A RAPID CAPILLARY GAS-CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OFPROPIONIC-ACID AND PROPIONATES IN BREAD AND BREAD PRODUCTS

A rapid method for the determination of propionic acid and propionates in bread and bread products is reported. The method employs solvent e xtraction, filtration and quantification by capillary gas chromatograp hy using an internal standard. The limit of determination was 10 mg kg -1 propionic acid. The mean recovery rates for spiked bread samples we re 108% at approximately 1000 mg kg-1 (range of 106-110%, coefficient of variation 1.1%), 97% at approximately 2000 mg kg-1 (range 96-98%, c oefficient of variation 0.7%) and 98% at approximately 3000 mg kg-1 (r ange of 97-100% and coefficient of variation of 1.1%). The method offe rs improved sensitivity, precision, chromatographic resolution and a w ider sample analyte concentration range over a previously reported pac ked-column gas chromatographic method and has been applied to the anal ysis of bread, rolls, pitta breads and hamburger buns.