Migration of dihydroxyalkylamines from polypropylene coffee capsules to Tenax® and coffee by salt-assisted liquid-liquid extraction and liquid chromatography-mass spectrometry.

Migration of N,N-Bis(2-hydroxyethyl) alkyl(C8-C18)amines from five different polypropylene capsules to Tenax® and coffee powder have been studied. A single step extraction-cleanup procedure using salting out liquid-liquid extraction (SALLE) method followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was applied. The critical parameters on the SALLE procedure such as extracting solvent, extracting volume, sample pH, salt and its concentration were optimized. The recovery values were in the range of 87.5%-106.5%. The %RSD were lower than 3.7%. The limit of detection was improved from 2.3 ng/g in Tenax® to 0.8 ng/g in coffee. The results indicated that the analyzed compounds have the potential to migrate from the polypropylene capsule containers to the coffee. In most of the cases, the migrated values were higher in Tenax® than in coffee in a range between 1.8 and 61%. One sample did not comply with the specific migration limit established by the European Commission.