Quality indexes and composition of 13 commercial hemp seed oils

Cold-pressed hemp seed oil can be a valuable source from both nutritional and sustainability points of view. Thirteen hemp seed oils (HSOs) have been characterized, also with useful data about the bioactive compounds present in this product, considering that the hemp seed oil industry lacks of specific standard for the quality control of this oil. Samples were collected from the market and 12 of the 13 HSOs were claimed to be coldpressed on the label. The hydrolytic and oxidative states were investigated according to the standards provided by the Codex Alimentarius. HSOs showed a wide range of free acidity (from 0.89 ± 0.02 to 4.58 ± 0.03 mg KOH/g) and peroxide values (from 3.97 ± 0.25 to 23.89 ± 0.74 mEqO2/kg). The HSOs had a ratio of ω6:ω3 from 2.60 to 3.67. γ-tocopherol ranged from 594 to 967 mg/kg and a wide range in the content of chlorophylls (from 0.78 to 75.7 mg/kg) and carotenes (from 2.53 to 33.9 mg/kg) was seen. This suggests that different extraction conditions (production plants, extraction temperatures and time) were used. Cannabinoids were also present: cannabidiolic acid (CBDA) (from 4.25 to 91.6 mg/kg), Δ9-tetrahydrocannabinol (Δ9-THC) (up to 5.29 mg/kg) and tetrahydrocannabinolic acid (THCA) (up to 5.00 mg/kg). Lastly, the analysis of the volatile profile highlighted the presence of some specific cannabis terpenes, such as α-pinene and β-pinene.