Effectiveness of polypropylene film as a barrier to migration from recycled paperboard packaging to fatty and high-moisture food.

The capability of a polypropylene (PP) film barrier to prevent migration of residual contaminants from recycled paperboard into food simulants was studied. Anthracene, benzophenone, methyl stearate and pentachlorophenol were chosen as chemical surrogates to represent classes of contaminants likely to be found in recycled paper/paperboard. Each surrogate was spiked into a test specimen made of seven thin virgin paper layers at concentrations of 1-50 mg kg(-1). Test specimen were dried, stacked and sandwiched with PP films, laminated with PP film and then subjected to migration experiments using a compression cell maintained at 100 degrees C for 2 h. The concentration of the surrogates in the test specimen and in 95% ethanol, isopropanol and 10% ethanol food-simulating solvents was determined by gas chromatography with flame ionization and electron capture detection. The results show that although the concentrations of the surrogates in the food simulants decreased with an increase in PP film thickness, they were still high and generally resulted in dietary concentrations >0.5 microg kg(-1), the level that US Food and Drug Administration would equate with negligible risk for a contaminant migrating from food packaging. Only at the lowest spiking level (1 mg kg(-1) benzophenone) did migration from the paperboard through a 0.127-mm PP film result in a dietary concentration of 相似文献   

Recycled paperboard with a barrier layer for food contact: set-off during stacking or reeling. Analytical method and preliminary results

The use of recycled paperboard for packaging dry foods is in the interest of sustainability of resources, but in most applications, the food must be protected against contamination, such as by a functional barrier on the internal surface of the paperboard box. After application, the paperboard is usually stacked or reeled before making boxes. During this period, the food-contact surface of the barrier layer is in contact with the outer side of the paperboard, which may result in set-off and subsequent contamination of food. A method is described for the determination of this path of migration, based on the taped format also used for the measurement of the barrier efficiency. Recycled paperboard containing the three surrogate substances n-heptadecane, 4-methyl benzophenone and dipropyl phthalate was taped to the food-contact side of the barrier layer. Pressure onto the test packs did not seem to be a relevant parameter. After periods of interest, a piece of the paperboard with the barrier layer was extracted and analysed for the surrogate substances. Another piece may be brought into contact with silicone paper to simulate the transfer to food. After 2 weeks at 60°C (simulating about 1 year at 25°C), set-off and the transfer to the silicone paper exceeded 1% for all barrier materials tested, but after 6 weeks at 40°C (around half a year at 25°C), set-off remained below 1% for all barrier layers except a multilayer with polyethylene on the food-contact surface. The preliminary conclusion is that set-off should be taken seriously, but may be kept low enough to provide sufficient protection of the packed food.     

SiOx layer as functional barrier in polyethylene terephthalate (PET) bottles against potential contaminants from post-consumer recycled PET

The barrier effect of a silicon oxide (SiOx) coating on the inner surface of PET bottles, in terms of the ability to reduce the migration of post-consumer compounds from the PET bottle wall into food simulants (3% acetic acid and 10% ethanol), was investigated. The barrier effect was examined by artificially introducing model substances (surrogates) into the PET bottle wall to represent a worst-case scenario. Test bottles with three different spiking levels up to approximately 1000 mg kg(-1) per surrogate were blown and coated on the inner surface. The SiOx-coated bottles and the non-coated reference bottles were filled with food simulants. From the specific migration of the surrogates with different bottles wall concentrations, the maximum surrogate concentrations in the bottle wall corresponding to migration of 10 microg l(-1) were determined. It was shown that the SiOx coating layer is an efficient barrier to post-consumer compounds. The maximum bottle wall concentrations of the surrogates corresponding to migration of 10 microg l(-1) were in the range of 200 mg kg(-1) for toluene and approximately 900 mg kg(-1) for benzophenone. Consequently, the SiOx coating allows use of conventionally recycled post-consumer PET flakes (without a super-clean recycling process) for packaging aqueous and low alcoholic foodstuffs (under cold-fill conditions) and protects food from migration of unwanted contaminants from post-consumer PET.     

Migration of bisphenol A and benzophenones from paper and paperboard products used in contact with food

Migration of bisphenol A (BPA) and benzophenones, i.e., benzophenone (BZ), 4-(dimethylamino)benzophenone (DMAB), Michler's ketone (MK) and 4,4'-bis(diethylamino)benzophenone (DEAB), from 21 paper and paperboard products (15 recycled paperboard boxes and 6 virgin paper products) used in contact with food was examined. Migration levels of compounds from recycled paperboard were compared under various food-simulating conditions. BPA showed the highest migration into 20% ethanol and benzophenones into 95% ethanol. No compounds migrated from virgin paper products, but compounds did migrate into food simulants from recycled paperboard food boxes. BPA migrated into 20% ethanol from all recycled paperboard food boxes between 1.0 and 18.7 ng/mL. Into 95% ethanol, migration of BZ was observed in 8 samples (1.0-18.9 ng/mL), DMAB in 12 samples (1.2-3.7 ng/mL), MK in 13 samples (1.9-9.0 ng/mL), and DEAB in 13 samples (1.0-10.6 ng/mL). The highest migration level was 27.2 ng/mL and most of the migration levels were below 10 ng/mL. These values are sufficiently low compared with the TDI and NOAEL levels. Moreover, the amount of food in daily meals that comes into contact with paperboard products is relatively small. Consequently, it was concluded that there was no safety concern regarding the tested compounds in recycled paperboard food boxes.     

Recycled paper–paperboard for food contact materials: Contaminants suspected and migration into foods and food simulant

Contaminant residues in food packaging is a new challenge of our time, as it may pose a threat for consumers. Higher levels of contaminants were observed in food packaging made by recycled materials, even if little information is available for some groups of contaminants. The present study proposes a procedure for analyzing three different groups of organic contaminants in recycled paper and paperboard. Seventeen commercial samples were analyzed for the presence of bisphenol A (BPA), bis (2-ethylhexyl) phthalate (DEHP), nonylphenol monoethoxylate (NMP) and nonylphenol di-ethoxilate (NDP). Not all the samples contained all the contaminants; BPA was the only substance present in all the samples. The concentrations detected were quite high and, in most of the cases, in agreement with results reported in previous studies. Substance migration tests from spiked/non-spiked samples for two dry foods and Tenax® food simulant were undertaken. BPA migration quotients were always lower than 1%, whereas the migration quotients of DEHP were higher than 2.0%. The highest nonylphenols migration quotients were 6.5% for NMP and 8.2% for NDP. Tenax® simulates well the contaminants migration from paperboard to dry food, in some cases being even more severe than the food.     

Migration of mineral oil,photoinitiators and plasticisers from recycled paperboard into dry foods: a study under controlled conditions

Migration from recycled paperboard was monitored after 2, 4 and 9 months of storage for six test foods industrially packed in five configurations, four with internal plastic films. After 9 months, the migration of mineral oil saturated hydrocarbons into foods directly packed in the paperboard amounted to 30–52 mg/kg, which corresponded to 65%–80% of those of a volatility up to that of the n-alkane C₂₄ in the paperboard. The concentration of the migrated aromatic hydrocarbons in the foods ranged from 5.5 to 9.4 mg/kg. More than half of this migration occurred in the first 2 months. Differences between the foods amounted to mostly less than a factor of 2 and seemed to be related to porosity or permeability more than fat content. Nine photoinitiators were detected in the paperboard, of which eight migrated into the packed food at up to 24%. Several plasticisers were present in the recycled paperboard, but only butyl phthalates showed significant migration. After 9 months, up to 40% of diisobutyl phthalate and 20% of dibutyl phthalate migrated into the food with direct contact. The internal polyethylene film hardly slowed migration, but the film and the tray absorbed approximately three times more mineral oil than the food, despite constituting merely 4% of the mass of the pack. Oriented polypropylene strongly slowed migration: The highest migration of saturated hydrocarbons measured after 9 months (2.3 mg/kg) corresponded to only 3% of the content in the paperboard and included migrated polyolefin oligomeric saturated hydrocarbons. Coating of polypropylene with an acrylate further slowed the migration, but the migration from the paperboard was still detectable in four of the six samples. Polyethylene terephthalate was a tight barrier.     

Bio-based coatings as potential barriers to chemical contaminants from recycled paper and board for food packaging

Partition and diffusion experiments were carried out with paper and board samples coated with different biopolymers. The aim was to evaluate the physicochemical behaviour and barrier properties of bio-coatings against migration of typical contaminants from recycled paper packaging. Focus was directed towards water-based, renewable biopolymers, such as modified starches (cationic starch and cationic waxy starch), plant and animal proteins (gluten and gelatine), poured onto paper with an automatic applicator. Additionally, a comparison with polyethylene-laminated paper was performed. Microstructural observations of the bio-coated paper allowed the characterisation of samples. From the partitioning studies, considerable differences in the adsorption behaviour of the selected contaminants between bio-coated or uncoated paper and air were highlighted. For both the polar and non-polar compounds considered (benzophenone and diisobutyl phthalate, respectively), the lowest values of partition coefficients were found when paper was bio-coated, making it evident that biopolymers acted as chemical/physical barriers towards these contaminants. These findings are discussed considering the characteristics of the tested biopolymers. Diffusion studies into the solid food simulant poly 2,6-diphenyl-p-phenylene oxide, also known as Tenax^®, confirmed that all the tested biopolymers slowed down migration. The Weibull kinetic model was fitted to the experimental data to compare migration from paper and bio-coated paper. Values found for β, an index determining the pattern of curvature, ranged from 1.1 to 1.7 for uncoated and polyethylene paper, whereas for bio-coated papers they ranged from 2.2 to 4.9, corresponding to the presence of an evident lag phase due to barrier properties of the tested bio-coatings.     

SiO x layer as functional barrier in polyethylene terephthalate (PET) bottles against potential contaminants from post-consumer recycled PET

The barrier effect of a silicon oxide (SiO _x ) coating on the inner surface of PET bottles, in terms of the ability to reduce the migration of post-consumer compounds from the PET bottle wall into food simulants (3% acetic acid and 10% ethanol), was investigated. The barrier effect was examined by artificially introducing model substances (surrogates) into the PET bottle wall to represent a worst-case scenario. Test bottles with three different spiking levels up to ～1000 mg kg^?1 per surrogate were blown and coated on the inner surface. The SiO _x -coated bottles and the non-coated reference bottles were filled with food simulants. From the specific migration of the surrogates with different bottles wall concentrations, the maximum surrogate concentrations in the bottle wall corresponding to migration of 10 µg l^?1 were determined. It was shown that the SiO _x coating layer is an efficient barrier to post-consumer compounds. The maximum bottle wall concentrations of the surrogates corresponding to migration of 10 µg l^?1 were in the range of 200 mg kg^?1 for toluene and ～900 mg kg^?1 for benzophenone. Consequently, the SiO _x coating allows use of conventionally recycled post-consumer PET flakes (without a super-clean recycling process) for packaging aqueous and low alcoholic foodstuffs (under cold-fill conditions) and protects food from migration of unwanted contaminants from post-consumer PET.     

Effect of relative humidity on the migration of benzophenone from paperboard into the food simulant Tenax® and modelling hereof

The aim of this study was to investigate the effect of relative humidity on the migration of benzophenone from paperboard into the food simulant Tenax®. Kinetic migration investigations were carried out with three relative humidities in the interval between 39% and >73%. All investigations were carried out at a constant temperature of 34°C. It was found that the migration of benzophenone after more than 30 days was 4.8 times higher at a relative humidity of 64%–71%, and 7.3 times higher at a relative humidity of >73%, compared with that at a relative humidity of 39%–49%. Diffusion and partition coefficients were derived from the results by using a software for modelling migration in multilayer materials. Both the diffusion coefficient and the partition coefficient, between paperboard and Tenax®, decrease with increasing relative humidity. The experimental results were correctly modelled only when the paperboard was regarded as a one-layer system as compared with a two-layer system: where the main part of the paperboard (B1) has a high diffusion rate and a thin part of the paperboard (B2) in contact with the foodstuff has a lower diffusion rate.     

Migration of dehydroabietic and abietic acids from paper and paperboard food packaging into food-simulating solvents and Tenax TA

An investigation was undertaken to establish the concentration in paper products of dehydroabietic (DHA) and abietic (AA) resin acids, present in rosin, which are major toxicants of pulp- and paper-mill effluent. Their migration was studied from paper and paperboard products into various food-simulating solvents and the substitute fatty food simulant Tenax TA (modified polyphenylene oxide). DHA and AA were detected in five of 10 virgin paper products and in all 10 recycled paperboard products for food-contact use at concentrations of 14-500 and 110-1200 µg/g, respectively. In virgin paper products, the highest migration was into 95% ethanol or heptane, with negligible or no migration into other solvents. In recycled paperboard products, migration was highest into 95% ethanol, but was also observed into 20% ethanol, water and heptane. Migration to Tenax TA was also observed and the migration level increased with time. The maximum migration levels of DHA and AA into food simulants were 0.853 and 3.14 µg/g, respectively. The results suggest that, in the worst case, the daily intake of DHA and AA from paper and paperboard products was 50 times lower than the tolerable daily intake of rosin.     

Migration of plasticizers phthalates, bisphenol A and alkylphenols from plastic containers and evaluation of risk

This study investigates the potential migration of plasticisers, plastic components and additives from several plastic water bottles. Compounds studied were phthalates (dimethyl phthalate, di-n-butyl phthalate, benzylbutyl phthalate, bis(2-ethylhexyl) phthalate), bis(2-ethylhexyl) adipate, octylphenol, 4-nonylphenol and bisphenol A. Polycarbonate (PC), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polystyrene (PS) plastics used in the water bottling sector were tested using three kinds of total or specific migration tests: (1) standard method UNE-EN ISO 177; (2) ultrasonic forced extraction; and (3) standard method UNE-EN 13130-1. In addition, bottled waters contained in different plastic materials were analysed to determine the potential migration of target compounds in real conditions. In all cases, samples were solid-phase extracted using Oasis HLB 200 mg cartridges and analysed using GC-MS in scan-acquisition mode. Bisphenol A and 4-nonylphenol were detected in incubated samples, indicating that migration from food plastics can occur at the experimental conditions tested. The total daily intake was calculated according to the levels detected in bottled water and the assessment of the consumers' risk was evaluated taking into consideration toxicological and legislative values.     

Activated carbon added to recycled paperboard to prevent migration into food: approach for determining efficacy,and first results

Catcherboard MB12® from Smurfit Kappa is a recycled paperboard incorporating activated carbon to reduce the release of contaminants into food. An approach is proposed to determine the efficacy of the activated carbon. Sorption into activated carbon increases the concentration ratio paperboard/food (distribution coefficient) and reduces the migration rate, i.e. prolongs the time for equilibration. Using silicone paper as food simulant, the concentration ratio was increased by a factor of at least 1000 compared to recycled paperboard without activated carbon, which is sufficient to meet the 1% criterion proposed for barriers. Sorbents have limited capacity. A load with in total 4000 mg surrogate substances/kg paperboard (in addition to the material from the paperboard) exceeded the capacity: concentration ratios were reduced and the release of paperboard constituents increased. Capacity is consumed by constituents from the printing inks and the packed food. Total amounts of substances in dry foods of sufficient volatility to potentially migrate into the paperboard through the gas phase at ambient temperature were determined by GC-FID. For the large majority of the dry foods, these amounts were clearly below the capacity limit even under the exaggerated assumption of total transfer. Migration of mineral oil hydrocarbons into cat food over up to 1 year was not detectable at 1 mg/kg. It is concluded that recycled paperboard with activated carbon is promising for respecting the 1% criterion stipulated for functional barriers to avoid food contamination from recycled paperboard.     

Properties of Poly(lactide)-Coated Paperboard for the Use of 1-Way Paper Cup

ABSTRACT:  Poly(lactide)-coated paperboards were prepared by a solution coating method, and the effect of coating to improve properties of paperboard used for the manufacturing of 1-way paper cups was tested. Surface of PLA-coated paperboards was smooth and shiny like PE-coated paperboard, and the coating weight and thickness increased linearly with increasing PLA concentration of coating solution. Tensile strength (TS) and elongation at break (E) of the paperboard also increased after PLA coating. Water vapor barrier or water-resistant properties tested, such as water vapor permeability (WVP), water absorptiveness (WA), and contact angle (CA) of water drop, indicated that water resistance of the paperboard was improved through surface coating with PLA. The increase in water resistance of PLA-coated paperboards was mainly due to the hydrophobicity of PLA and the improvement of water barrier properties increased depending on the PLA concentration. In addition, PLA-coated paperboard showed strong heat sealing property when coated with more than 1 w/v% of PLA. Wet strength of PLA-coated (3, w/v%) paperboard was comparable to or greater than that of PE-coated paperboard. All the test results indicated that the PLA-coated paperboard can be exploited for the manufacturing of 1-way paper cups as an alternative to the PE-coated paperboard.     

纸质包装材料中有机污染物向固体食品模拟物的迁移行为分析

利用气相色谱-质谱(GC-MS)联用技术对苯酚、十二烷基苯、2,6-二异丙基萘(2,6-Di PNs)、邻苯二甲酸二丁酯(DBP)以及邻苯二甲酸二(2-乙基己基)酯(DEHP)等5种模拟污染物分别在不同温度、不同接触时间的情况下,从牛皮包装纸向固体食品模拟物的迁移行为进行了研究。结果表明在温度相同的情况下,各模拟污染物的迁移率随着接触时间的增长而增大,最终都有达到平衡的趋势。并且模拟污染物的分子量越小,其达到迁移平衡所需要的时间越短,分子量越大,其从纸张中向固体食品模拟物的迁移率越低。另外,非极性模拟污染物的迁移率较极性的高。对相同模拟污染物而言,温度越高,其达到迁移平衡所需要的时间越短,即迁移速度越快。     

Removal of polycyclic aromatic hydrocarbons from water by migration into polyethylene

Water was spiked with three polycyclic aromatic hydrocarbons (PAHs) and filled into a steel diffusion chamber. Low-density polyethylene sheet combined of five polyethylene foils was used as a partition in the chamber. Depth of PAHs migration into the sheet was followed for 143 h, using high performance liquid chromatography with selective fluorimetric detection after extraction of PAHs from the foils peeled off. On the basis of the results obtained, the process of PAHs migration into PE was characterised as a one-dimensional diffusion into polyethylene bulk. The diffusion coefficients were calculated for individual compounds using the second Fick law. It was concluded that PAHs are primarily adsorbed on the polyethylene surface with subsequent migration into bulk polymer. Transportation of PAHs through the bulk can be described satisfactorily by Fickian laws of diffusion and is consistent with the theory of the depth adsorption of PAHs in polyethylene.     

Safety verification for reuse of PET and glass bottles

In order to verify the safety associated with reusing PET and glass bottles, a challenge test was conducted with five surrogate contaminants: 1,1,1-trichloroethane, chlorobenzene, toluene, benzophenone and phenyl cyclohexane. Bottles were filled with a cocktail solution of these contaminants and stored at 50 °C for 7 days, then washed with water and alkaline solutions. Material and migration tests were conducted at each step. The material test results showed that 430-1,440 μg/g of the contaminants were retained after water washing, and that even after washing with a 3.5% NaOH solution, 225-925 μg/g of the contaminants were retained. The migration tests revealed that 0.095-7.35 μg/mL of the contaminants were eluted. Similar tests were conducted with a soft drink ingredient, limonene. The results revealed that 48 μg/g of limonene was retained even after washing with NaOH solution, and that 0.16 μg/mL of limonene was eluted. Conversely, no contaminants were eluted from glass bottles after washing with the NaOH solution. Thus, from the viewpoint of safety and the preservation of content quality, PET bottles are not considered suitable for reuse when compared with glass bottles.     

Study of barrier properties and chemical resistance of recycled PET coated with amorphous carbon through a plasma enhanced chemical vapour deposition (PECVD) process

Many studies have been carried out in order to make bottle-to-bottle recycling feasible. The problem is that residual contaminants in recycled plastic intended for food packaging could be a risk to public health. One option is to use a layer of virgin material, named functional barrier, which prevents the contaminants migration process. This paper shows the feasibility of using polyethylene terephthalate (PET) recycled for food packaging employing a functional barrier made from hydrogen amorphous carbon film deposited by Plasma Enhanced Chemical Vapour Deposition (PECVD) process. PET samples were deliberately contaminated with a series of surrogates using a FDA protocol. After that, PET samples were coated with approximately 600 and 1200 Angstrons thickness of amorphous carbon film. Then, the migration tests using as food simulants: water, 10% ethanol, 3% acetic acid, and isooctane were applied to the sample in order to check the chemical resistance of the new coated material. After the tests, the liquid extracts were analysed using a solid-phase microextraction device (SPME) coupled to GC-MS.     

PVC保鲜膜中增塑剂DOP在水中迁移规律研究

主要研究了不同几种MA条件下3种PVC保鲜膜中增塑剂DOP在蒸馏水中的迁移规律(模拟果蔬MA保鲜的环境),以PE保鲜膜对照。结果表明,3种PVC保鲜膜包装的蒸馏水中增塑剂DOP有不同程度的迁移,而在PE膜包装的水中没有检测到DOP的迁移。PVC保鲜膜DOP的迁移量与温度、时间、保鲜膜DOP的含量、保鲜膜的厚度有一定的相关性。     

Internal bags with barrier layers for foods packed in recycled paperboard: recent progress

Internal bags for packaging dry foods into boxes of recycled paperboard, collected in Dresden and Zurich in June 2013, were investigated with regard to the layer composition and the barrier efficiency against substances migrating from the recycled fibers. The layers were identified by microtome cuts and Fourier transform infrared spectroscopy, often after wet-chemical separation of the layers. The barrier efficiency was tested with five surrogate substances and classified between 1 and 5, with class 1 having no significant barrier effect, 4 being a virtually tight barrier consisting of polymeric material and 5 including an aluminum foil. Merely 17 of the 87 bags (20 %) consisted of paper or polyethylene that constituted insignificant barriers. Bags of oriented polypropylene, substantially reducing migration (class 2), were encountered in 32 % of the packs; those with more efficient, but still incomplete barriers (class 3) in 16 % and virtually tight barriers (classes 4 and 5) in 32 % of the products. This is a strong move toward efficient barriers compared to the findings in 2010. Efficient or tight barriers were found for nearly all food types, which suggests that there are no important technical obstacles against the inclusion of a barrier layer into all bags to protect the food against contamination from the recycled paper board.     

CE-04剥离剂在玻璃卡纸中的应用及评价

通过采用性能良好的CE-04剥离剂,使纸张涂层在湿状态下容易粘结在铸涂缸表面,形成很高的纸面光泽度,而干燥后又赋予纸张卓越的剥离性能,从而提高了纸机的操作性能和生产效率;同时选择了恰当的加入点,避免了铸涂卡纸因发生粘缸而引起的麻坑点、针孔等纸病,提高了成纸品质.