Chapter 5 - Direct analytical detection methods for the food-borne toxicants glycidyl esters

Abstract

Following the detection of 2-MCPD esters, 3-MCPD esters, and glycidyl esters in foods, especially in refined edible oils and fats and complex foods containing these oils as ingredients, many efforts have been undertaken by industry as well as research institutes to minimize their amounts due to the fact that after consumption, cleavage of the esters to form harmful free 2-MCPD, 3-MCPD, and glycidol has been shown. Thus, there is a huge demand for robust, quick, and sensitive quantitation methods. On the one hand, the so-called indirect methods, revealing the sum of 2-MCPD esters, the sum of 3-MCPD esters, and the sum of glycidyl esters, were established. On the other hand, the so-called direct methods, enabling the quantitation of individual esters, were developed. The latter have the important benefit that the intact esters are quantitated, providing more detailed information that can be used for toxicological risk assessment by consumption of foods; however, the drawback of this approach lies in the need for more reference compounds and more stable isotopically labeled internal standards for quantitation. This chapter will highlight the development of direct quantitation methods for glycidyl esters, primarily based on LC-MS/MS techniques via stable isotope dilution analysis. The data obtained using different direct methods developed in the early stages will be discussed, including a comparison of the results (based on the respective sum of the glycidyl esters) to data obtained using indirect methods.