Pesticide Detection in Food Products through Bead Mill Homogenization and QuEChERS Extraction

The QuEChERS method was introduced in 2003 for “Quick, Easy, Cheap, Effective, Rugged and Safe” extraction of multiple pesticides and has since been modified and optimized to support a wide range of analytes (1). The QuEChERS method is widely used and is formalized in two documented methods, AOAC 2007.01 and EN 156223. Prior to the QuEChERS extraction the sample must first be comminuted. The comminuting process can be performed in a number of ways including, manual chopping, blending and milling. A more recent approach has been to homogenize the plant material through bead beating, a process in which the plant material is placed in a sealed tube with beads and vigorously shaken to produce a final homogenate of sub micron particle sizes (2). The advantage of this approach is that the homogenization can be performed in a 50 mL centrifuge tube containing 15 g of plant material and 5 to 15 mL of acetonitrile which is the starting solvent for common QuEChERS extractions. 

Herein, we describe the application of bead mill homogenization and QuEChERS extraction for the detection of pesticides in food products. The 50 mL tube carriage for the Omni Bead Ruptor Elite™ bead mill homogenizer supports simultaneous homogenization of up to three samples in a standard 50 mL polypropylene centrifuge tube and provides sufficient force to homogenize even extremely tough samples.

Figure 2. Pesticides were extracted and analyzed by LC-MS/MS operated in MRM mode.