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Although most new biomaterials for food industry applications are labelled ‘100% natural fabrication’ and ‘chemical-free’, certain compounds may migrate from those materials to the food, compromis- ing the organoleptic characteristics and safety of the product. In this work, the degree of compound migration from dishes made with four different biomaterials: bamboo, palm leaf, wood and wheat pulp was investigated. Migration tests were carried out using three food simulants, 10% ethanol (sim- ulant A), 3% acetic acid (simulant B), and 95% ethanol (simulant D2). Unequivocal identification of non-intentionally added substances (NIAS) is challenging even when using high-resolution mass spectrometry techniques however, a total of 25 different non-volatile compounds from the migration tests were identified and quantified using Ultra-high performance liquid chromatography coupled to ion mobility quadrupole time-of-flight mass spectrometry (UPLC-IMS-MS). In the bamboo samples three oligomers, cyclic diethylene glycol adipate, 3,6,9,16,19,22-hexaoxabicyclo[22.3.1]-octacosa-1(28),24,26- triene-2,10,15,23-tetrone and 1,4,7,14,17,20-hexaoxacyclohexacosane-8,13,21,26-tetrone exceeded the specified limits of migration.

This article presents fabric phase sorptive extraction (FPSE) as a simple and effective pre-concentration method for the enrichment of acrylate compounds in different food simulants and subsequent analysis of the extracts by ultra-high-performance liquid chromatography with mass spectrometric detection (UPLC-MS). Acrylate compounds come from acrylic adhesives used commonly for sticking the paper labels on polyethylene terephthalate (PET) bottles and therefore, they may exist in recycled polyethylene terephthalate (rPET). Four acrylates were studied: ethylene glycol dimethacrylate (EGDM), pentaerythritol triacrylate (PETA), triethylene glycol diacrylate (TEGDA) and trimethylolpropane triacrylate (TMPTA). Five different types of FPSE media coated with different sol-gel sorbents were studied and finally sol-gel polyethylene glycol- polypropylene glycol-polyethylene glycol triblock copolymer (PEG-PPG-PEG) coated FPSE media was chosen for its satisfactory results. The optimal conditions affecting the extraction efficiency of compounds were determined in three different food simulants. Statistical evaluation of this method reveals good linearity and precision. Under the optimized conditions, the method provided limits of detection of the compounds in the range of (0.1–1.9 ng g−1, 0.1–1.2 ng g−1, 0.2–2.3 ng g−1) in EtOH 10%, HAc 3% and EtOH 20% and the enrichment factor values (EFs) after applying N2 were in the range of 11.1–25.0, 13.8–26.3, 8.3–21.9, in simulants A, B and C respectively. The optimized method was applied successfully to analyze thirteen types of recycled PET samples. Acrylates were found in some of the samples at ng g−1 levels.

The rapid growth of polymer technology in the field of food contact materials (FCMs) needs to be supported by continuous improvement in material testing, in order to ensure the safety of foodstuff. In this work, a range of different starch-based biopolymer samples, in the shape of pellets and retail samples (cups and dishes) were studied. The optimized extraction process was performed on three different pellet shapes: pellets with no modification (spherical), pellets shattered under high pressure (lentils), and pellets cryogenically ground (powder). The analysis of unknown volatile and semi-volatile compounds was carried out by gas chromatography-mass spectrometry, using both electron ionization with a single quadrupole mass analyzer (GC-EI-MS), and atmospheric pressure gas chromatography with a quadrupole/time of flight mass analyzer (APGC-Q/ToF). The identification process was implemented using the latest advances in the understanding of APGC ionization pathways. Chemical migration was also assessed on prototype samples using the food simulants: ethanol 10% v/v, acetic acid 3% w/V, ethanol 95% v/v, isooctane, and vegetable oil. Each migration test was performed three consecutive times, as recommended for materials intended for repeated use.

Bioplastic materials are increasingly used due to its benefits for the environment preservation. Among them, food packaging materials based on polylactic acid (PLA) are among the most employed. In this work, a sample treatment methodology based on dissolution/precipitation has been optimized, selecting finally dichloromethane/ethanol as solvent/antisolvent system. The extracts obtained were analysed by UPLC-MS(QTOF), that allowed the identification of the main PLA non-volatile components. The recovery results were between 100.9 to 114.0%. The methodology was applied to the analysis of pellets and films of a PLA-polyester blend sample. A total of 37 different compounds were detected, where the four compounds with the highest intensity in pellet samples were cyclic oligomers coming from the polyester part of the blend and composed by adipic acid (AA), phthalic acid (PA) and butanediol (BD). Migration experiments to 3 food simulants were also performed: ethanol 95% (v/v), ethanol 10% (v/v) and acetic acid 3% (w/v). The results showed that in addition to those compounds previously detected in the film, new compounds coming from the reaction of PLA components with food simulants were present in migration solutions.

61 different non-volatile compounds were determined in Agaricus Bisporus sliced mushrooms using UHPLC/Q-TOF with MS(E) technology. Both positive and negative electrospray ionization were applied. Chemical profile of three parts of mushroom was created: cap, gills and stipe. The analysed mushrooms were oxidized to identify the non-volatile markers in their parts. MarkerLynx(®) was proposed as a powerful tool to distinguish mushrooms purchased in different countries (Spain and Portugal) by determining their non-volatile markers. Some metabolites were identified. Surprisingly a mix of polyethylene glycols (PEGs) was detected in cap and gills of mushrooms. Whole mushrooms were considered as vegetable resistant to migration from packaging compounds. Additionally migration tests were performed to determine the source of migrating compounds.

Within the family of polycyclic aromatic hydrocarbons (PAHs), nitrated derivatives are of particular interest in environmental science because they have well-known carcinogenic and mutagenic effects. They are in fact more toxic than their parent PAHs. One valuable diagnosis of atmospheric pollution can be obtained using biomonitors such as mosses. These biomonitors can provide information about air pollution over long periods of time in wilderness areas. Thus, they can serve as monitors of the atmospheric transport of pollutants. In this study, atmospheric pressure gas chromatography coupled to a quadrupole hyphenated to a time of flight mass spectrometer (APGC–MS/Q-TOF) has been examined for the identification of target analytes (15 PAHs and 8 NPAHs) for subsequent use in the analysis of mosses. Working ranges in low μg g −1 concentration levels were obtained with most correlation coefficients higher than 0.999. All LODs were in the 0.007–0.035 μg g −1 range and higher LODs (0.035 μg g −1 ) were obtained for the less volatile PAHs with higher mass and retention times: benzo(g,h,i)perylene, dibenz(a,h)anthracene and indeno(1,2,3-c,d)pyrene. These LODs are of importance for the intended use, biomonitoring, especially taking into account that NPAHs are commonly found at very low concentration levels. Recoveries from mosses ranged from 75 to 98%. Intraday and interday precision ranged from 1.8 to 11.1% RSD and from 2.4 to 16.7% RSD, respectively. Very low concentrations of NPAHs were found in mosses compared to those of PAHs. All these data were used for pattern recognition of the pollutant source. The results are shown and discussed.

Primary aromatic amines (PAAs) have been broadly studied due to their high toxicity. In this work a method for the analysis of 22 PAAs in aqueous simulants has been developed. The method is based on a solid-phase extraction step using cation-exchange cartridges and the subsequent analysis of the extracts by ultra-high-performance liquid chromatography with mass spectrometric detection. The recoveries obtained for all the amines analyzed ranged between 81 and 109%, linear range was between 0.03 and 75 microg L(-1), with the RSD values between 4.5 and 13.4% and an average value of 7.5% and limits of detection at microg L(-1) level. The method has been applied to two real samples obtained from migration experiments of polyurethane based laminates to simulant B (water with 3% (w/v) acetic acid) which represents the worst case for the migration of aromatic amines. The main amines found in both samples were methylenedianiline isomers, obtained from the corresponding residual diisocyanates used during polyurethane adhesive polymerization. The total amine concentration found was 26 and 6.3 microg of aniline equivalents per kg of food simulant.

The determination of specific migration in the three aqueous food simulants (water, 3% acetic acid and 10% ethanol) from experimental active packaging polypropylene-based films containing natural essential oils as active agents has been carried out for the first time by a two-phase hollow fibre liquid phase microextraction (HFLPME). Due to the high number of variables involved, an experimental design has been applied. High throughput, with six samples running simultaneously in a highly automated system working in dynamic extraction mode, has been achieved. The main analytical characteristics are detection limits as low as 0.01 μg kg −1 , linearity higher than 0.99 for almost 5 magnitude orders, average precision below 16% as RSD and concentration factors ranging from 4 to 189. Migration of 43 compounds including terpenes, alkanes, plastic additives and degradation compounds is reported. According to the results obtained and European legislation, the packaging prototypes tested could be safely marketed.

A three-phase liquid phase microextraction (LPME) technique with high selectivity for five aromatic carboxylic acids and three phenolic compounds has been developed and optimized. The system consists of an acidified donor phase, a thin layer of solvent inside the wall pores of a hollow fiber, and an alkaline acceptor phase located inside the hollow fiber. The analysis of the compounds in the acceptor phase was carried out by capillary electrophoresis with UV detection. Eugenol, thymol, and carvacrol were efficiently extracted from the aqueous solution using chloropentane as organic phase, with recoveries from 73.8% to 93.8%. However, using 2-octanone as the organic phase, the recoveries for the aromatic carboxylic acid compounds ranged from 60.7% to 93.7% whereas the phenols were not extracted. 2,6-naphthalene-dicarboxylic acid was found to remain in the organic phase. The influence of 10% ethanol and 3% acetic acid in the donor phase was deeply studied as these solutions are commonly used as food simulants. AS4 silicone oil was found to be the best organic phase for the extraction of phenols both in 3% acetic acid and matrices with a high content of alcohol. The results obtained are shown and discussed.

An experimental laboratory-made assembly to determine for the first time the antioxidant capacity with respect to hydroxyl (OH*) radicals of several new active packagings directly in the materials has been developed. Gas-phase OH* radicals are generated by UV-light irradiation of an aqueous H(2)O(2) aerosol. After on-line reaction with up to eight parallel test samples, remaining OH* is quantitatively trapped by a salicylic acid solution, and antioxidant capacity is indirectly assessed by HPLC-fluorescence determination of the high sensitive 2,5-dihydroxybenzoic acid formed. Several natural essential oils as well as active plastic films including in their formulation such oils have been subjected to oxidation. Polymers containing clove and oregano were the most efficient ones (up to 7.2 and 4.7 times, respectively, more antioxidant than blanks), whereas rosemary, citronella and propolis showed average efficiency. On the other hand, active materials containing ferulic acid, quercetin, catechin and thymol, as well as commercial active bags with ethylene-absorption properties, showed limited or none antioxidant protection. Experimental results and full details about experimental assembly are given.

A two-phase based hollow fibre liquid-phase microextraction (HFLPME) with a high automatization degree and able to process up to six samples simultaneously by means of a multiple channel syringe pump has been successfully developed. The experimental set-up allows to carry out dynamic extractions with a considerable reduction of sample handling. The system has been applied for the first time to the determination in aqueous food simulant of migrants from prototypes of active packagings to assess their safety before marketing, showing detection limits in the ng g(-1) range, relative standard deviations below 13% and concentration factors ranging from 83 to 338.

Convenient methods that are capable of determining potentially antimicrobial compounds in both vapour and liquid phases are required (inter alia) to facilitate the development of active packaging materials using natural substances. The suitability of single-drop microextraction (SDME) coupled with gas chromatography-mass spectrometry (GC-MS) for this purpose has been assessed by evaluating its ability to determine a range of analytes (mainly terpenes) in vapour samples and three liquid food simulants - distilled water, 10% (v/v) water/ethanol, and 3% (w/v) acetic acid - by headspace-SDME (HS-SDME) and direct immersion-SDME (DI-SDME), respectively. In this contribution, a screening strategy based on the Hildebrand solubility parameter has been used to build a solvent priority list. Solvents were then tested following the list, taking into account additional factors such as low volatility for HS-SDME or buoyancy and relative miscibility for DI-SDME. Other experimental parameters affecting the performance of SDME (such as drop volume, sampling time and temperature, drop position in the sample vial, sample vial size, stirring rate, filling rate and ionic strength of the sample) were investigated using a Plackett-Burman screening design. The method optimisation was completed by means of response surface modelling (RSM). The methods were validated by characterising relevant performance parameters including their robustness, linear range, accuracy (trueness and precision) and capability of detection as described by the International Organization for Standardization.

Two new generation polymeric resins, Bond Elut ENV (styrene-divinylbenzene) from Varian and LiChrolut EN (ethylvinylbenzene-divinylbenzene) from Merck, commonly used in liquid–solid-phase extraction (SPE) were evaluated as sorbents for gas-phase sampling followed by thermal desorption and compared to Tenax TA, a reference sorbent in this kind of applications. The three resins were tested against seven volatile organic compounds (VOCs): 1-octene, ethylbenzene, (p-, m-, o-)xylenes, styrene and 1,4-dichlorobenzene. Elution curves for all compounds were determined at temperatures from 120 to 180 °C, and from such curves, different parameters, such as retention factor (k), distribution coefficient (K), height equivalent to a theoretical plate (H), asymmetry factor (Fa) and breakthrough volume (VB) were calculated and extrapolated at room (25 °C) and desorption (220 °C) temperatures in order to estimate breakthrough and elution volumes. In average, retention in LiChrolut EN is 10 and 200 times stronger than in Bond Elut ENV and Tenax TA, respectively, but its chromatographic behavior is rather poor giving quite asymmetric elution profiles (Fa > 1.8 at 120 °C). Bond Elut ENV exhibited the best chromatographic behavior, with H values two or five times lower than those of LiChrolut EN or Tenax TA. An additional advantage of the new sorbents is that retention decreases with T much faster than it does in Tenax (8 or 20 times for Bond Elut ENV or LiChrolut EN). Modeling has finally shown that beds with 60–80 (for Bond Elut ENV) or 300–400 (for LiChrolut EN) times less of sorbent have the same retention properties than standard Tenax TA tubes and similar (LiChrolut EN) or five to six times smaller (Bond Elut ENV) elution volumes. These predictions have been experimentally confirmed.

A solid-phase microextraction (SPME) method has been developed for the determination of pentachlorophenol (PCP) in paper and board samples. The analytical procedure involves direct extraction of PCP from paper and board samples and determination by gas chromatography with electron capture detection (GC-ECD). Two kinds of commercially available fibres; 100 microm polydimethylsiloxane (PDMS), apolar, and 85 microm polyacrylate (PA), quite polar, were evaluated to determine the extraction efficiency of pentachlorophenol. Parameters affecting the extraction process, such as temperature and time, were studied. Moreover, time of desorption and the effect of addition of salt were also investigated. The optimized procedure was applied to the analysis of pentachlorophenol (PCP) in five samples of virgin and recycled paper and board. The PCP content was determined by GC-ECD. To evaluate the effectiveness of the proposed method, it was compared with conventional extraction method with liquid-liquid extraction and derivatization. Detection limit of 0.015 microg/g for PCP in paper was achieved with a RSD of 14%.

Two low-volume solvent continuous extraction methods are applied to the extraction of paper matrices. In the methods reported here, a complex mixture of fluorescent whitening agents (FWAs) and azo dyes (AZOs) used in paper materials intended to come into contact with foodstuffs was extracted by using subcritical water extraction (SWE) and dynamic sonication-assisted solvent extraction (DSASE). Rationale for the work is based upon migration concerns of these groups of analytes from the packaging to the packaged items, thus compromising their subjective and/or objective quality. In SWE, sample was extracted in 21 min with 0.5 mL of water, whereas the DSASE method required 11 min and used 7 mL of water. DSASE was further developed by incorporating an organic modifier in order to change water polarity, thus improving extraction of moderately polar analytes. This way, modified-DSASE used a total organic volume of 0.9 mL which represents a reduction of 200 times in organic solvent consumption (200 mL versus approximately 1.0 mL) and 11 times in extraction time (2 h versus 11 min) compared to the existing methods. SWE was able to extract only 9 out of 12 test analytes with average recoveries between 10 and 25% whereas modified-DSASE succeed in extracting all the target analytes with an average recovery of 89%. Complete discussion and explanation concerning these differences are provided in the text.

A fast and simple method, using static single-drop microextraction (SDME), has been developed to facilitate the identification and quantification of seven dialkyl phthalate esters in the three aqueous food simulants. The simulants were: A, distilled water; B, 3% (w/v) acetic acid/water; and C, 15% (v/v) ethanol/water. The extraction is performed by simply suspending a drop of organic solvent in the aqueous sample using a conventional gas chromatography (GC) microsyringe. Following extraction, the organic phase is withdrawn into the syringe and analyzed by gas chromatography and flame ionization detection (FID). The optimized method yields a linear calibration curve over three orders of magnitude for all the simulants, and method detection limits (MDLs) allowing detection of all the studied compounds at concentrations below migration limits established by the European Union. The accuracy of the SDME method was tested and compared to that of solid-phase microextraction (SPME) by recovery experiments using spiked samples, with results ranging from 85 to 115% in most cases.

A new method has been developed to simultaneously analyse bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) in aqueous based food simulants. The method consists on direct immersion solid-phase microextraction (SPME) of the analytes from the liquid matrix and subsequent chromatographic analysis by gas chromatography-mass spectrometry. Using the proposed method, a whole analysis (including chromatographic step) can be completed in less than 40 min, with minimum sample handling. The SPME method shows good analytical performance for simultaneous BPA and BADGE analysis, except for BADGE determination in the aqueous alcohol (simulant C) solution. Detection limits ranging from 0.1 to 2.0 ng/g for BPA and from 13 to 15 ng/g from BADGE were obtained, with a linear range from the low-ng/g to several-microg/g range for BPA and from 0.1 microg/g to 40 microg/g for BADGE. A possible optimisation method has been also developed and introduced.

The optimization of supercritical fluid extraction of several organochlorine and organophosphorus pesticides is presented. The optimized method is compared with the classical sonication coupled to gel permeation chromatography as a clean-up method. The SFE method has been tested for 11 pesticides in spiked strawberries. At a spiking level of 100 ng/g, the pesticide recoveries were higher than 80%. The influence of the water content present in the sample is discussed. Two different approaches to solve this problem, which involve the use of anhydrous sodium sulfate mixed with the sample and alternatively the lyophilization, are presented too.

A procedure consisting of connecting in series two different HPLC columns, one for size-exclusion chromatography (SEC) and the second one a normal-phase (silica) column has been developed. An automatic three-way switching valve was placed between the two columns. Through the valve, the polymer was drained whereas the rest of the compounds, a group of antioxidants and UV stabilizers, were separated and analyzed in the second column. The behaviour of the SEC column in different organic phases is studied. Detection limits about 0.1 μg ml −1 were obtained for BHT, Tinuvin 326 and Tinuvin 327; 0.2 μg ml −1 for Irganox 1076, and 1.1 μg ml −1 for Cyasorb UV 9 and Cyasorb UV 1084. R.S.D. values of the whole process are lower than 4%.

A critical study was made of the standard addition procedure as applied in gas chromatography. The general procedure when an electron-capture detector is used in gas chromatography is discussed with the example of the determination of organochlorine compounds in a certified reference material of animal diet.