How can food detect heavy metals and microbes?
The detection methods of heavy metals in foods include colorimetry, turbidimetry, chromatography, spectrophotometry, electrochemical analysis, neutron activation analysis, etc.. The relevant national standards all specify the content determination method of heavy metal elements in food. The following are national standards for detection of lead, cadmium, mercury, and arsenic in food products.
Single sweep polarography, it is a kind of controlled potential polarography, the electrode potential is a linear function of time, by observing current oscilloscope. Potential curves, it is also called the linear displacement oscillopolarographic method, the detection limit was 0.085mg/kg.Two sulfur colorimetric method, the method used two sulfur hydrazone as chromogenic agent, by comparing or measuring the color depth of the solution to determine the content of the component under test, the detection limit is 0.25mg/kg.
Graphite furnace atomic absorption spectrometry, atomizer the graphite furnace atomizer is, will be placed in the graphite tube wall, graphite platform, carbon sample holes or graphite crucible with electric heating to a high temperature so as to achieve atomization, the detection limit is Sug/kg. Flame atomic absorption spectrometry. This method uses flame atomizer and flame atomizer. It consists of three parts: sprayer, premixing chamber and burner. The detection limit is 0.Img/kg.
