly from grocery store shelves, and 2) analysis of food products and food simulants in contact with packaging or other material fortified with known quantities of a migrant. Discussions include the examination of migration testing methods, viability of different food simulants, and variables that affect migration behaviour. These include the physicochemical properties of both the migrant and food (i.e. volatility, molecular size, structure, food composition and particle size) and factors pertaining to the packaging material and the environment (i.e. temperature, humidity, and the presence of a secondary barrier). Information gaps and remaining questions are also identified and discussed.


Assuntos
Contaminação de Alimentos/análise , Embalagem de Alimentos/métodos , Análise de Alimentos , Inocuidade dos Alimentos , Humanos , Hidrocarbonetos/química , Metais/química , Óleo Mineral/química , Papel , Tamanho da Partícula , Processos Fotoquímicos , Ácidos Ftálicos/química , Plásticos/química , Volatilização
19.
Artigo em Inglês | MEDLINE | ID: mdl-33872118

RESUMO

The chloropropanols, monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) are potential contaminants that may be found in food contact materials (FCM) from paper and paperboard that have been treated with certain wet-strength resins. They can migrate from the paper matrix to aqueous food and beverages and, due to their potentially carcinogenic properties, are of increasing interest in quality assurance or official controls of paper-based FCM. We hereby describe an improved method for the analysis of 3-MCPD and 1,3-DCP in water extracts of FCM making use of 1-chloro-3-methoxy-2-propanol (CMP) as a novel internal standard. The LOD and LOQ were determined to be 0.4 µg/L and 1.2 µg/L for both analytes, making the method appropriate for the quantification of 3-MCPD and 1,3-DCP below the current legal limits. The method was applied to an extensive market survey of food contact articles made from paper and paperboard including 674 samples. The survey revealed that a high percentage of the products available on the market (e.g., up to 55% of the analysed drinking straws) exceed the BfR limits with values of up to 327 µg/L 3-MCPD and 20 µg/L 1,3-DCP detected in the cold water extract. Remarkable differences were observed concerning the release of 3-MCPD and 1,3-DCP from different kinds of paper-based FCM products, with drinking straws, cupcake cases, bagasse bowls and kitchen rolls showing particularly high rates (>10%) of non-conformity with the legal limits. A number of samples with especially high concentrations were additionally analysed by hot water extraction, which surprisingly yielded considerably lower results for the release of 3-MCPD and 1,3-DCP than cold water extraction. The results indicate that cold water extraction is the most sensitive method to detect the migration and control the risk of exposure to 3-MCPD and 1,3-DCP.


Assuntos
Contaminação de Alimentos/análise , alfa-Cloridrina/análogos & derivados , alfa-Cloridrina/análise , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Humanos , Limite de Detecção , Extração Líquido-Líquido , Inquéritos e Questionários , Água
20.
Molecules ; 25(14)2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32708406

RESUMO

Horticultural plant residues (tomato, pepper, and eggplant) were identified as new sources for lignocellulose nanofibers (LCNF). Cellulosic pulp was obtained from the different plant residues using an environmentally friendly process, energy-sustainable, simple, and with low-chemical reagent consumption. The chemical composition of the obtained pulps was analyzed in order to study its influence in the nanofibrillation process. Cellulosic fibers were subjected to two different pretreatments, mechanical and TEMPO(2,2,6,6-Tetramethyl-piperidin-1-oxyl)-mediated oxidation, followed by high-pressure homogenization to produce different lignocellulose nanofibers. Then, LCNF were deeply characterized in terms of nanofibrillation yield, cationic demand, carboxyl content, morphology, crystallinity, and thermal stability. The suitability of each raw material to produce lignocellulose nanofibers was analyzed from the point of view of each pretreatment. TEMPO-mediated oxidation was identified as a more effective pretreatment to produce LCNF, however, it produces a decrease in the thermal stability of the LCNF. The different LCNF were added as reinforcing agent on recycled paperboard and compared with the improving produced by the industrial mechanical beating. The analysis of the papersheets' mechanical properties shows that the addition of LCNF as a reinforcing agent in the paperboard recycling process is a viable alternative to mechanical beating, achieving greater reinforcing effect and increasing the products' life cycles.


Assuntos
Lignina/química , Lignina/isolamento & purificação , Nanofibras/química , Papel , Extratos Vegetais/química , Capsicum/química , Solanum lycopersicum/química , Reciclagem , Solanum melongena/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA