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An accurate quantification of phenolic compounds present in several kind of craft beers, corresponding worts, ingredients and spent products was performed by LC-MS/MS in this study. The dilution 1:2 of the sample with the mobile phase gave the best results, offering a very fast and simple method to reduce the matrix effect. A validated method was applied to six different types of craft beers, their worts, starting and spent products, such as barley malts and barley husks, starting hops and spent hops, and finally, starting yeast and spent yeasts to quantify the selected phenolic compounds. The Total Phenol Content (TPC) of barley malts is not negligible and it results almost prevalently due to trans-p-coumaric acid, which ranges from 76.4 μg/Kg for Mais to 672.6 μg/Kg for Munich. The trans-p-coumaric acid is transferred to the worts during the must preparation and is responsible for the not negligible TPC of worts, that was between 131.1 μg/Kg for Ego to 2041.6 μg/Kg for Alter beer. Bitter acids and prenylflavonoids are mainly present in the starting hops (TPC 323.8 μg/Kg and TPC 500.3 for Saaz and Perle hops, respectively). Their concentration strongly decreases in the spent hops where the TPC ranges between 8.0 μg/Kg for Triplo Malto to 24.4 μg/Kg for Alter, suggesting that they are transferred to the intermediate of production. Phenolic compounds, originally present in the starting barley malts and hops, are limitedly present into the final beers, and their TPC ranges approximately from 65.6 μg/Kg for Fiat lux to 105.3 μg/Kg for Alter. Actually, most phenolic compounds are absorbed into the yeast added for the fermentation, as it is clearly evident from the observation that spent yeasts contain a higher phenolic compounds amount with the respect to the starting yeast, and several phenolic compounds, in particular those coming from hops, are originally absent into the yeast and are only present in the spent ones., Competing Interests: Declaration of Competing Interest Authors declare no conflict of interest. They also declare that the work described has not been published previously (except in the form of an abstract, a published lecture or academic thesis), that it is not under consideration for publication elsewhere, that its publication is approved by all authors and tacitly or explicitly by the responsible authorities where the work was carried out, and that, if accepted, it will not be published elsewhere in the same form, in English or in any other language, including electronically without the written consent of the copyright-holder., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In order to assess if an extra virgin olive oil (EVOO) can be acknowledged with the health claim related to olive oil polyphenols (Reg. EU n.432/2012), a new method to quantify these species in EVOO, by means of liquid-liquid extraction followed by HPLC-DAD/MS/MS of the hydroalcoholic extract, has been developed and validated. Different extraction procedures, different types of reverse-phase analytical columns (Synergi Polar, Spherisorb ODS2 and Kinetex) and eluents have been tested. The chromatographic column Synergi Polar (250×4.6mm, 4μm), never used before in this kind of application, provided the best results, with water and methanol/isopropanol (9/1) as eluents. The method allows the quantification of the phenolic alcohols tyrosol and hydroxytyrosol, the phenolic acids vanillic, p-coumaric and ferulic acids, secoiridoids derivatives, the lignans, pinoresinol and acetoxypinoresinol and the flavonoids luteolin and apigenin. The new method has been applied to 20 commercial EVOOs belonging to two different price range categories (3.78-5.80 euros/L and 9.5-25.80 euros/L) and 5 olive oils. The obtained results highlight that acetoxypinoresinol, ferulic acid, vanillic acid and the total non secoiridoid phenolic substances resulted to be significantly higher in HEVOOs than in LEVOOs (P=0.0026, 0.0217, 0.0092, 0.0003 respectively). For most of the samples analysed there is excellent agreement between the results obtained by applying the HPLC method adopted by the International Olive Council and the results obtained by applying the presented HPLC method. Results obtained by HPLC methods have been also compared with the ones obtained by the colorimetric Folin-Ciocalteu method., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this work, we present for the first time a rapid and robust UHPLC-MS/MS method for analyzing taurine, GlcLA and GlcA in energy drinks simultaneously and without derivatization. The separation of three analytes was achieved using a Kinetex Hilic analytical column (100 mm × 4.6 mm i.d.) and a mobile phase formed by water (A) and acetonitrile (B) both with formic acid 0.1% at a flow rate of 0.8 ml min(-1) with isocratic elution in 3.5 min. Calibration curves were calculated using the method of standard addition in a concentration range from 2 to 6 mg/100 ml for taurine (R(2)>0.987), from 0.4 to 1.2 mg/100 ml for GlcLa (R(2)>0.997), and from 0.2 to 0.6 mg/100 ml for GlcA acid (R(2)>0.998). The validated method was applied to the analysis of nine commercial energy drinks. The level of taurine found ranged from 0.01 to 0.45 g/100 ml, and it matched with that reported in the labels of the analyzed energy drink samples., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A new analytical method that uses high performance liquid chromatography-diode array detector (HPLC-DAD) was developed for the analysis of 14 benzimidazoles residues, including metabolites, in bovine liver. Samples were extracted using two different extraction procedures: with phosphate buffer after enzymatic hydrolysis (method A) or using organic solvent, i.e. acetonitrile (method B). Then, samples were purified on a strong cation exchange (SCX) cartridge and analyzed in HPLC/DAD. The recovery percentages, obtained spiking the matrix (liver) at concentrations of 500 and 100 microg kg(-1) with a standard mixture of benzimidazoles, were in the range 6-101% and 80-102% for methods A and B, respectively. The repeatability of the methods was assessed in all cases by the % of correlation value (CV) that was lower than 19%. The limits of quantification (LOQs) in the matrix for methods A and B were in the range 40-60 and 20-50 microg kg(-1), respectively. The best of the two methods, method B, was used for the analysis of 10 bovine liver samples., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

A new analytical method, using gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-mass spectrometry (LC/MS) techniques, was developed for the determination in packaged food beverages of five ink photoinitiator residues: 2-isopropylthioxanthone (ITX), benzophenone, 2-ethylhexyl-4-dimethylaminobenzoate (EHDAB), 1-hydroxycyclohexyl-1-phenyl ketone (IRGACURE 184) and ethyl-4-dimethylaminobenzoate (EDAB). Samples were extracted from selected beverages (milk, fruit juices and wine) and relative packagings, using n-hexane and dichloromethane, respectively, purified on solid-phase extraction (SPE) silica gel cartridges, and then analyzed in GC/MS and LC/MS. The recovery percentages, obtained spiking the beverage samples at concentrations of 4 and 10 microgl(-1) with a standard mixture of photoinitiators, were in the range 42-108% (milk), 50-84% (wine), and 48-109% (fruit juices). The repeatability of the method was assessed in all cases by the % of correlation value, that was lower than 19%. The lowest limits of detection (LODs) and limits of quantification (LOQs), obtained using GC/MS, were in the range 0.2-1 and 1-5 microgl(-1), respectively. The method was applied to the analysis of forty packaged food beverages (milk, fruit juices and wine samples). The most significant contamination was that of benzophenone, found in all samples in a concentration range of 5-217mugl(-1). Its presence was confirmed by an LC/Atmospheric-Pressure PhotoIonization (APPI)/MS/MS analysis. The photoinitiator (EHDAB) was found in eleven out of forty beverages in a concentration range of 0.13-0.8 microgl(-1). Less important was the ITX contamination, found in three out of forty samples in a range 0.2-0.24 microgl(-1). The work proposes a new method to analyze ink photoinitiator residues in polycoupled carton packaging and in contained food beverages.

A new analysis method to detect carbamates and phenylurea pesticide residues in fruit juices was developed using solid-phase microextraction (SPME) coupled with liquid chromatography-single quadrupole mass spectrometry (LC/MS) and liquid chromatography-quadrupole ion trap mass spectrometry (LC/QIT-MS). The pesticide residues present in watery matrices as fruit juices were extracted using three types of fibers: 50-microm Carbowax/templated resin (CW/TPR), 60-mum poly(dimethylsiloxane)/divinylbenzene (PDMS/DVB) and 85-microm polyacrylate. The different extraction conditions were evaluated choosing as the best parameters 90 min (time), 20 degrees C (temperature) and 1 ml (volume). After extraction, the desorption (in a static mode) was performed in the specific interface chamber SPME/HPLC, previously filled with 70% methanol and 30% water. The best recoveries, evaluated at two fortification levels (0.2 and 0.5 mg kg(-1)) in fruit juices, were obtained using PDMS/DVB and CW/TPR fibers, and ranged from 25 to 82% (monolinuron, diuron and diethofencarb), with relative standard deviations (RSDs) from 1 to 17%. All the limits of quantification (LOQs) were in the range of 0.005-0.05 microg ml(-1) and, in any case, equal to, or lower than, maximum residue limits (MRLs) established by Italian and Spanish legislations. The mass spectrometry analyses were carried out using an electrospray ionization (ESI) source operating in the positive mode both for single quadrupole and for QIT mass analysers, operating in selected ion monitoring (SIM) and in multiple reaction monitoring (MRM) modes, respectively. The proposed new method can be applied to the determination of selected pesticides in real samples of fruit juices.