Enhancing the Cannabidiol (CBD) Compound in Formulated Hemp (Cannabis sativa L.) Leaves through the Application of Hot-Melt Extrusion
Cannabidiol (CBD) is a non-psychoactive cannabinoid compound found in hemp plants that has recently sparked interest in the biomedical and food industries. CBD is a natural decarboxylated product of cannabidiolic acid (CBDA). In this study, processing parameters were developed to enhance the decarboxylation process of CBDA in hemp leaves using hot-melt extrusion (HME). The hemp leaves were formulated with two different acid-based polymers, namely ascorbic acid (AA) and ascorbyl palmitate (AP), before the HME. The results showed that the carboxylation process of CBDA was increased by at least 2.5 times in the extrudate leaves and the content of the CBD was four times higher when formulated with AP (2800 µg/g) compared with the raw leaves (736 µg/g). The total phenolic and total flavonoid content, as well as the DPPH antioxidant capacity, were higher in the AP formulated extrudate. At the same time, the Δ9-tetrahydrocannabinol (THC) content was reduced by half in the extrudate compared with the raw leaves. It was also observed that double HME processing did not increase the decarboxylation process. It was concluded that the HME process significantly improved the conversion rate of CBDA to CBD in formulated hemp leaves with a reduced THC content.