Brazil Nut Oil Extraction Using Subcritical n-Propane: Advantages and Chemical Composition

In order to provide an effective and environmentally correct alternative for oil extraction, subcritical n-propane was used under different temperature and pressure conditions to obtain Brazil nut oil. The composition of the oil was determined and compared to the oils obtained by conventional methods. The result of the extraction yield obtained using subcritical fluid extraction (SFE) at 60 ºC, 6 MPa and granulometry &lt; 1.40 mm (63.13%) presented minor differences to the yield obtained by Soxhlet extraction (SE) (68.44%) and Bligh and Dyer extraction (BD) (59.54%). The composition in fatty acids was similar regardless of the method of extraction used. Oxidized triacylglycerols (TAGs) were found in the oils extracted by SE and BD while they were not detected in the oils extracted by SFE. The quantity of bioactive compounds was higher in the oils obtained by SFE. Thus, the SFE using n-propane preserves the nutritional characteristics and lipophilic components of the oil, besides improving the availability of bioactive compounds from an effective “green extraction” without the use of toxic solvents.为给油脂提取提供一种高效且环境友好的替代方案，本研究采用亚临界正丙烷，在不同温度与压力条件下提取巴西坚果油。研究人员对所得油脂的组成进行了测定，并将其与传统方法提取的油脂进行对比。在60℃、6 MPa且颗粒度<1.40 mm的条件下，采用亚临界流体萃取（subcritical fluid extraction, SFE）所得的提取率为63.13%，与索氏提取法（Soxhlet extraction, SE）的68.44%以及布雷格-戴尔提取法（Bligh and Dyer extraction, BD）的59.54%相比仅存在细微差异。无论采用何种提取方法，所得油脂的脂肪酸组成均较为相似。索氏提取法与布雷格-戴尔提取法所得油脂中均检出氧化三酰甘油（triacylglycerols, TAGs），而亚临界流体萃取所得油脂中未检出该类物质。亚临界流体萃取所得油脂中的生物活性化合物含量更高。由此可见，采用正丙烷的亚临界流体萃取作为一种无需使用有毒溶剂的高效“绿色提取”技术，不仅可保留油脂的营养特性与脂溶性成分，还能提升生物活性化合物的可得性。