6种植物油料油脂的品质及氧化稳定性研究

Quality and oxidation stability of the oils from six vegetable oilseeds

为拓宽我国植物油料的开发利用途径,测定了薄壳山核桃、油茶、香榧、核桃、花生、油菜等6种植物种子的含油率及其油脂的总酚、生育酚含量和脂肪酸组成,并采用加速氧化试验对其油脂的氧化稳定性进行评价,探究了各项品质指标与氧化稳定性指标的相关性。结果表明:薄壳山核桃仁的含油率最高(73.07%),且其油脂的总酚含量最高(12.6 mg/kg),香榧籽油的生育酚总量最高(114.90 mg/100 g);6种植物油中有5种共同脂肪酸,分别为棕榈酸、硬脂酸、油酸、亚油酸和花生烯酸;6种植物油中,薄壳山核桃油的氧化稳定性最强,其酸值、过氧化值、共轭二烯值、共轭三烯值、羰基值的变化幅度均较小,氧化诱导时间(OSI值)处于最高水平,核桃油的变化幅度较大;加速氧化过程中6种植物油的油酸、亚油酸、不饱和脂肪酸、饱和脂肪酸含量均无明显变化;油脂的OSI值与油酸、生育酚、总酚含量呈显著正相关,与亚油酸、亚麻酸含量呈显著负相关。综上,薄壳山核桃含油率高,薄壳山核桃油含有较高的总酚含量和较好的氧化稳定性,是一种优质的食用油,可作为营养保健油开发利用。

In order to broaden the development and utilization of vegetable oilseeds in China,the oil contents of six vegetable oilseeds,including Carya illinoinensis(Wangenh.)K.Koch,Camellia oleifera Abel.seed,Torreya grandis seed,walnut,peanut and rapeseed,as well as the total phenol content,the tocopherol content and the fatty acid composition of their oils were determined,the oxidation stability of their oils was evaluated by the accelerated oxidation test,and the correlation between the quality indexes and the oxidation stability indexes was explored.The results showed that Carya illinoinensis(Wangenh.)K.Koch kernel had the highest oil content(73.07%)and the highest total phenol content in its oil(12.6 mg/kg),and total tocopherol content in Torreya grandis seed oil(114.90 mg/100 g)was the highest.There were five common fatty acids in the six vegetable oils,which were palmitic acid,stearic acid,oleic acid,linoleic acid,and arachidonic acid;and among the six vegetable oils,Carya illinoinensis(Wangenh.)K.Koch oil had the strongest oxidative stability,with small changes in acid value,peroxide value,conjugated diene value,conjugated triene value and carbonyl value,and the oxidation induction time(OSI value)was at the highest level,and larger change was found in walnut oil.There was no significant change in the contents of oleic acid,linoleic acid,unsaturated fatty acid and saturated fatty acid of the six vegetable oils during accelerated oxidation.There was a significant positive correlation between the OSI value of the oils and the contents of oleic acid,tocopherol and total phenol,and a significant negative correlation with the content of linoleic acid and linolenic acid.In conclusion,Carya illinoinensis(Wangenh.)K.Koch has high oil content,its oil has high total phenol content and high oxidative stability,so Carya illinoiensis(Wangenh.)K.Koch oil is a high-quality edible oil and can be developed and utilized as a nutritional and health care oil.