DETECTION OF COMMON-WHEAT (TRITICUM-AESTIVUM) FLOUR IN DURUM-WHEAT (TRITICUM-DURUM) SEMOLINA BY REVERSE-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY (RP-HPLC) OF SPECIFIC ALBUMINS

A method for detecting common-wheat flour in Durum-wheat semolina and low-heat dried pasta by means of RP-HPLC of water-soluble protein is described. This method provides separation of the same specific protein fractions as those determined by IEF according to the Italian Official Method (Official Italian Journal, No. 4, 5 January 1980). A faster sample preparation on solid-phase extraction (SPE) of protein can be adopted. This RP-HPLC method proves to be repeatable (coefficient of variation less than 4%), to have high sensitivity (less than 1% of common-wheat flour detectable), and an accuracy comparable to that of the IEF method. The RP-HPLC method cannot be applied to protein extracted from high-heat dried pasta. The HPLC patterns obtained are poorly resolved and a correct quantification of common-wheat flour cannot be achieved.