A New JECFA Method for GC-MS Determination of Propylene Chlorohydrine Residues in Hydroxypropylated Starches.

This article focuses on the development and single-laboratory validation (SLV) of a new gas chromatography–mass spectrometry (GC–MS) method for determining total propylene chlorohydrin (PCH-t) residues in hydroxypropylated (HP) starches used in food. Propylene chlorohydrins (PCH-1 and PCH-2) are byproducts formed during starch modification with propylene oxide, with regulatory limits set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) at 1 mg/kg in dry starch. The new GC–MS method uses aqueous methanol extraction, a programmable temperature vaporization injector, and selected ion monitoring, achieving good linearity, precision (relative standard deviations of 3–5%), recovery (78–112%), and limits of quantification (0.2–0.3 mg/kg) well below regulatory limits. Compared to the outdated JECFA GC–FID method, the new method is more sustainable, less laborious, and increases analytical capacity by 4–5 times. Based on these results and a subsequent multi-laboratory trial, JECFA has decided to replace the old method with this new GC–MS procedure for PCH residue analysis in starches.