Determination Of Food Additives And Illegal Additives By HPLC In Food

The food additive, as an important part of the food industry, is used to improve the qualities such as color, smell and taste of the food. They are chemical synthesis or natural substances added to food to prevent spoilage and meet the need of processing. Currently, Food additives are mostly artificial compounds, their excessive using will cause various degrees of harm. Illegal additive in food has prohibited by the nation in food production. Excessive addition of food additives or using of illegal additives out of the additives list will be harmful to humans. In this paper, we used a simple, rapid, and efficient pre-treatment technology, and combined with high performance liquid chromatography to develop a qualitative and quantitative research on a variety of food additives and illegal additives. The main results and conclusions are as follows.1. A new method for the determination of8antioxidants in foods by reversed high performance liquid chromatography method was developed. Samples were extracted by ethyl acetate-cyclohexane (1:1, V/V) and cleaned-up by gel penetrating chromatogram (GPC) and then separated on a C18column in a gradient elution, and the mobile phases were1%acetic acid-acetonitrile. Under the added level of2μg/g,20μg/g and200μg/g, the recoveries of the method were at75.62%～104.19%with the RSDs lower than10%, and the detection limits were0.31-1.46μg/g.2. An analytical method, which is solid-phase extraction followed by high performance liquid chromatography, was developed for the determination of7kinds of acidity regulators in food, including Tartaric acid, malic acid, lactic acid, acetic acid, citric acid, fumaric acid and adipic acid. The sample was purified by an SAX solid-phase extraction cartridge and then separated on a Synergi4u Hydro-RP column in a gradient elution, and the mobile phases were potassium dihydrogen phosphate buffer-acetonitrile (adjusted with phosphoric acid to pH3.0). In addition, the column temperature was25℃, the detection wave length was set at210nm. In this condition, the acidity regulators could be separated well without interference by other peaks. The recoveries of the method were between86.1%and102.6%, with the relative standard deviations less than10%. The method is simple, rapid, sensitive and reproducible, and can be used for the routine analysis of the acidity regulators in food.3. A new method was established for determining15kinds of industrial synthetic dyes in condiment using solidphase extraction-high performance liquid chromatography (SPE-HPLC). Firstly, the samples were extracted by methanol-water (1:1, V/V) and purified by solid phase extraction column. Then, the chromatographic separation was achieved on a LnuaC18-250mm column by linear gradient elution. And the mobile phases were10mmol/L ammonium acetate-acetonitrile (containing1%acetic acid). The results showed that15kinds of industrial synthetic dyes were separated efficiently. The recoveries of15kinds of synthetic dyes spiked in condiment were between84.6%and114.2%with the relative standard deviations in0.9%～10.3%. The detection limits of this method was0.05～0.18mg/kg for15kinds of synthetic dyes. The method was sensitive and accurate, and could be used for simultaneous determination of15illegally added industrial synthetic dyes.