Oligomers: Hidden sources of bisphenol A from reusable food contact materials.

A recent European Regulation further restricted the use of bisphenol A in food-contact materials, reducing its limit of migration. However, all analytical systems of control are aimed at identifying and quantifying the molecules of this monomer without taking in consideration the possible presence of its oligomers, species originating from material degradation and able to follow an in-vivo hydrolysis providing bisphenol A generation. Thus, the presence of oligomers of polycarbonate deriving by unreacted species or polymer degradation can be considered a hidden source of several bisphenol A units, that remains outside the control of legislation and should be considered of high concern. This work was focused on the identification and the description of kinetics of release of different molecules migrating from polycarbonate food contact materials to simulants and to a model food sample such as melted chocolate. Analyses were performed by UHPLC system coupled to a Q-Exactive mass spectrometer. Targeted and untargeted analysis through data dependent acquisition mode allowed to detect the occurrence of several species deriving from polycarbonate, and permitted to investigate the polymer degradation pattern and explore the correlation of the recorded amounts of each product with age, hours of usage, and washing cycles of the plastic items.

Optimization of mass spectrometry acquisition parameters for determination of polycarbonate additives, degradation products, and colorants migrating from food contact materials to chocolate.

The interest towards "substances of emerging concerns" referred to objects intended to come into contact with food is recently growing. Such substances can be found in traces in simulants and in food products put in contact with plastic materials. In this context, it is important to set up analytical systems characterized by high sensitivity and to improve detection parameters to enhance signals. This work was aimed at optimizing a method based on UHPLC coupled to high resolution mass spectrometry to quantify the most common plastic additives, and able to detect the presence of polymers degradation products and coloring agents migrating from plastic re-usable containers. The optimization of mass spectrometric parameter settings for quantitative analysis of additives has been achieved by a chemometric approach, using a full factorial and d-optimal experimental designs, allowing to evaluate possible interactions between the investigated parameters. Results showed that the optimized method was characterized by improved features in terms of sensitivity respect to existing methods and was successfully applied to the analysis of a complex model food system such as chocolate put in contact with 14 polycarbonate tableware samples. A new procedure for sample pre-treatment was carried out and validated, showing high reliability. Results reported, for the first time, the presence of several molecules migrating to chocolate, in particular belonging to plastic additives, such Cyasorb UV5411, Tinuvin 234, Uvitex OB, and oligomers, whose amount was found to be correlated to age and degree of damage of the containers.

UHPLC-high-resolution mass spectrometry determination of bisphenol A and plastic additives released by polycarbonate tableware: influence of ageing and surface damage.

A new UHPLC-ESI-Orbitrap method for the identification and the quantitative determination of bisphenol A and some common additives employed in plastic manufacturing has been developed and validated. The method has been applied to evaluate the migration from 14 samples of tableware of different age and degree of surface damage, in both ethanol and isooctane (used as food simulants according to EU plastic regulation). Bisphenol A, three UV light absorbers, and one whitening agent were detected and quantified. Data were analyzed with the aim of exploring a possible correlation between bisphenol A and additives release, ageing, and surface integrity. A high correlation between age of samples, surface damage, and bisphenol A migration has been evaluated, while the release of additives was not correlated with other parameters. Obtained data showed for the first time that the release of bisphenol A seems to be more connected to ageing than to scratches and cracks occurrence. Graphical Abstract Bisphenol A and additives released by polycarbonate tableware: influence of ageing and surface damage.

Targeted and untargeted data-dependent experiments for characterization of polycarbonate food-contact plastics by ultra high performance chromatography coupled to quadrupole orbitrap tandem mass spectrometry.

Materials that come in contact with foods are potential sources of chemical food contamination. Consequently, characterization of their composition is of paramount importance considering the possible occurrence of several unknown molecules such as non-intentionally added substance (NIAS), residual monomers, degradation products, plastic additives and organic colorants. Previous studies concerning the characterization in terms of composition are focalized in the recognition of additives. To the best author's knowledge there are no scientific data about the composition of a plastic material in terms of colorants. In this work, an analytical method employing capillary ultra high-performance liquid chromatography and electrospray ionization quadrupole orbitrap high-resolution mass spectrometry (UHPLC-ESI Q-orbitrap) was exploited for characterization of polycarbonate for food contact material. Data-dependent experiments for targeted and untargeted analysis were employed after a total dissolution of polycarbonate samples and extraction of its components. The presence of common additives such as antioxidants and UV absorbers was confirmed by targeted analysis, while, the untargeted approach combined with the high mass accuracy of orbitrap technology allowed to identify for the first time some polycarbonate degradation products and the organic dyes effectively used for the coloration of plastic objects intended to come in contact with food. The present study shows the high potential of this technique in the field of material characterization aimed at food safety evaluation.

High-performance liquid chromatographic phenolic compound fingerprint for authenticity assessment of honey.

BACKGROUND: Phenolic compound profiles of 20 honeys of different botanical origin (eucalyptus, citrus, chestnut and linden) were obtained by high-performance liquid chromatography with ultraviolet detection after solid phase extraction, in order to evaluate the effectiveness of the fingerprint method for monofloral honey discrimination. RESULTS: A total of 58 peaks were detected at λ = 280 nm. Distinctive phenolic compound profiles were obtained in which both the nature and the relative amount of the detected compounds were characteristic for different botanical source honeys. In order to detect sample groupings, chromatographic peak areas were submitted to principal component analysis. Then linear discriminant analysis was carried out on the first three principal components. In addition, linear discriminant analysis was carried out on the 58 variables, allowing the selection of five variables able to discriminate honeys of different botanical origin. CONCLUSION: The chemometric evaluation of the phenolic compound profiles yielded classification models able to group honey samples according to their floral source with an excellent degree of agreement. The main advantage of the fingerprint approach with respect to traditional methods is that it does not require time-consuming identification and quantification of the analytes. The method proved to be effective for the assessment of honey authenticity.

Sterol oxidation in meat- and fish-based homogenized baby foods containing vegetable oils.

Sterol oxidation was evaluated in commercial meat- and fish-based homogenized baby foods containing vegetable oil. Gas chromatography coupled with mass spectrometry (GC/MS) was used for the analytical determination of 7-ketocholesterol and 7-ketositosterol, which were chosen as markers of sterol oxidation in lipids of animal origin and vegetable origin, respectively. Cholestanetriol was also quantified, because its negative effects on atherogenesis and other biological processes are well known. In meat-based samples, the levels of 7-ketocholesterol and 7-ketositosterol were 22-89 and 11-40 microg/serving, respectively, whereas the cholestanetriol levels were 7-38 microg/serving. The 7-ketocholesterol/cholesterol percent ratio was characteristic of each kind of meat and related to the levels of unsaturated fatty acids of animal lipids. In fish-based samples, the cholestanetriol and 7-ketocholesterol levels per serving were significantly lower than in meat samples, but in fish fillets they were about 20-25%, instead of 40%, of the ingredients. The values of the 7-ketocholesterol/cholesterol percent ratio in fish-based products were close to the values computed for chicken or turkey-based products. The detected values of cholestanetriol showed that the addition of vegetable oil enhances the development of the indirect bimolecular pathway of cholesterol oxidation, which was even more favorable in fish-based products.

Geographical traceability of West Liguria extravirgin olive oils by the analysis of volatile terpenoid hydrocarbons.

This study aimed at evaluating if the volatile terpenoid hydrocarbons of extravirgin olive oils from West Liguria, a North Italy region, could trace their geographical origin. If terpenoid hydrocarbons were individually considered, three compounds, i.e. alpha-copaene, alpha-muurolene and alpha-farnesene, allowed building a simple decision tree and discriminating oils produced in West Liguria from oils produced in other Mediterranean regions. Moreover, the multivariate analysis allowed building West Liguria class-models with high predictive ability, confirming the fundamental role of the volatile terpenoid hydrocarbons for the geographical characterisation of West Liguria oils.