The effect of the subcritical fluid extraction on the quality of almond oils: Compared to conventional mechanical pressing method

• Main Authors: Zhou Qi, Jia Xiao, Liu Ye, Wan Chuyun, Zheng Chang, Li Shugang, Huang Fenghong
• Format: Article
• Language: English
• Published: Wiley 2019-07-01
• Series: Food Science & Nutrition
• Subjects: almond oil; bioactive substances; extraction techniques; thermal stability; Xinjiang cultivars
• Online Access: https://doi.org/10.1002/fsn3.1023

Abstract This study investigated the effect of different almond oil extraction techniques, namely, cold‐press extraction (CP), hydraulic press extraction (HP), and subcritical fluid extraction (SFE), on the fatty acid composition, physicochemical properties, bioactive substances, and thermal stability. The results showed that oleic acid and linoleic acid were the main unsaturated fatty acids in almond oil (AO). The overall physicochemical properties of the AO (SFE) had the better oil quality compared to cold‐press extraction and hydraulic press extraction in three kinds of varieties. Almond oil extracted from SFE contained the highest levels of total phenolics (9.58–11.75 mg/100 g), total phytosterols (92.86–244.21 mg/100 g), total tocopherols, and tocotrienols (48.03–55.74 mg/100 g). Meanwhile, the TG/DTG curves showed AO (SFE) were more thermally stable than AO (CP) and AO (HP) consistent with the result of oxidative induction time. Subcritical fluid extraction may be a useful extraction technology to produce high‐quality almond oils in the future.