Comprehensive food sample analysis

This application note shows how the distribution of various chemical compounds in food products could be successfully visualised along with surface topography information, leading to a more comprehensive understanding of the product and the production process.

In the food industry, various ingredients, additives and biopolymers (such as emulsifiers, stabilisers, carbohydrates or thickeners) are commonly used to optimise the texture or flavour of food. The distribution and microstructure of the ingredients strongly influence the properties of the final product. Therefore, research and development, as well as quality control, require powerful analytical tools to study the distribution of the various compounds in the food. Raman imaging has proven to be a valuable technique for food analysis.1-5

The Raman principle

The Raman effect is based on inelastic scattering of excitation light by the molecules of gaseous, liquid or solid materials. The interaction of a molecule with photons causes vibrations of its chemical bonds, leading to specific energy shifts in the scattered light that can be detected in its Raman spectrum. Any given chemical compound produces a particular Raman spectrum when excited and can be easily identified by this individual ‘fingerprint’. Raman spectroscopy is thus a well-established, non-destructive method for analysing the molecular composition of a sample.