Straightforward sample preparation method for the analysis of pesticide residues in ginger (Zingiber officinale Rosc.) using gas chromatography-tandem mass spectrometry

•Medicinal plants & species are polyphenol rich and difficult matrices for residue analysis.•An aluminium sulphate-based protocol for residue analysis in ginger was developed.•The method yielded better results than traditional QuEChERS protocols.•Polyphenol coextraction is minimized by forming Aluminium complexes.•Maintenance and sensitivity of the gas chromatographic system are improved.