Accurate lamb origin identification and molecular differentiation analysis using rapid evaporative ionization mass spectrometry†

Rapid and accurate methods for tracing and identifying the origin of lamb are crucial for ensuring food authenticity and quality. This study developed a precise traceability method to determine the origin of lamb by integrating rapid evaporative ionization mass spectrometry (REIMS) with multivariate statistical analysis. Lamb samples from Xilin Gol, Ordos, and Hulun Buir ranches were identified by REIMS fingerprinting within 1 min. The discrimination model based on lipid molecular features achieved the highest recognition accuracy of 99.14% compared to models based on small-molecule metabolites (91.59%), fatty acids (98.52%), and full-spectrum molecules (98.49%). Furthermore, differential analyses were conducted to assess lamb meat from different origins and feeding methods (grazing versus feedlot) using REIMS fingerprints. Lamb products from the Xilin Gol ranch exhibited significantly lower glycerophosphate (PA) content compared to lambs from other regions, while grazing resulted in significantly lower PA content in lamb meat compared to those fed in feedlots. Additionally, meat from grazed lambs had significantly higher unsaturated fatty acid content, providing molecular evidence for its superior nutritional quality and distinct flavor profile compared to the lambs from feedlot systems. REIMS is a promising tool for rapid discrimination of lamb meat from different origins and feeding systems with high accuracy, offering valuable technical support for lamb origin traceability and quality assessment.