Novel Ion Suppression-Based MS Approach (IS-MS) for Straightforward, Robust, and Rapid Identification and/or Differentiation of Liquid Samples: Wine as a Case Study

A rapid and robust mass spectrometric approach based on ion suppression effects was developed for the identification and authentication of liquid food samples. Wine was used as a model system to evaluate sample discrimination according to vintage, country of origin, producer and name. A defined mixture of 25 chemical marker compounds was added to each sample, followed by dilution and direct analysis using electrospray ionization mass spectrometry (ESI-MS) operated in selected ion monitoring (SIM) mode. Sample-specific matrix effects on the ionization efficiencies of the marker compounds produced characteristic mass spectral response patterns, which were acquired within approximately 1 min per sample. These patterns were compared with reference data derived from a comprehensive wine database. Multivariate statistical analysis was performed using linear discriminant analysis (LDA) combined with complementary distance-based metrics. The approach was validated using five vintages of several premium wines. High authentication scores were obtained for all samples, demonstrating the suitability of the approach for rapid wine authentication and verification of origin. The results indicate that ion suppression-based MS fingerprinting represents a promising tool for fast, minimal-preparation assessment of authenticity in food analysis.