Microchemical Techniques for Multiclass Fungicide Residue Analysis in Complex Food Matrices

Fungicide residues in complex food matrices represent an increasingly important challenge in food safety monitoring because intensive agricultural practices, diverse fungicide chemistries, and tropical production conditions can generate multiclass contamination patterns, particularly in Southeast Asian food systems. This review critically evaluates literature published between 2019 and 2026 on microchemical analytical strategies for multiclass fungicide residue determination in fruits, vegetables, rice, spices, and processed foods. The review focuses on the integration of miniaturized and green sample preparation techniques, including modified QuEChERS, dispersive liquid–liquid microextraction, solid-phase microextraction, hollow-fiber liquid-phase microextraction, magnetic solid-phase extraction, and deep eutectic solvent-based extraction, with advanced chromatographic and mass spectrometric platforms. Current evidence shows that these methods can reduce solvent consumption, improve analytical efficiency, and support sensitive residue determination when coupled with UHPLC–MS/MS, GC–MS/MS, and high-resolution mass spectrometry. However, method performance remains strongly matrix-dependent and is constrained by matrix effects, limited standardization of emerging extraction materials, inconsistent validation practices, and trade-offs among selectivity, throughput, cost, and sustainability. No single extraction strategy is universally optimal for all food matrices or fungicide classes. Future research should therefore prioritize matrix-adapted hybrid workflows, harmonized validation protocols, improved detection of transformation products, and broader use of high-resolution screening strategies to support reliable, sustainable, and regulatory-compliant fungicide residue monitoring.