Analysis of 3-MCPD Fatty Acid Diesters in Palm Oil Using a Triple Quadrupole LC/MS/MS [LCMS-8030]

Introduction

3-MCPD (3-monochloropropane-1,2-diol) is a by- product that is formed in the production of condiments such as soy sauce when hydrochloric acid is used to accelerate the hydrolysis of vegetable proteins such as defatted soybean and wheat gluten. According to the risk assessment of 3-MCPD by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), 3-MCPD is not considered to be genotoxic or carcinogenic. However, animal tests have indicated that it adversely affects the kidneys if ingested in large quantities over a long period of time. In Japan, it has been confirmed that there is no 3-MCPD present in honjozo (authentically-brewed) soy sauce produced by a traditional method, which accounts for 85 % of the soy sauce produced in Japan. The general dietary intake of 3-MCPD that can be ingested without causing problems is not regulated in Japan. However, measures have been implemented to improve upon production methods and limit the inclusion of 3-MCPD. Recently, the presence of 3-MCPD fatty acid esters have been reported in many foods containing refined edible oils. The toxicity of 3-MCPD fatty acid esters has not yet been clarified, therefore the analysis of 3-MCPD fatty acid ester is very important. The application of GC/MS following derivatization with phenylboronic acid (DGF Standard methods 2009, Section C-Fats) has traditionally been used for analysis of 3-MCPD fatty acid esters, yet direct analysis by LC/MS/MS without derivatization is gaining attention as an attractive alternative method. Significant amounts of 3-MCPD fatty acid esters are present in numerous natural vegetable oils, and their concentration is particularly high in palm oil. Here, we introduce the quantitative analysis of 3-MCPD fatty acid esters in palm oil using LC/MS/MS. Synthetic 3-MCPD-dipalmitoyl ester and 3-MCPD-dioleoyl ester were used as standard samples. Electrospray ionization (ESI) was used as the ionization method and the 3-MCPD-di-fatty acid esters were detected as NH4+ adduct ions due to the addition of ammonium acetate in the mobile phase.

February 29, 2012 GMT