Determination of polar target components: HILIC-MS methods in food analysis

Abstract

Hydrophilic Interaction Liquid Chromatography, abbreviated HILIC, has become one of the most dynamically developing branches of the liquid chromatography technique in recent years. Coupled with mass spectrometry detectors, HILIC-MS systems allow the separation of target components in complex samples, such as foodstuffs of plant or animal origin and feeds, that have been difficult or impossible to retain and detect using High Performance Liquid Chromatography (HPLC) earlier. This paper presents the possibility of using HILIC-MS to determine polar compounds through four specific examples. The test procedures presented include the analysis of a carcinogenic food contaminant, acrylamide, the determination of which in certain food groups is required by law. A further objective of this manuscript is to provide a detailed overview of the HILIC-MS method developed for the detection of water-soluble B vitamins added to foods. Several international standards have been developed for the analysis of B vita-mins, which offer determinations for each vitamin B separately. in comparison, most B vitamins can be measured together using the HILIC-MS technique. This option could be a big step forward for laboratories that analyze B vitamins regularly in a large number of samples. For people living with food intolerance, it is important to know the lactose content of milk-based foods. The HILIC-MS coupled system can also provide a fast and accurate solution for the detection of lactose present in low concentrations, the presentation of which is also the subject of this dissertation. Finally, the paper includes the determination of urea in feed samples. The law prescribes a photometric measurement of urea, but the reliability of this procedure at low concentration levels has been questioned and thus the HILIC-MS method has become prominent as an alternative solution. The applicability of the present analytical methods has been confirmed by successful participation in international proficiency testing programs, sufficiently accurate concentrations detected in control samples, and the certification of fully vali-dated methods by the National Accreditation Authority (NAH).