柠檬草精油对食用油脂的抗氧化性研究

目的]优化微波辅助提取柠檬草精油的工艺条件,研究柠檬草精油的抗氧化性。方法]以柠檬香茅为材料,采用微波辅助技术对柠檬草精油进行优化提取,并以猪油为介质,以过氧化值为指标,考察提取物的抗氧化性及其与柠檬酸、VC的协同抗氧化效果。结果]各因素对提取率的影响主次顺序为:料液比微波功率微波时间。微波辅助提取柠檬草精油的最佳工艺条件是:料液比1∶15、微波提取时间5 min、微波功率为350 W。在此条件下,柠檬草精油的出油率为1.19 ml/100 g。柠檬草精油在猪油中的抗氧化性与BHT的相近,但不如TBHQ的强。柠檬草精油与柠檬酸和VC在油脂中均有协同增效作用,但以VC效果较好。结论]柠檬草精油在食用油中具有良好的抗氧化性能,其抗氧化性与BHT接近。

Study on Oxidation Resistance of Essence Oil from Lemon Grass to Edible Fats

Objective] The study aimed to optimize the technology conditions for extracting the essence oil from the lemon grass by the microwave assisted technology and study the oxidation resistance of the essence oil from the lemon grass.Method] With the lemon citronella as the material,the essential oil from the lemon grass was made for the optimized extraction by the microwave assisted technology.With the lard as the medium and the peroxide value as the index,the oxidation resistance of the extracts and its collaborative antioxidant effect with the citric acid and VC were investigated.Result] The influences of various factors on the extraction rate were in order of material-liquid ratio > microwave power > microwave time.The technology conditions for extracting the essence oil from the lemon grass by the microwave assisted technology were as follows: the material-liquid ratio of 1∶ 15,microwave time of 5 min and microwave power of 350 W.Under the conditions,the oil yield of the essence oil from the lemon grass was 1.19 ml/100 g.The oxidation resistance of the essence oil from the lemon grass was close to that of the BHT,but wasn’t strong with that of TBHQ.The essence oil from the lemon grass,citric acid and VC all had collaborative antioxidant effect in the lard,in which VC got better effect.Conclusion] The essence oil from the lemon grass had the good oxidation resistance in the edible fats and its oxidation resistance was close to the BHT.