Rafael Paseiro-Cerrato

Migration of Photoinitiators by Gas Phase into Dry Foods

Photoinitiators are components widely used in UV-cured inks for printing food packaging. In the present study, the migration of seven photoinitiators through the vapor phase was investigated. To perform the migration test, an additive enriched polyethylene wax was used as a source to release photoinitiators. The method was applied to evaluate the migration of the photoinitiators into five selected dry foods (cake, bread, cereals, rice and pasta). The highest level of migration was found in the cake. Parameters affecting the migration process were evaluated, and high migration level was found to correlate with both the porosity and the fat content. In addition, the kinetics of migration of the photoinitiators from the additive enriched wax into the cake were studied under accelerated conditions.

Rapid multi-analyte quantification of benzophenone, 4-methylbenzophenone and related derivatives from paperboard food packaging

Photo-initiators are used in printing inks hardened with UV light and one of the most commonly used photo-initiators is benzophenone (BP). Recent notifications under the Rapid Alert System for Food and Feed have shown migration of 4-methylbenzophenone (4-MBP) from packaging into cereals. A specific migration limit exists for BP of 0.6 mg kg−1 for its use as an additive in plastics. There is no specific European legislation covering cardboard boxes and/or printing inks for food contact use. However, due to the high levels detected, the European Food Safety Authority (EFSA) published recommendations and the Standing Committee for the Food Chain and Animal Health endorsed a limit of 0.6 mg kg−1 for the sum of BP and 4-MBP. While studies have been published on photo-initiators in the past, there is a fundamental lack of data on 4-MBP especially for its combined analysis with others. We present an HPLC method with diode array detector to simultaneously determine the levels of BP, 4-MBP as well as 7 other possible derivatives from secondary packaging for food applications. The method was tested and applied to 46 samples of paperboard for secondary packaging collected both from supermarkets and directly from a paperboard supplier. In addition, a survey was conducted on recycled paperboard (n = 19) collected from a supplier, to evaluate the background quantity of BP and other derivatives in recycled board. The most abundant photo-initiator found in the survey was BP, in 61% of samples, and 4-MBP was found in 30% of the samples. It seems that these compounds are used to replace one another. Other derivatives were found in minor quantities. Traces of BP were also found in 42% of the samples of recycled, unprinted board.

Evaluation of Long-Term Migration Testing from Can Coatings into Food Simulants: Polyester Coatings

FDA guidance for food contact substances recommends that for food packaging intended for use at sterilized, high temperature processed, or retorted conditions, a migration test with a retort step at 121 °C for 2 h followed by a 10 day migration test at 40 °C should be performed. These conditions are in intended to simulate processing and long-term storage. However, can coatings may be in contact with food for years, and there are very few data evaluating if this short-term testing accurately simulates migration over extended time periods. A long-term migration test at 40 °C with retorted and non-retorted polyester cans using several food simulants (water, 3% acetic acid, 10% ethanol, 50% ethanol, and isooctane) was conducted to verify whether traditional migration testing protocols accurately predict migration from food contact materials used for extended time periods. Time points were from 1 day to 515 days. HPLC-MS/MS was used to analyze polyester monomers, and oligomer migration was monitored using HPLC-DAD/CAD and HPLC-MS. Concentrations of monomers and oligomers increased during the migration experiments, especially in ethanol food simulants. The data suggest that current FDA migration protocols may need to be modified to address changes in migrants as a result of long-term storage conditions.

Development of a rapid screening method to determine primary aromatic amines in kitchen utensils using direct analysis in real time mass spectrometry (DART-MS)

Primary aromatic amines (PAAs) are a group of substances with undesirable health effects, that are used in a variety of commercial products. Several recent studies, using a number of screening and confirmatory methods, have reported the migration of PAAs from some kitchen utensils into acetic acid 3% (w/v). Many of these methods require significant sample preparation, therefore the aim of this work was to determine if direct analysis in real time mass spectrometry (DART-MS) could be utilised as a rapid screening tool for the determination of PAAs in kitchen utensils. DART-MS results from direct analysis of the utensil have been compared with results of PAA migration by ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. The UPLC-MS/MS method had excellent linearity, appropriate sensitivity (LOD ≤ 1.5 µg L−1; LOQ ≤ 4.5 µg L−1), repeatability from 2.4 to 13.2% and acceptable recoveries. DART-MS results were in good agreement with UPLC-MS/MS data, with 100% of non-compliant (PAA positive) samples successfully identified by DART-MS.

Analytical method for the simultaneous determination of polyfunctional amines used as monomers in the manufacture of food packaging materials.

This paper describes the development of a multi-analyte method for the determination of polyfunctional amines commonly used as monomers in the manufacture of food contact materials. Amines were analyzed by high-performance-liquid chromatography with diode-array detection (HPLC-DAD) after derivatization with dansyl chloride. The chromatographic analysis and the derivatization conditions were optimized. The proposed method was validated in terms of linearity, limits of detection and repeatabilities. The method showed an excellent sensitivity (LOD≤0.05 μg/mL) and appropriate repeatabilites (RSD (n=7)≤5%)). LC-MS/MS was used as a confirmatory technique. The stability of the amines in five food simulants (distilled water, 3% acetic acid, 10% ethanol, 50% ethanol and olive oil) under the most common testing conditions (10 days at 40 °C) was also studied. Results showed that amines had an acceptable stability in aqueous simulants but in the olive oil a loss of 100% was observed for all analytes.

Study of the partition coefficients Kp/f of seven model migrants from LDPE polymer in contact with food simulants

ABSTRACT This study evaluated the influence of parameters such as temperature and type of low-density polyethylene (LDPE) film on the log Kp/f values of seven model migrants in food simulants. Two different types of LDPE films contaminated by extrusion and immersion were placed in contact with three food simulants including 20% ethanol, 50% ethanol and olive oil under several time–temperature conditions. Results suggest that most log Kp/f values are little affected by these parameters in this study. In addition, the relation between log Kp/f and log Po/w was established for each food simulant and regression lines, as well as correlation coefficients, were calculated. Correlations were compared with data from real foodstuffs. Data presented in this study could be valuable in assigning certain foods to particular food simulants as well as predicting the mass transfer of potential migrants into different types of food or food simulants, avoiding tedious and expensive laboratory analysis. The results could be especially useful for regulatory agencies as well as for the food industry.

Evaluation of Short-Term and Long-Term Migration Testing from Can Coatings into Food Simulants: Epoxy and Acrylic–Phenolic Coatings

Traditionally, migration testing during 10 days at 40 °C has been considered sufficient and appropriate for simulating the potential migration of substances from food-contact materials into foods. However, some packages, such as food cans, may be stored holding food for extended time periods (years). This study attempts to verify whether common testing conditions accurately estimate long-term migration. Two types of can coatings, epoxy and acrylic-phenolic, were subjected to short-term and long-term migration testing (1 day-1.5 years) using food simulants (water, 3% acetic acid, 50% ethanol, and isooctane) at 40 °C. Using HPLC-DAD/CAD, HPLC-MS, UHPLC-HRMS (where HRMS is accurate mass, mass spectrometry), and DART-HRMS, we identified potential migrants before starting the experiment: BPA, BADGE, BADGE derivatives, benzoguanamine, and other relevant marker compounds. During the experiment using a water-based food simulant, migrants remained stable. Most of the cans in contact with 3% acetic acid did not survive the experimental conditions. Tracked migrants were not detected in isooctane. In the presence of 50% ethanol, the traditional migration test during 10 days at 40 °C did not predict migration during long-term storage. These results suggest that migration protocols should be modified to account for long-term storage.

Instability of an aromatic amine in fatty food and fatty food simulant: characterisation of reaction products and prediction of their toxicity

It is a well-known fact that amines are not stable in food of a fatty nature. In this study the synthesis and characterisation of the products obtained as a result of the reaction of amines in a fatty medium are reported. Based on the well-known reactions among amines and acid and esters groups, two novel compounds were synthesised using m-xylylenediamine (mXDA), a primary diamine widely used as monomer in the manufacture of food contact materials and two fatty acids, oleic acid and palmitic acid, which occur in most fats. The resulting compounds were two molecules belonging to the family of fatty acid amides, dioleamide and dipalmitamide. A complete characterisation of both products was carried out employing several techniques such as infrared spectroscopy, 1H- and 13C-NMR spectroscopy, electron ionisation mass spectrometry, LC-MS/MS and UV spectrometry. The results obtained by the different techniques were well correlated. In the second part of the work, the formation of these compounds in real samples was evaluated. For this purpose a certain volume of olive oil was spiked with a known amount of mXDA. Olive oil was selected as a fatty medium since it is a widely consumed food and additionally is used as a fatty food simulant in migration studies of food contact materials. A method was developed to extract the fatty acid amides from the fatty matrix, which were then identified by LC-MS/MS. The toxicity of the synthesised compounds was predicted using a toxicity estimation software tool. Graphical Abstract

Determination of diffusion and partition coefficients of model migrants by direct contact and vapour phase transfer from low-density polyethylene films into cake

ABSTRACT The aim of the present study was to determine the migration kinetics of one photoinitiator, benzophenone, and two optical brighteners, Uvitex OB and 1,4-diphenyl-1,3-butadiene (DPBD), from low-density polyethylene (LDPE) films into cake. Transfer was assessed by both direct contact and also the vapour phase. To perform the migration tests by direct contact, plastic films enriched with the additives were placed between two cake slices. To evaluate the migration through the gas phase, cake and the fortified LDPE film were placed with no direct contact in a glass container that was hermetically closed. Samples were stored at different time–temperature conditions. Target compounds were extracted from the films with ethanol (70°C, 24 h) and analysed by HPLC-DAD. Relevant parameters such as partition and diffusion coefficients between food and plastic film were calculated. The Arrhenius equation was applied to estimate the diffusion coefficient at any temperature. The data indicate that migration of benzophenone occurs in a significant extent into cake by both direct contact and through the gas phase (no direct contact). Conversely, very little migration occurred for Uvitex OB by direct contact and none through the gas phase. Results for benzophenone suggest that migration through the gas phase should be considered when evaluating migration from food packaging materials into food. Graphical Abstract