Method KM 14 "Screening, identification and determination of volatile and semi-volatile substances, including aroma components, by GC/TOF-MS" is intended for screening and determination of volatile and semi-volatile substances. By profiling and analyzing these substances, we can characterize the aroma composition of a given product, or identify substance(s) that cause a negative sensory perception (off-flavour) or are undesirable for health. In more complex cases of examination, the laboratory provides detailed documentation of analyses and expert interpretation of measured data. Instrumental techniques used for this type of analysis are:
(i) Gas chromatography coupled with high-resolution Q-TOF mass spectrometry
(ii) Gas chromatography coupled with high-resolution TOF mass spectrometry
This method is used not only for the complex analysis of food, beverages, and natural products but also for natural and synthetic flavorings used in food, cosmetics, electronic cigarettes, and other aromatized products. Terpenes or extraction solvent residues are determined quantitatively using this method.
Metabolomics originally emerged as a relatively new technique in systems biology that focuses on the complex characterization of (low molecular weight) metabolites and their relationships in biological systems. In the chemical analysis of food, metabolomic strategies are somewhat unconventional and their development has been conditioned by the availability of modern instrumental techniques and the possibility of routine application of advanced mathematical and statistical methods.
Foods differ from each other in the abundance, concentrations and relative abundance of low molecular weight metabolites and these complex metabolic characteristics or properties can be measured and the profiles obtained (metabolomic fingerprints) can be considered as similarly diagnostic for a given object as fingerprints. Using this method, it is possible to directly compare the differences between the profiles of a huge number of metabolites of a test food and a target food for the purposes of adulteration identification, food classification and traceability, and even sometimes an indication of where or when a food was produced. The use of chemometric or statistical tools here helps to compare and analyse the differences between the reference model and the test object to determine whether and how significant differences exist and to describe causal relationships.
Method KM 15 "Identification and determination of metabolome components by fingerprinting/profiling by UHPLC-HRMS/MS is intended for the determination and characterisation of the profile of low molecular weight organics (with a molecular weight less than about 1200 Da), ionizable and detectable by one of the techniques described in this methodology:
(I) Direct Analysis in Real Time (DART) technique in conjunction with an Orbitrap-MS mass spectrometer,
(ii) in addition, by ultra-performance liquid chromatography coupled to a high-resolution mass spectrometer with a Q-TOF MS-type analyser (alternatively equipped with an ion mobility technique, IMS); or
(iii) an ultra-performance liquid chromatography technique coupled to a high-resolution mass spectrometer with an Orbitrap-MS type analyser and also using
(iv) supercritical fluid chromatography (SFC) in conjunction with a high-resolution mass spectrometer with a quadrupole-time-of-flight (Q-TOF MS) analyser,
Analyses are most commonly performed in extracts of foods, crops and food raw materials, food supplements, novel foods or feeds, as well as in beverages fats and oils, human and animal tissues and body fluids, sediments and soils, and in the toys.
Some examples of applications:
- Authenticity of safron (Crocus sativa),
- Metabolic profiling for the detection of individual fruit species and subspecies in fruit products
- Verification of the authenticity of Aloe vera-based products and analysis of hydroxyanthracene derivatives
- Authenticity of Tribulus terrestris and analysis of steroidal saponins