Determination of phthalic acid esters and di(2-ethylhexyl) adipate in coffee obtained from capsules.

In this work, the ammonium formate version of the QuEChERS method has been applied for the first time to the extraction of a group of nine phthalic acid esters and one adipate from three types of coffee (maximum intensity, intermediate intensity and decaffeinated) prepared from coffee capsules, using gas chromatography coupled to mass spectrometry for analytes separation and determination. Matrix-matched calibration showed good linearity with determination coefficients (R2) higher than 0.9983 for all analytes and matrices. In general, matrix effect assessment revealed a medium effect of signal suppression, while mean relative recovery values were in the range 70-120% with relative standard deviation values ≤19% for most analytes. Several samples of each type of coffee obtained from capsules made of different materials were also analysed, finding concentrations of DBP, DEHA and DEHP in the range 29.3-734 ng/capsule, below the tolerable daily intake established for some of them.

Determination of pesticides in dried minor tropical fruits from Colombia using the Quick, Easy, Cheap, Effective, Rugged, and Safe method-gas chromatography-tandem mass spectrometry.

The AOAC 2007.1 quick, easy, cheap, effective, rugged, and safe official method, together with gas chromatography coupled to a triple quadrupole mass spectrometer was applied for the analysis of 38 multiclass pesticides from dried fruits typically cultivated and exported from Colombia: uchuva (Physalis peruviana), lulo (Solanum quitoense), guanabana (Anona muricata), and pitahaya (Hylocereus undatus). The whole method was validated in terms of matrix-matched calibration, matrix effect, and recovery using atrazine-d5 as internal standard, triphenylphosphate for quality control of the injection, and a proper mixture of analytes protectants. Matrix-matched calibration data were found satisfactory for all pesticides and dried fruits, reporting R2 values above 0.99. Matrix effect values evidenced the existence of such effect in most cases. The applied procedure gave satisfactory recovery percentages (70-120%) and relative standard deviation values (< 20%) for 92% of the 456 combinations pesticide/fruit studied (spiked levels of 25, 200, and 400 µg/kg). Finally, 20 real dried fruit samples were analyzed and residues of tebuconazole were found in two samples of uchuva at a concentration below the lowest calibration level of the method for one of them and at 10.8 ± 1.6 µg/kg for the other, being below or similar to the general maximum residue level established for monitoring purposes in food applications.