Comparison of quality and oxidative stability of pumpkin seed (Cucurbita maxima) oil between conventional and enzymatic extraction methods

Pumpkin seed oil was obtained from three extraction methods, namely Soxhlet extraction (SE), cold-pressed extraction (CPE), and aqueous enzymatic extraction (AEE). The impact of the extraction method on physicochemical parameters, fatty acids, bioactive compounds, and oxidative stability of the obtained pumpkin seed oil was assessed. Pumpkin seed oil was rich in unsaturated fatty acids (>80%), squalene (174.1-253.6 mg/100 g), beta-sitosterol (147.7-208.2 mg/100 g), and tocopherols (53.1-73.3 mg/100 g). Extraction methods affected the physicochemical properties and oxidative stability of pumpkin seed oil. Pumpkin seed oil obtained from SE had a higher content of bioactive compounds than AEE and CPE. After an oxidation storage test, pumpkin seed oil obtained from AEE and SE exhibited better oxidative stability than CPE, with AEE performing the best. Overall, this work could provide comparable information to the oil industry to produce high-quality pumpkin seed oils with appropriate extraction methods.