Determination of flavor enhancers in milk powder by one‐step sample preparation and two‐dimensional liquid chromatography

Abstract

Maltol, ethyl maltol, vanillin, and ethyl vanillin are important food additives as flavor enhancers. To quantify the four additives in milk powder, a novel 2D liquid chromatographic (2DLC) method was developed in this article. In such a 2DLC system, the target fractions eluted from the first dimensional column (C4) are stored onto the trapping column (C8) for subsequent analysis; after that, they were switched into the second dimensional column (C18) by a two-position six-port switching valve. A one-step sample preparation method was used prior to 2DLC chromatographic analysis, which was easy and convenient. After optimization of all experimental parameters, the new method was validated in terms of linearity, LODs, and LOQs, intra- and interday precision, and accuracy. A conventional single-dimensional liquid chromatographic method was also proposed in this work for comparison. In order to evaluate the applicability of the new 2DLC method, five brands of commercial milk powder samples (n = 8) were analyzed. Vanillin and ethyl vanillin were detected in two samples, respectively. It is showed that the 2DLC method is effective in quality control programs of milk powder products.

Online high‐pH reversed‐phase liquid chromatography × low‐pH reversed‐phase liquid chromatography tandem electrospray ionization mass spectrometry combined with pulse elution gradient in the first dimension for the analysis of alkaloids in Macleaya cordata (willd.) R. Br

“…However, due to the diverse structure and complex chemical composition of alkaloids, such 1D LC technology faces enormous challenges [11]. Comprehensive 2D LC (LC×LC) has attracted increasing attention in complex samples such as herb medicine, food additives, and so on for much higher peak capacity compared to 1D LC [12][13][14][15]. For dissociable compounds like alkaloids, they could be well separated by IEC, HILIC, normal phase LC (NPLC), and RPLC according to the difference in hydrophobicity and dissociation [16].…”

Directly-coupled-column ultra-fast liquid chromatography with diode array detection method for the rapid quantification of allergenic disperse dyes in water preconcentrated by magnetic solid-phase extraction

“…Recently, 2D‐LC, which has become a useful tool in the separation scientist's arsenal, shows better separation selectivity and resolving power than conventional LC analysis due to the inclusion of different separation modes . 2D‐LC methods can be classified as heart‐cutting (specific parts of the sample are transferred) and comprehensive (all components are transferred) modes.…”

“…Allergenic disperse dyes, which are contact dermatitis sensitizing agents, containing azo and anthraquinone groups in their structure, can be reduced to potential or known carcinogenic aromatic amines [1]. Some similar allergenic disperse dyes compounds, particularly structural isomers, usually due to the inclusion of different separation modes [6][7][8][9][10][11][12][13][14]. 2D-LC methods can be classified as heart-cutting (specific parts of the sample are transferred) and comprehensive (all components are transferred) modes.…”

Ultrasensitive Electrochemical Sensor for Maltol in Wines Using Graphene Oxide‐Wrapped Amino‐Functionalized Carbon Sphere as Sensing Electrode Materials

“…A variety of techniques have been developed to detect maltol, such as spectrophotometry 8, two‐dimensional (2D) liquid chromatography 9, gas chromatography‐mass spectrometry 10, high‐performance liquid chromatography 11, chemiluminescence 12, and electrochemistry 13–17. Among them, electrochemical techniques are preferred because of their rapid response, convenient use, high sensitivity, good selectivity, time saving and low cost.…”