P23 | Transfer of phytocannabinoids from hemp-based feed to goat milk and cheese: quantitative assessment by mass spectrometry

A. Gallo^1|2, A. Siciliano¹, G. Guadagnuolo¹, G. Cappelli¹, G. Rofrano², L.J. D’auria², P. Gallo¹ | ¹Istituto Zooprofilattico Sperimentale del Mezzogiorno, Portici (NA); ²Centro di Referenza Nazionale per l’Analisi e Studio di Correlazione tra Ambiente, Animale e Uomo, IZS Mezzogiorno, Portici (NA), Italy

Purpose. The increasing spread of Cannabis sativa L. in the agri-food sector has led to the inclusion of its derivatives in animal feed as well. However, it is still unclear to what extent individual phytocannabinoids can transfer into animal products and pose a risk to consumers, as indicated by Recommendation (EU) 2016/2115. The aim of the study was to quantify the transfer of phytocannabinoids from hemp-containing feed to goat milk and cheese (robiola), evaluating how the concentrations vary depending on the dosage administered. Materials and Methods. Five groups of 10 Cilento goats (A, B, C, D, E), homogeneous in age, days since kidding, number of lactations, and morphological characteristics, were fed 1,000 g/day of pelleted feed for 60 days, administered in two daily rations. The rations varied in hemp concentration and consequently in Δ9-Tetrahydrocannabinol (Δ9-THC) content: Group A (1250 mg/kg), B (625 mg/kg), C (250 mg/kg), D (125 mg/kg), E (0 mg/kg, control). The bulk milk from each group was processed into robiola, a cheese made without high heat treatment, to avoid thermal degradation of phytocannabinoids. All samples (milk and cheeses) were analyzed at the IZSM Chemistry Department using UHPLC-UMRS (milk; internal method MP/CH/168 Rev.4) and LC/ESI-MS/MS (cheeses; internal method MP/CH/167 Rev.4), both accredited methods. Results. In bulk milk, the main phytocannabinoids detected were: Cannabidiol (CBD) up to 4.862 ppm in group A, Δ9-THC 0.3379 ppm in group A, and Δ8-Tetrahydrocannabinol (Δ8-THC) 0.5802 ppm in group A, with a consistent decrease in groups with lower hemp rations. Δ9-THC was also found in group E with values of 0.04285 ppm. Other compounds detected were: Cannabidiolic Acid (CBDA), Cannabigerol (CBG), and Cannabinol (CBN) in lower concentrations; Tetrahydrocannabinolic acid (THCA) was present only in group A with values of 0.00113 ppm. In cheeses, an increase in the concentration of the more lipophilic phytocannabinoids has been observed. CBD reached 2.72 ppm in group A; 9-THC, 0.397 ppm in group A, and was also detected in group E at 0.031 ppm. THCA, absent in milk except in group A, was detected in all cheeses at similar levels (0.05–0.06 ppm). 8-THC and CBN were not detected in the cheeses, while CBDA and CBG showed stable, albeit low, concentrations across all groups. Discussion. The study highlighted a dose-dependent transfer of phytocannabinoids from feed to milk and subsequently to cheese. The higher concentration of CBD and 9-THC in cheeses compared to milk is attributed to their affinity for the lipid fraction. The presence of THCA in cheeses, while almost absent in milk, suggests possible enzymatic or chemical conversion phenomena of other phytocannabinoids. The absence of 8-THC and CBN in cheeses, despite their presence in milk, could be linked to degradation or transformation during cheesemaking, even without exposure to high temperatures.