Comprehensive analysis of the impact of extraction methods on the volatile organic compounds and flavor profiles of Piper nigrum L. varieties

This study compared the effects of ultrasound-assisted extraction (UE), Soxhlet extraction (SE), and steam distillation (SD) on volatile organic compounds (VOCs) and flavor profiles of Piper nigrum L. varieties (Vietnamese pepper, VP; Kampot pepper, KP; Dapo pepper, DP). Using electronic nose, GC–MS, and UPLC analyses, UE showed superior retention of VOC diversity and aromatic complexity, while SE maximized piperine retention (e.g., 4551.35 mg/100 g in VP). SD reduced inter-varietal flavor differences, homogenizing volatile characteristics. Despite methodological variations, key aromatic traits of pepper varieties remained distinguishable. KP processed via UE exhibited the highest terpene content (2503.22 mg/100 g), highlighting its aromatic potential. GC–MS data enabled accurate classification of extraction-based flavor profiles via orthogonal partial least squares discriminant analysis. Nine odorants were identified using odor activity value (OAV) and variable importance in projection (VIP). This study provides insight into method-driven flavor differentiation, VOC characterization, and guides strategies for pepper product development.