Determination of Propionic Acid and Propionates in Bread by High-Performance Liquid Chromatography

    ZHANG Yu， LIU Ying* (Tianjin Institute of Food Safety Inspection Technology， Tianjin 30o308， China)

    Abstract： In view of the serious matrix interference， poor repeatability， and difficulty in qualitative and quantitative determination of propionic acidand propionate in existing food detection methods，this study optimized the HPLC detection method for propionic acid and propionate in bread.The sample was mixed with water and 1mol?L^-1 phosphoric acid solution and then ultrasonically extracted. The pH value was adjusted to about 3. The supernatant was filtered through a microporous filter membrane and separated by a C₁₈ chromatographic column. Phosphoric acid aqueous solution and methanol were used as the mobile phase for gradient elution and the determination was performed bya diode array detector.The results showed that the detection limitof this method was (20 0.02g?kg^-1 ，the quantification limit was 0.08g?kg^-1 ，and the recovery rate was 91.5%～105.0% when the content of propionic acid and propionate was 0.08～2.50g?kg^-1 ......