3-Monochloro-1,2-propandiol (3-MCPD) in soy sauce from the Bulgarian market

The 3-monochloro-1,2-propandiol (3-MCPD) levels in soy sauces which contained hydrolysed vegetable protein were evaluated for the Bulgarian market. For analysis of 3-MCPD, a gas chromatography-mass spectrometry (GC-MS) method was applied with a linear range of 0.03-2.00 μg mL⁻¹ and a limit of detection (LOD) of 2.3 μg kg⁻¹ and a limit of quantification (LOQ) of 3.4 μg kg⁻¹. At these levels, the standard deviation was 5.1%, with recoveries between 81% and 102%. The method was applied to the analysis of 21 samples of soy sauce from the Bulgarian market. Results ranged from 3.7 to 185.6 μg kg⁻¹. Soy sauces produced from hydrolysed soy protein contained higher levels of 3-MCPD than naturally fermented sauces. In 38.4% of samples of Bulgarian origin, the 3-MCPD content was above the EU limit of 20 μg kg⁻¹. In all analysed samples, 33.3% had a 3-MCPD content above the EU limit.