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Determine MOSH/MOAH efficiently

Undesirable mineral oil residues, MOSH and MOAH, are found in numerous foods or food contact materials. The complexity of the analytes and the ubiquitous occurrence of hydrocarbons complicate the analysis and require special analytical systems and sample preparation.

Automated sample preparation and analysis

With the CHRONECT Workstation MOSH/MOAH, analysis can be automated and simplified. The heart of the system is the online LC-GC-FID coupling. Here, an HPLC is connected to a GC via a special interface. The GC uses two FIDs as detectors for simultaneous determination of MOSH and MOAH in one GC run. This halves the analysis time.

The coupling is done via an interface consisting of a control and a heatable valve unit. The temperature of the valve unit can be varied from room temperature to 150°C. The temperature control effectively prevents condensation of the running medium of the HPLC in the valve unit and significantly improves the stability of the system.

The workstation can be configured based on equipment from Agilent or Shimadzu. All control is user-friendly via CHRONOS.

Removal of interferences

Especially when analyzing food, interferences caused by interfering substances are a problem and negatively affect the limit of quantification and accuracy of the analysis. Automatic epoxidation and online alumina purification counteract this.

Room temperature epoxidation in ethanol as solvent was developed by Marco Nestola as part of his work for Axel Semrau and is now part of the current standards and recommendations of the European Union.

The manual process of alumina purification is very time consuming and requires re-injection of the sample. Therefore, Axel Semrau has developed an online purification using an alumina column. This online approach allows the determination of MOSH and MOAH with simultaneous epoxidation and AlOx purification in one run and has found its way into the current DGF method as an alternative approach to the manual approach.

Simplify analysis

During the analysis, the typical chromatogram is noticeable, which shows an unresolved peak cluster, the so-called hump, which must be completely integrated during the determination.

In addition, depending on the question, sitting peaks must be subtracted, as they are considered not to originate from the mineral oil and would thus falsify the result. For a more accurate evaluation of the sample, it is also necessary to obtain partial results for certain boiling ranges. A classical chromatography data system often has difficulties to fulfill these requirements, therefore the software Chrolibri was developed for simple, automatic MOSH/MOAH evaluation.

From practice for practice!

  • Experience since 2010
  • Interference removal with online AlOx-Clean-Up and automatic epoxidation
  • Field-proven MOSH/MOAH evaluation software

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