A Novel Analytical Method for Rapid Detection of Batch‐To‐Batch Variation and Storage Stability of Natural Flavouring Materials by Online Py‐ <scp>GC</scp> / <scp>MS</scp> Technology

ABSTRACT Ensuring batch‐to‐batch consistency and storage stability of natural flavouring materials is a critical yet challenging task in quality control for consumer product industries. This study presents and validates a novel application of online pyrolysis–gas chromatography/mass spectrometry (Py‐GC/MS) as a rapid tool for assessing flavour quality. By generating comprehensive pyrolysis fingerprints, the method profiles both volatile and non‐volatile constituents within complex matrices. The Py‐GC/MS method was first systematically validated, demonstrating satisfactory precision, reproducibility, and sensitivity. It was then applied to three representative flavourings: wild jujube tincture, lemon oil and apple juice concentrate. The results successfully discriminated between production batches, revealing high compositional consistency in processed extracts (wild jujube tincture and apple juice concentrate). Furthermore, the method effectively monitored storage‐induced chemical changes, detecting subtle marker shifts in stable tinctures as well as a pronounced oxidative degradation pathway in lemon oil, with identification of key aging‐related compounds. This single automated analysis provides a holistic, application‐relevant thermal fingerprint that surpasses conventional profiling techniques. The study demonstrates that online Py‐GC/MS is an efficient and reliable quality control tool suitable for natural flavouring materials screening, batch acceptance testing and shelf‐life prediction, offering significant technical support for quality assurance in the flavour and related industries.