Food Contact Applications Research Articles

Food firms push to phase out bisphenol A

Facing mounting pressure from consumer advocates and environmental activists, Campbell Soup and Del Monte Foods have announced timetables for replacing bisphenol A (BPA)-based coatings in food cans. Epoxy-based coatings, made from the raw materials BPA and epichlorohydrin, have long been favored for the interior lining of food cans because they are flexible, resist corrosion, and don’t alter the flavor of the foods inside. But the possibility that BPA in high enough doses may act as an endocrine disruptor has made its use in food-contact applications controversial. Polycarbonate, also made with BPA, has been phased out of baby bottles, and EPA banned BPA for infant formula cans. Food companies have pledged in recent years to seek alternatives across their product lines. Campbell promised four years ago to phase out BPA-containing coatings. Now the firm says it has delivered about 2 million cans lined instead with acrylic- and polyester-based coatings. The company

Efficacy of Cinnamaldehyde Against Enteric Viruses and Its Activity After Incorporation Into Biodegradable Multilayer Systems of Interest in Food Packaging.

Cinnamaldehyde (CNMA), an organic compound that gives cinnamon its flavor and odor, was investigated for its virucidal activity on norovirus surrogates, murine norovirus (MNV) and feline calicivirus (FCV), and hepatitis A virus (HAV). Initially, different concentrations of CNMA (0.1, 0.5 and 1%) were individually mixed with each virus at titers of ca. 6-7 log10 TCID50/ml and incubated 2h at 4 and 37°C. CNMA was effective in reducing the titers of norovirus surrogates in a dose-dependent manner after 2h at 37°C, while HAV titers were reduced by 1 log10 after treatment with 1% of CNMA. When incubation time was extended, HAV titers were reduced by 3.4 and 2.7 log10 after overnight incubation at 37°C with 1 and 0.5% of CNMA, respectively. Moreover, this paper analyzed, for the first time, the antiviral activity of adding an active electrospun interlayer based on zein and CNMA to a polyhydroxybutyrate packaging material (PHB) in a multilayer form. Biodegradable multilayer systems prepared with 2.60mg/cm(2) (~9.7%) of CNMA completely inactivated FCV according to ISO 22196:2011, while MNV titers were reduced by 2.75 log10. When the developed multilayer films were evaluated after one month of preparation or at 25°C, the antiviral activity was reduced as compared to freshly prepared multilayer films evaluated at 37°C. The results show the excellent potential of this system for food contact applications as well as for active packaging technologies in order to maintain or extend food quality and safety.

Supercritical CO2 extraction of contaminants from polypropylene intended for food contact: Effects of contaminant molecular structure and processing parameters

Supercritical CO2 (SCCO2) extraction has been employed to remove model molecules (surrogates) which simulate the real and potential contaminants which can be present into recycled post-consumer polypropylene, limiting the recyclability for food contact applications. Different substances covering a wide range of molecular weights were extracted and evaluated. The effects of contaminant molecular structure and several processing parameters (pressure, temperature, extraction time, solvent flow rate, and matrix shape and size) upon extraction rate were investigated. The operating conditions studied were: pressure ranges of 100–300bar, temperature ranges of 50–90°C, indicating CO2 densities varying from 0.20 to 0.87g/mL, and solvent flow rate ranges of 60–160mL/min. Two shapes of contaminated material were studied: pellets and films (thickness ranges of 100–300μm). Quantitative results for extraction kinetics have been obtained by gas chromatography. High extraction yields (100%) were achieved with films at restricted extraction times and, likewise, with pellets at reasonable extraction times. Operating conditions of 200bar, 90°C and 7.5h of extraction were sufficient to achieve a complete extraction from pellet matrix (2.5mm of diameter), even for the heaviest contaminant (807g/mol).

Demonstrations of Additive Manufacturing for the Hospitality Industry

Abstract This article demonstrates the potential application of additive manufacturing techniques and technologies in food safe applications for industrial, commercial, and consumer scales. We produced an entirely additively manufactured dinner to demonstrate use cases of the technology. Drawing on additive manufacturing's strengths of low production runs and low-cost geometric complexity, we directly produced tableware of complex form targeted for limited audiences. Current additive manufacturing techniques lack the required process control and certifications for widespread use in food contact applications. The use of coatings can mitigate the concern for prototypes and small-scale production. Directly printing food-related items is of use for tableware in increasing artistry, addressing niche markets, and prototyping. Other researchers in the commercial and private sectors can build upon this work to develop the processes and procedures needed to enable more widespread adoption of 3D printing in food-re...

Safety assessment for octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionate (CAS Reg. No. 2082-79-3) from use in food contact applications

Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (CAS Reg. No. 2082-79-3), currently marketed as Irganox 1076 (I-76), is a sterically hindered phenolic antioxidant used in a variety of organic substrates, including those used in the manufacture of food contact articles. In 2012, the US Food and Drug Administration (USFDA), Office of Food Additive Safety (OFAS), initiated a post-market re-evaluation of the food contact applications of I-76. This project aimed to ensure that current dietary exposures from the use of I-76 in food contact articles are accurately captured and the safety assessment considered all relevant and available toxicological information. To accomplish these aims, the USFDA reviewed the available toxicological studies and chemistry information on food contact applications of I-76. Based on this in-depth analysis, a NOAEL of 64 mg/kg-bw/d (female rats) from a chronic rat study and a cumulative estimated dietary intake (CEDI) of 4.5 mg/p/d, was used to calculate a margin of exposure (MOE) of ∼850. We concluded that the previous and current exposure levels provide an adequate margin of safety (MOS) and remain protective of human health for the regulated uses.

Benzyl butyl phthalate increases the chemoresistance to doxorubicin/cyclophosphamide by increasing breast cancer-associated dendritic cell-derived CXCL1/GROα and S100A8/A9

Phthalates are used as plasticizers in the manufacture of flexible vinyl, which is used in food contact applications. Phthalates have been demonstrated to have an adverse impact on human health, particularly in terms of cancer development. In the present study, we showed for the first time that benzyl butyl phthalate (BBP) potentiates the effect of tumor‑associated dendritic cells (TADCs) on the chemoresistance of breast cancer. Specific knockdown analysis revealed that S100A9 is the major factor responsible for the chemoresistance of doxorubicin/cyclophosphamide induced by BBP-stimulated TADCs in breast cancer. BBP exposure also increased tumor infiltrating myeloid-derived suppressor cell (MDSC) secretion of S100A8/A9, thereby exacerbating the resistance of breast cancer to doxorubicin with cyclophosphamide. In addition, BBP also stimulated the production of CXCL1/GROα by TADCs, which increased the angiogenesis of breast cancer in a mouse model. Inhibition of CXCL1/GROα by a neutralizing antibody, decreased the BBP-induced angiogenesis induced by BBP after chemotherapy in the mouse model. These results, for the first time, provide evidence that BBP influences the efficacy of chemotherapy by remodeling the tumor microenvironment of breast cancer.

Enhanced Quality Control of Recycled Paperboard for Food Packaging

A method is reported for the industrial quality control of recycled paperboard for food contact applications. Benzophenones, phthalates, and diisopropyl naphthalene were selected as contamination markers. These compounds are commonly found in recycled paperboard packaging and are known to migrate even into dry nonfatty foods. The method was used to analyze commercial recycled board and involved sample pretreatment by accelerated solvent extraction, evaporation, and purification of the extract, and analysis by gas chromatography–mass spectrometry. The accelerated solvent extraction yields were compared with those obtained by Soxhlet extraction and extraction by immersion, and the recoveries of optimized procedures were estimated. The optimized method showed good repeatability, intermediate precision, and sensitivity. Because of the simplicity and partial automation, this method has potential application for the characterization of recycled paperboard.

Purification of post-consumer polyolefins via supercritical CO2 extraction for the recycling in food contact applications

Throughout their lifecycle or first use, polyolefins can be exposed to contaminating media which limit their recyclability, especially in food industry, such as packaging. Supercritical carbon dioxide (SCCO2) extraction in dynamic mode is studied as a possible method to purify post-consumer polyolefins. As a first approach, the strategy was to remove the well-known conventional additives (i.e., antioxidant) which are already present in food grade polypropylene (PP) and linear low density polyethylene (LLDPE). The extraction yields and kinetics have been obtained by gas chromatography. A systematic study of the influence of the shape (pellets or films) and the thickness of the materials shows that it is possible to increase the speed of extraction with a thinner material: high yields (100%) are obtained with films at 300bar, 50°C and 5min of extraction. Finally, the potential of SCCO2 extraction was compared to that of traditional liquid extraction with methylene chloride.

Assessing safety of non-intentionally added substances in polymers used for food contact applications

Assessing safety of non-intentionally added substances in polymers used for food contact applications

(Morris Cohen Graduate Student Award of the Corrosion Division) Stainless Steel in Biological Environments – Relation Between Material, Surface Chemistry and Toxicity

Stainless steels are commonly used in a variety of essential applications in our daily-life, for instance as biomaterials and in food contact applications. Even though the corrosion resistance of such grades is high, or very high, alloy components will be released to different extent in contact with biological media of varying composition, acidity and metal complexation capacity, a process that may induce adverse toxicological effects. Research activities have focused to quantitatively determine, and kinetically and mechanistically assess the metal release process in relation to material and surface properties of stainless steels of different grade as massive sheet and as powders in contact with biological systems of relevance for human exposure. Surface-protein interactions have been addressed from a combined surface chemistry, corrosion and material science and toxicological approach. Generated findings clearly show that both bulk and surface oxide properties such as phase, structure, morphology, chemical and electrochemical stability, largely influence the metal release process, biointerfacial interactions, bioavailability of released metals, and subsequent toxicity. For example, the cooling-rate dependent surface oxide speciation (surface oxide thickness, composition, phase and phase distribution, crystallinity etc.) of stainless steel particles strongly determines whether the dominant mechanism of metal release in complexing biological environments is corrosion-controlled or ligand-induced chemical dissolution. Research findings are of vital importance for risk assessments of stainless steel and alloys, to understand adsorption phenomena on stainless steel, metal release and corrosion processes, and the influence of surface oxide speciation on metal release, corrosion, and toxicity.

Use of nanoclay platelets in food packaging materials: technical and cytotoxicity approach

Two organo-modified clays for food contact applications were developed to produce hydrophobically modified montmorillonite and hence to obtain better compatibility between the biopolymer and the filler (nanoclay). These nanofillers were characterised by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction and thermogravimetric analysis (TGA) in order to study their composition, structure and thermal stability. The fillers were used to reinforce polylactic acid (PLA) bottles, which were characterised using different techniques such as mechanical and barrier properties, morphology and thermal stability. The results were compared with conventional PLA bottles. The use of the modified clay in PLA bottles was found to lead to an improvement in mechanical and barrier properties. Finally, cytotoxicity tests were carried out with the organo-modified clays using Caco-2 and HepG2 cell lines, with uptake of neutral red as a basal cytotoxicity biomarker.

Safety evaluation of mechanical recycling processes used to produce polyethylene terephthalate (PET) intended for food contact applications

The development of a scheme for the safety evaluation of mechanical recycling processes for polyethylene terephthalate (PET) is described. The starting point is the adoption of a threshold of toxicological concern such that migration from the recycled PET should not give rise to a dietary exposure exceeding 0.0025 μg kg–1 bw day–1, the exposure threshold value for chemicals with structural alerts raising concern for potential genotoxicity, below which the risk to human health would be negligible. It is practically impossible to test every batch of incoming recovered PET and every production batch of recycled PET for all the different chemical contaminants that could theoretically arise. Consequently, the principle of the safety evaluation is to measure the cleaning efficiency of a recycling process by using a challenge test with surrogate contaminants. This cleaning efficiency is then applied to reduce a reference contamination level for post-consumer PET, conservatively set at 3 mg kg–1 PET for a contaminant resulting from possible misuse by consumers. The resulting residual concentration of each contaminant in recycled PET is used in conservative migration models to calculate migration levels, which are then used along with food consumption data to give estimates of potential dietary exposure. The default scenario, when the recycled PET is intended for general use, is that of an infant weighing 5 kg and consuming every day powdered infant formula reconstituted with 0.75 L of water coming from water bottles manufactured with 100% recycled PET. According to this scenario, it can be derived that the highest concentration of a substance in water that would ensure that the dietary exposure of 0.0025 µg kg–1 bw day–1 is not exceeded, is 0.017 μg kg–1 food. The maximum residual content that would comply with this migration limit depends on molecular weight and is in the range 0.09–0.32 mg kg–1 PET for the typical surrogate contaminants.

Determination of Five (5) Possible Contaminants in Recycled Cardboard Packages and Food Simulants Using Ultrasound Assisted Extraction Coupled to GC-MS

A modified analytical procedure has been developed to test for 5 organic pollutants [benzophenone, 2 diisopropylnaphthalenes (DIPNs) {2,6- and 2,7-diisopropylnapthalene} and 2 hydrogenated terphenyls (HTPs) {m-terphenyl and o-terphenyl}] that can be found as residues in recycled cardboards intended for use as food packaging materials and to test for migration levels of these compounds in a food simulant (Tenax). A main objective was to develop a modified rapid and reliable method for the identification and quantification of these compounds at low concentrations. The method was based on ultrasound-assisted solvent extraction (UAE) followed by gas chromatography-mass spectrometry (GC-MS) analysis. The developed method was applied to analyze 3 commercially available recycled carton board food-packaging materials and also to study the potential migration of the 5 organic pollutants from these materials into Tenax to check if these recycled cardboards can be considered as suitable for use in direct contact with foodstuffs. The limits of detection (LODs) of standard solutions of the 5 compounds were determined at a signal-to-noise ratio of 3. The LODs and the limits of quantification (LOQs) of examined pollutants ranged between 0.005 to 0.5 mg/kg, and 0.1 to 1 mg/kg, respectively. The extremely low amounts of most contaminants that migrate from packaging materials to Tenax indicate that the recycled cardboards tested can be safely used for direct food contact applications.

Food compatibility and degradation properties of pro‐oxidant‐loaded LLDPE film

ABSTRACTTo avoid environmental hazards, packaging industries are aiming to produce biodegradable films for food contact safety and its degradation. LLDPE film containing 1% pro‐oxidant additive was studied for food compatibility in different simulants, at room temperature conditions as per Bureau of Indian Standards (BIS), code of federal regulations (CFR), food and drug administration USA (USFDA), and European Economic Commission directives (EEC) specifications. Overall migration values were well within the specified limits for food contact applications at room temperature filling and storing. The pro‐oxidant loaded LLDPE film was also studied for its degradation behavior with the changes in physical and mechanical properties along with thermal behavior, morphology and infrared spectroscopy. The molecular oxidations of pro‐oxidant‐loaded LLDPE films are severed which increases hydrophilicity. Evidently, the oxidation renders the material much more vulnerable to microbial attack. The combined effect of both photo and bio degradation is most effective for complete degradation of film. The results obtained from these studies revealed that the fine balance (1%) of pro‐oxidant contents in the film guarantees food contact safety and its degradation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39756.

Insight into industrial PLA aging process by complementary use of rheology, HPLC, and MALDI

Nowadays, there is a growing availability of biodegradable industrial materials intended to food contact applications whose service life behavior needs to be further investigated. This article is focused on the degradation of two materials based on polylactic acid. The correlation between the rate of degradation and the amount of trapped degradation products was investigated applying three characterization techniques in parallel, namely rheology, high‐performance liquid chromatography (HPLC), and matrix‐assisted laser desorption/ionization (MALDI). The rate of degradation was studied through the evaluation of their rheological properties and calculation of the number of average molecular weights, and weight‐average molecular weights. Water‐soluble oligomers and lactic acid were quantified by HPLC‐ultraviolet. Changes in cyclic and linear oligomers were monitored by MALDI‐time‐of‐flight mass spectrometry. Specimens of 4‐mm thickness of each biopolymer were subjected to hydrolysis in deionized water up to 6 months at two temperatures, simulating service conditions of food packaging. The diminution in viscosity and consequently in molecular weight distribution (20–60%) showed the degradation of the molecular structure of both polylactic acids. The chain scission was followed through the increasing values of lactic acid and hydrolyzed oligomers (twofold to eightfold), and the predominant signal of the linear oligomers over the cyclic ones with aging. Rheology, HPLC, and MALDI showed to be complementary tools to better understand the changes in the molecular structure. The obtained results showed the necessity of adding suitable stabilizers for each particular food packaging application. Copyright © 2013 John Wiley & Sons, Ltd.

Development of starch/shellac-based composites for food contact applications

The present study aimed at exploiting the unfavorable changes of thermally modified shellac with the idea of developing starch/shellac-based composites intended for food contact applications. On baking shellac samples at 200°C for different time intervals (0–20 min), functional groups and linkages were drastically modified, especially anhydride formation, polyesterification, and ether/acetyl linkage occurrences. These processes caused a marked increase in the glass transition temperatures (from about 33 to 60°C) and melting temperatures (from 175 to about 230°C) but a decreased solubility in ethanol (from 95 to 9%). The addition of shellac into a starch-based formulation for producing shaped bodies in combination with heat could significantly strengthen the composite materials and drastically reduce the water uptake after soaking in both cold water and hot water. Furthermore, application of a food-grade biodegradable coating showed remarkable improvement in terms of water resistance and mechanical strength of the composites. The first attempt at making chopsticks was successful and showed promising results. Nevertheless, forming processes and mold designs of such articles—long narrow tubes—need further study.

A computer‐aided methodology to design safe food packaging and related systems

A specific “Failure Mode, Effects, and Criticality Analysis” (FMECA) methodology has been developed to detect substances, materials, and steps that are critical for the safety of packaging systems used in food contact and related applications. Contamination levels in the finished product beyond acceptable thresholds are screened via a systematic analysis of crossed mass transfer between components and a serialization of mass‐transfer instances during product lifetime. The whole framework, including physical modeling and expert systems, has been integrated within the open‐source simulation software FMECAengine. The whole approach is illustrated on three case studies representative of applications along the food packaging supply chain: (1) identification of critical routes of the contamination by printing ink constituents, (2) concurrent engineering of multipurpose packaging, and (3) application to surveys or control plans. The implementation of this framework within industrial commitments such as compliance with EU regulations and ISO 22000 type food safety management systems is discussed. © 2013 American Institute of Chemical Engineers AIChE J, 59: 1183–1212, 2013

Migration of Acrylic Monomers from Methacrylate Polymers - Establishing Parameters for Migration Modelling

Acrylic acid-based and methacrylic acid-based monomers are widely used for the manufacture of polymers, for polymer dispersions or for other specialty resins. Some of these applications cause interactions between the polymer and contact medium such as food contact materials, eyeglasses, contact lenses or toys. More specifically, migration of monomers from the polymer into the contact medium may occur, which needs to be evaluated for safety purposes. The objective of this study was to investigate the basic diffusion properties of acrylic polymers with respect to representative monomers in order to establish a scientific basis for migration modelling simulating the mass transport of monomers from the polymers when they are in contact with foods, human skin or body fluids such as sweat and saliva. For this purpose, 11 representative acrylic polymers containing five different acrylic monomers (MA, EA, BA, MMA and nBMA) were studied in extensive kinetic migrations experiments in contact with five different contact media (simulants) at three different temperatures (20°C, 40°C and 60°C). The simulants were selected according to the applications: toys were simulated by saliva simulant and articles coming in contact with human skin by sweat simulant. For food contact applications, water (aqueous foods), Miglyol 840 (Sasol, Witten, Germany) (fatty food) and Tenax® (Sigma-Aldrich Corporation, Munich, Germany) (an adsorbent simulating dry foods) were selected. The diffusion coefficients (D) of the monomers in the polymer as well as partition coefficients between polymer and contact media were derived. It was found that those acrylic polymer materials used for rigid plastics applications exhibit extremely low diffusion behaviour, whereas acrylic polymer resins used for coating applications showed somewhat higher diffusion behaviour but this still at very low rates in comparison with other typical polymers used for the manufacture of food packaging materials. As a result, conservative polymer-specific constants in support of migration modelling were established, and the specifications for the model general applicability were determined and specified. The parameter related to the polymers' intrinsic mobility is applicable to model migration of any other organic chemical substances, which may be present in acrylic polymers as potential migrants when they have comparable or higher molecular weights than the studied monomers. Copyright © 2012 John Wiley & Sons, Ltd.

Contamination of Polyvinyl Chloride Cling Films from Cardboard Packaging

An analytical screening was undertaken with the aim of investigating the occurrence of di‐isobutylphthalate (DIBP) in polyvinyl chloride (PVC) cling films for food contact applications and its source of contamination throughout a converting process. Although raw plastic materials used by producers are free from phthalates and analytical evidences confirm their absence after the extrusion process, DIBP can be found in final rolls packaged into cardboard packaging during storage.A solvent extraction Gas Chromatography/Mass Spectrometry (GC/MS) analysis was applied on several intermediate products and at different stages taken from the converting process, with the aim of identifying the source of contamination. Different cardboard cores and folding cardboards made of recycled fibres were analyzed, and some of them resulted highly contaminated by DIBP. The storage of final cling films with these materials increased DIBP transfer into PVC.To investigate the possible DIBP transfer mechanism from contaminated paper and adsorption by plastic materials through the gas phase, kinetic experiments were performed in a model system. Results obtained at 20 °C, 30 °C and 40 °C showed a considerable uptake of DIBP into PVC; Weibull model parameters estimated from the experimental data suggested an initial rate of the process dependent on temperature. In addition, to evaluate the partitioning behaviour, adsorption isotherms of DIBP into paper, PVC and low low density polyethylene (LLDPE) cling film were obtained at 40 °C. Copyright © 2012 John Wiley & Sons, Ltd.

Development of a Method for the Determination of Bisphenol A at Trace Concentrations in Human Blood and Urine and Elucidation of Factors Influencing Method Accuracy and Sensitivity

Bisphenol A (BPA) is an industrial chemical used to make polymers including some used in food contact applications. Virtually complete presystemic clearance of orally administered BPA occurs in humans by metabolism to BPA-glucuronide (BPA-G), but some biomonitoring studies report low concentrations of free (parent) BPA in human blood and urine. Trace contamination of BPA from exogenous sources or hydrolysis of BPA-G to free BPA, either during or after biomonitoring specimen collection, may have contributed to the reported concentrations of free BPA. An analytical method for the determination of free BPA in human blood and urine was developed and validated in two independent laboratories, using the latest generation of high-performance liquid chromatography-tandem mass spectrometry instrumentation to ensure the desired high sensitivity and selectivity. The method was designed to account for and/or eliminate background contamination from all sources and demonstrated that contamination could occur from devices used for specimen collection or storage, as well as other sources. The method employed an internal standard (BPA-d(8)) and demonstrated accuracy and reproducibility in both matrices fortified with BPA or a surrogate analyte ((13)C-BPA) at a low quantitation limit (0.1-0.2 ng/mL). For validation, five replicate samples were analyzed to evaluate reproducibility. Importantly, it was demonstrated that the conditions of the method did not result in the hydrolysis of BPA-G to free BPA, another possible source of error in BPA analysis. Application of the principles defined by this method will be critical to assure valid analytical results in any future biomonitoring studies.