Unveiling the Flavor Secrets of Ginger Peel: Insights from GC-MS and GC-IMS

Ginger ( Zingiber officinale Roscoe ), holds significant potential for utilization due to the volatile organic compounds (VOCs) naturally present in its processing by product, ginger peel. This study systematically analyzed the characteristics of VOCs in ginger flesh and ginger peel before and after drying treatment and evaluated their aroma contributions by HS-SPME-GC-MS and HS-GC-IMS. A total of 93 VOCs were identified by GC-MS. Drying significantly elevated the content of VOCs, especially the concentration of zingiberene, β-sesquiphellandrene, and citral, with the alkenes content in dried ginger peel reaching 1212.92   μg/g. Also, the analysis results of the odor activity value (OAV) showed that β-selinene, β-sesquiphellandrene, and β-myrcene, were the key components contributing to the spicy and fruity aroma in dried ginger peel. Consistently, GC-IMS detected and identified 82 VOCs, and through fingerprinting and partial least squares discriminant analysis (PLS-DA), the volatile differences between ginger flesh and peel were clarified. Furthermore, KEGG enrichment analysis indicated that the monoterpenoid and terpenoid biosynthesis pathways were the main sources of the differential VOCs. Collectively, this study revealed the potential of ginger peel in flavor and pharmacological activity, providing a theoretical basis for the resource utilization and processing technology optimization of ginger peel.