Comparative Study of Hydrolysis-Based Methods Coupled with QuEChERS Extraction Followed by GC–MS/MS and LC–MS/MS for the Determination of Complex Pesticide Residues in Melons and Dry Beans

Determination of complex pesticide residues in food matrices poses a considerable analytical challenge, primarily because the analytes exhibit diverse physicochemical properties. Monitoring pesticides across a wide range is essential to meet all regulatory requirements and safeguard consumer health. One of the most promising analytical approaches is the hydrolysis of compounds, particularly acidic hydrolysis, which enables the identification of a broad range of substances that pose significant analytical challenges. In addition, pesticide residues may interact with food matrix components, leading to the formation of conjugated forms such as ester- or glycoside-bound compounds. Therefore, the development of appropriate analytical strategies, including hydrolytic steps, is essential to release these bound residues and enable the determination of complex residue definitions comprising multiple related compounds. Furthermore, this study compares different hydrolysis strategies, including enzymatic, acidic, and alkaline hydrolysis, in order to assess their suitability for the determination of complex pesticide residue definitions using a QuEChERS-based (Quick, Easy, Cheap, Effective, Rugged, Safe) extraction approach. The given methodology meets all criteria listed in the Document SANTE 11312/2021 v2026. The procedure allows for good measurement precision relative standard deviation (RSD < 20%), and recovery in the scope ranging from 55.6% to 107.8% acidic hydrolysis and 51.7% to 100.8% for alkaline hydrolysis and 35.1–108.9% for enzymatic hydrolysis depending on the experimental variant, and limit of quantification (LOQ) as low as 10 to 100 µg/kg for the determination of ten complex definitions of pesticides with the use of liquid chromatography mass spectrometry (LC-MS/MS) and gas chromatography mass spectrometry (GC-MS/MS) analytical methods.