微波消解-火焰原子吸收法检测肉制品中的锌元素

Detection of zinc in meat products by microwave digestion-flame atomic absorption spectrometry

目的建立基于微波消解前处理的火焰原子吸收法(FAAS)检测肉制品中锌元素,以评价其替代国标中干法灰化前处理的可能性。方法通过优化消化液配比、消解时间、温度三个关键指标,与国标中干法灰化后测得的肉制品中的锌元素浓度相比较。结果微波消解恒温条件最终确定为20min180℃,消化液为8.0mLHNO3及2.0mLH2O2,回收率99.50%～102.50%,相对标准偏差1.26%～2.91%;并用此法对无锡市场上有关动物蛋白制品中锌含量进行普查,发现猪肉制品、蛋制品和鱼肉制品中锌含量分别为30.25～78.44mg/kg,10.95～26.41mg/kg和14.37～33.75mg/kg。结论在动物蛋白制品中锌元素的检测中,微波消解预处理可以取代干法灰化预处理,具有操作时间短,污染几率小,回收率高等优点。

Objective To evaluate the feasibility of detecting zinc (Zn) in meat products by flame atomic absorption spectrometry (FAAS) based on the pre-processing of microwave digestion, instead of dry–ashing pretreatment. Methods The liquid ratio, time and temperature in microwave digestion were optimized, and comparing with the concentration of zinc in meat products by dry–ashing pretreatment. Results The opti-mized constant temperature condition was finally determined as of 180℃for 20 min and the liquid was 8.0 mL of HNO3 and 2.0 mL of H2O2. The recovery was 99.50%~102.50% and the relative standard deviation (RSD) was 1.26%~2.91%. Zn contents in meat products from Wuxi market were investigated, and the contents of Zn in pork, egg and fish products were 30.25~78.44 mg/kg, 10.95~26.41 mg/kg and 14.37~33.75 mg/kg, respec-tively. Conclusion It is feasible to replace the dry-ashing pretreatment by microwave digestion in the detec-tion of Zn contents in meat products, with the advantages of shorter reaction time, lower polluted probability and higher recovery.