DART mass spectrometry for rapid screening and quantitative determination of cholesterol in egg pasta

Abstract

To ensure that egg-containing products, such as dried eggs and egg pasta, conform to the technological and legislative requirements for egg content, methods are needed to determine the amount of cholesterol in such products. The conventional approach, direct saponification and hexane extraction followed by cholesterol determination by gas chromatography coupled to a flame ionization detector, is very time consuming. Therefore, we developed a rapid method on the basis of direct analysis in real time coupled to time-of-flight mass spectrometry. Samples were prepared simply by solvent extraction followed by extract filtration. The optimization of certain parameters, including the solvent used and direct analysis in real time ionization gas temperature, had a pronounced effect on the intensities of the produced ions, in particular, the molecular and dehydrated ions of cholesterol and its deuterated analog, cholesterol 2,2,3,4,4,6-d(6) which was used as an internal standard. For the developed method, limits of detection and quantification were 0.03 and 0.05 mg g(-1) respectively. The results of the real samples were compared with those obtained using the conventional approach [limit of detection = 0.002 mg g(-1) and limit of quantification = 0.05 mg g(-1)], and it was found that, although the results obtained using the conventional approach were more accurate, our developed method is much simpler and faster, where the time was dramatically reduced by 87% for executing a screening analysis.

Applications of DART‐MS for food quality and safety assurance in food supply chain

“…Solvent extraction (SE) is a relatively simple preparation method before introducing analytes into DART ion source. Among all organic solvents, methanol (Farr e, Pic o, & Barcel o, 2013), ethanol (Albalaa et al, 2014), acetonitrile (Zachariasova et al, 2010), ethyl acetate (Schurek et al, 2008), diethyl ether (Morlock, Ristivojevic, & Chernetsova, 2014), toluene (Rothenbacher & Schwack, 2010), hexane (Albalaa et al, 2014), and cyclohexane (Cajka et al, 2013b) are frequently used for extraction. In conjunction with ultrasound-assisted method, the extraction yield and speed could be increased (Vaclavik et al, 2010a;Farr e, Pic o, & Barcel o, 2013).…”

“…The content of cholesterol in dried eggs and egg pasta is also suggested to be controlled. Pretreated by SE before filtration, cholesterol and the internal standard (i.e., deuterated analog, cholesterol 2,2,3,4,4,6-d 6 ) were detected, leading to LOD and LOQ at 0.03 and 0.05 mg g À1 , respectively (Albalaa et al, 2014). Some foods and medicine share similar origin.…”

Internal Energy Deposition in Dielectric Barrier Discharge Ionization is Significantly Lower than in Direct Analysis in Real-Time Mass Spectrometry

“…DART emitter nozzles are typically positioned between 8 and 15 mm from the entrances of mass spectrometers. [50][51][52] The sample vial that delivers analyte vapour to the DART source was kept in the same position for all experiments (,1 cm below the capillary entrance to the mass spectrometer). The temperature of the capillary entrance to the mass spectrometer was set to 1508C, which is the minimum temperature that enabled the detection of benzylammonium in reasonably high abundances under these conditions.…”

Evaluation of ice‐tea quality by DART‐TOF/MS

“…are well described in the literature . This technique is used for inspection of food, especially determination of pesticides, fatty acids and cholesterol, and for assessing quality and authenticity of soft drinks, olive oils, mustards etc . The DART technique has been used for monitoring tea fermentation and manufacturing …”

“…[17][18][19] This technique is used for inspection of food, especially determination of pesticides, fatty acids and cholesterol, and for assessing quality and authenticity of soft drinks, olive oils, mustards etc. [20][21][22][23] The DART technique has been used for monitoring tea fermentation and manufacturing. [24] A lot of articles have focused on tea but there are a negligible number of articles focusing on products based on tea extracts (ice-teas etc.).…”