Method for determining residual quantity of dicofol in eel and eel products

Abstract

The invention relates to a method for determining the residual quantity of dicofol in foods, and concretely relates to a method for determining the residual quantity of dicofol in eel and eel products. The method comprises the following steps: carrying out vortex extraction of dicofol alkalization products through using acetone-petroleum ether (1+1V+V), carrying out rotary evaporation of the obtained extract solution at 40DEG C to near dryness, adding n-hexane for dissolving residues, sulfonating by concentrated sulfuric acid to remove lipid impurities and possible-existence 4,4'-DBP in the extract solution, alkalizing dicofol to 4,4'-DBP by using a 10mol / L potassium hydroxide solution and anhydrous ethanol, and determining with a gas chromatograph provided with a micro-electronic capture detector. An external standard method is used for quantification, and when the addition concentration is 0.01-0.05mg / kg, the recovery rate is in a range of 72.2-118.3%, the relative standard deviation is less than 12.6%, and methodologic indexes satisfy the pesticide residual detection requirement. The determination method solves a problem of the unstable dicofol determination result, and eliminates a severe interference problem of complex matrixes.

Description

Technical field: [0001] The invention relates to a method for determining the residual amount of dicofol in food, in particular to a method for determining the residual amount of dicofol in eels and products thereof. Background technique: [0002] Although there are many methods for the detection of dicofol residues in food, they are mainly concentrated in tea, fruit and other plant-derived foods. There are few methods for the detection of dicofol residues in eels and grilled eels, mainly using organic solvent extraction, packed columns or concentrated Measured directly after sulfuric acid purification. Since dicofol is easily decomposed into 4,4'-DBP under gas chromatography conditions (such as high temperature and alkalinity), and the decomposition rate is unstable, resulting in poor repeatability of gas chromatography measurement results. Invention content: [0003] The purpose of the present invention is to provide a method for determining the residual amount of dicof...

AI Technical Summary

Problems solved by technology

[0005] In the present invention, the eel and grilled eel are extracted with an organic solvent, and the lipid impurities and possible 4,4'-DBP in the extract are removed by sulfonation with concentrated sulfuric acid, and then the dicofol is alkalized into 4,4'-DBP and then measured , which solves the problem of unstable determination results of dicofol and eliminates the serious interference of complex matrix, and the detection method meets the requirements of pesticide residue detection