From Field to Extract: Controlling Post-Harvest and Extraction Variables for Reproducible Recovery of Cannabinoids and Terpenes from Cannabis sativa L. by Sequential Hydrodistillation and Pressurized Liquid Extraction

Valorizing the full phytochemical profile of hemp (Cannabis sativa L.), including the synergistic activity often referred to as the “entourage effect,” requires efficient recovery of both its cannabinoid and terpene fractions. However, initiating cannabinoid decarboxylation through high drying temperatures leads to substantial loss of the terpene profile, making the two objectives thermally incompatible in conventional workflows. This study first investigated the influence of post-harvest conditions on cannabinoid content and decarboxylation using a Design of Experiments approach, and then developed a process bypassing the drying step, based on freezing and hydrodistillation, to formulate a broad-spectrum product combining high cannabinoid and terpene content. Two hemp chemotypes (Felina 32, CBD-dominant; Santhica 27, CBG-dominant) were characterized, and drying temperature was identified as the critical parameter governing decarboxylation. Freezing before hydrodistillation preserved monoterpenes and improved essential oil yield relative to oven-drying, while the heat of hydrodistillation itself drove in situ cannabinoid decarboxylation, enabling near-complete recovery in a subsequent pressurized liquid extraction step. This integrated process achieved near-quantitative recovery of cannabinoids and monoterpenes across independent production batches, with encouraging recovery of sesquiterpenes, supporting the standardized and reproducible valorization of hemp, especially for pharmaceutical applications.