Determination of Propionic Acid and Its Salts in Food by High Performance Liquid Chromatography

In this paper,the pretreatment methods were optimized by different precipitators,extraction conditions and extraction methods,and the effects of different chromatographic columns and mobile phase conditions on separation were investigated. A method for the analysis of propionic acid and its salts in food by high performance liquid chromatography(HPLC)was established. The samples were extracted with water and precipitated with ferrous potassium cyanide-zinc acetate precipitator to precipitate proteins and impurities. The propionic acid and its salts were separated on an Atlantis T3 C18 column using 10 mmol/L diammonium hydrogen phosphate solution as mobile phase,and detected with diode-array detector by external standard method. The method showed that the linearity of propionic acid was satisfied with the good correlation coefficients(R²≥0.999),in the concentration ranges of 5.0~500.0 μg/mL. The average recoveries for the target compound were between 85.1%~109.4%,with RSDs less than 3.78%. The limit of detection(S/N≥3)was 0.02 g/kg,and the limit of quantitative(S/N≥10)the was 0.05 g/kg. This method has the advantages of simple,rapid,and accurate pretreatment,is suitable for the determination of propionic acid and its salts in large quantity food samples. The developed method can provide strong technical support for enterprise quality control and government regulation.