Analysis of Simultaneous Screening for 277 Pesticides in Malt and Beer by Liquid Chromatography with Tandem Mass Spectrometry

Simple and sensitive methods for the simultaneous analysis of pesticides in malt and beer were developed using liquid chromatography with tandem mass spectrometry (LC/MS/MS). The extraction from malt carried out with acetonitrile/water was followed by liquid-liquid extraction with ethyl acetate and was purified in a solid-phase cartridge. The extraction from beer was carried out with ethyl acetate and purified in the same solid-phase cartridge. The LC separation was performed with an octadecylated silica column (5 μm, 2.1 × 150 mm) with a flow rate of 0.2 mL/min using a mobile phase consisting of water and methanol including ammonium acetate. MS/MS was used in multiple reaction monitoring, employing electrospray ionization. Recovery of the 277 pesticides was between 79.5 and 120.3% from malt and between 45.0 and 114.4% from beer spiked at 0.02 mg/kg. The method was applied to the analysis of 10 malt samples. Twelve chemicals were detected, and all samples complied with the maximum residue limits for barley in Japan. This method may have applications in quality assurance.