Beef quality grading using rapid evaporative ionization mass spectrometry (REIMS)

The Rapid evaporative ionization mass spectrometry (REIMS) technique enables real-time metabolite analysis of intact beef tissues, potentially predicting carcass traits and quality. Two 10-day aged muscles from 66 Limousine cows of a specific production system, rump ( m. gluteus medius , RMP, n = 63) and striploin ( m. longissimus thoracis , STR, n = 57) were measured using REIMS. The REIMS outputs were used to develop classification and prediction models via orthogonal partial to latent structures-discriminant (OPLS-DA). Variables studied included carcass traits (transport distance, muscle type, EUROP conformation, carcass weight, Meat Standards Australia (MSA) marbling score), laboratory measurements (intramuscular fat (IMF) content, Warner-Bratzler shear force (WBSF), compression force), and sensory traits (untrained consumer scores and the calculated meat-eating quality score (MQ4)). Variables were divided into two binary groups based on median values. The REIMS accurately distinguished RMP from STR muscles (test accuracy = 100%), and showed strong associations with transport distance, carcass traits, and laboratory measurements (R 2 Y = 0.86–0.94; Q 2 = 0.55–0.78; test accuracy = 41.7%–66.7%). For sensory quality traits, RMP-based models achieved test accuracies of 63.3%–73.3%, while STR-based models failed to reliably predict any traits (test accuracies