水飞蓟油脂理化性质及氧化稳定性研究

Physicochemical properties and oxidative stability of Silybum marianum oil

对水飞蓟油的理化性质进行测定,采用GC-MS对水飞蓟油脂肪酸组成进行分析,采用液相色谱法测定水飞蓟油中VE的组成;选择在不同温度、空气和光照、金属离子、加入抗氧化剂以及抗氧化剂复配的条件下,采用Schaal烘箱法,对其氧化稳定性进行评价。结果显示,碘值较高,为115.52 g I2/100 g;从水飞蓟油中检测出9种脂肪酸,其中亚油酸含量为48.73%,油酸含量为33.31%,α-亚麻酸含量为0.67%,不饱和脂肪酸含量为82.71%;水飞蓟油中总VE含量为217.57 mg/kg;高温、空气和光照、金属离子加速水飞蓟油脂的酸败;抗氧化剂2-叔丁基对苯二酚(TBHQ)、二丁基羟基甲苯(BHT)、抗坏血酸棕榈酸酯(AP)、茶多酚(TP)、dl-α-生育酚(dl-α-VE)对水飞蓟油抗氧化效果的顺序为:200 mg/kg TBHQ>300 mg/kg TP>100 mg/kg AP>200 mg/kg BHT>100 mg/kg VE。用TBHQ、TP、AP进行复配实验,其中最佳的抗氧化剂组合为:100 mg/kg TBHQ+100 mg/kg AP+300 mg/kg TP。

Physicochemical properties of Silybum marianum oil were determined, its fatty acid compositions were determined by GC/MS, and its tocopherols composition were determined by HPLC. The effects of temperature, air and illumination, metal ions, antioxidants and mixed antioxidants on oxidation stability of Silybum marianum oil were observed by Schaal oven method. The results were as following： Iodine value was 115.52 g I2/100 g. Total 9 fatty acids were determined out. The content of linoleic acid was 48.73%, oleic acid was 33.31%, α-linolenic was 0.67%. The content of unsaturated fatty acids was 82.71%. The total tocopherols contents of Silybum marianum oil was 217.57 mg/kg. The oxidization of Silybum marianum oil was accelerated in the condition of high temperature, air and illumination, metal ions. The effects of antioxidants on the oxidation stability of Silybum marianum oil were investigated, and the effect order was 200 mg/kg TBHQ300 mg/kg TP100 mg/kg AP200 mg/kg BHT100 mg/kg VE. TBHQ, TP and AP exhibited a cooperative synergistic effect, 100 mg/kg TBHQ＋100 mg/kg AP＋300 mg/kg TP exhibited greatest cooperative synergistic effect for Silybum marianum oil.