超声辅助浸提烤肉蘸料中多元素检测前处理方法

Pretreatment Method of Multi-element Detection in Barbecue Seasoning Assisted by Ultrasonic Extraction

建立烤肉蘸料中多元素检测的前处理方法,通过对微波消解前的样品进行乙醚超声浸提,除去烤肉蘸料中大量油脂,降低样品消化温度,缩短样品消化时间,提高烤肉蘸料多元素检测的准确性。以常规方法和超声乙醚浸提法检出金属浓度差值Q为指标,对铁、铅、汞3种元素进行检测,采用单因素试验和响应面法对超声功率、温度、持续时间等重要因素进行优化;以易挥发元素汞为例进行不同浓度梯度加标回收试验,考察超声浸提对微波消解过程升温梯度和消解时间的影响;对试验方法的检出限、定量限进行计算。结果表明,最优参数为超声功率50 W、超声温度43.6℃、超声时间36 min。在该参数下进行试验,得出Q (Hg)为2.99 mg/kg。试验表明乙醚超声浸提可降低烤肉蘸料微波消解的温度,缩短微波消解时间,减少易挥发元素在消解过程中的损失,对烤肉蘸料等高油脂含量样品中重金属离子检测有重要意义。

A rapid method was established for the pretreatment process of multi-element detection in barbecue seasoning.By ultrasonic extraction,a large amount of oil in sample before microwave digestion was removed,the temperature was lowered,and the time of sample digestion was shortened,so as to improve the accuracy of metal detection.The difference in metal concentration“Q”detected by conventional method and ultrasonic desorption method was used as the index to detect the three elements,namely iron,lead and mercury.Single factor experiment and response surface method were adopted to optimize such important factors as ultrasonic power,temperature and duration.Taking the volatile element mercury as an example,different concentration gradient spiking recovery experiments were conducted,to investigate the effects of ultrasonic extraction on the temperature gradient and digestion duration of microwave digestion process.Calculate the MDL and LOQ of the method.The results showed that the optimal parameters obtained were as follows:ultrasonic power 50 W,ultrasonic temperature 43.6℃and ultrasonic treatment duration 36 min.The Q(Hg)obtained from the experiment based on these parameters was 2.99μg/kg.The results showed that ultrasonic extraction could lower the microwave digestion temperature of barbecue seasoning,shorten the microwave digestion duration,and reduce the loss of volatile elements in the digestion process,which was of great significance for the detection of multi-element in high oil content samples such as barbecue seasonings.