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Our technology: fluorescence

Our technology: fluorescence 2019-11-21T23:44:41+00:00

Our analysers are built according to the same principle:

  • LEDs to illuminate the sample at the wavelengths where it is capable of absorbing energy and re-emitting it efficiently in accordance with the phenomenon of fluorescence
  • A CCD-type detector capable of accurately recording the spectra emitted by the sample
  • Software which cleans and extracts the data contained in the spectra and applies the calibration models developed for the application in question.
  • An interface which provides the different measurements chosen to characterize the sample and its quality level.
  • An inert material for checking the instrument’s stability is used before each series of analyses to confirm the quality of the measurements. If the value (set to 100 when it leaves the factory) deviates beyond the confidence interval, we advise you to contact our After-Sales Department.
  • Made in France: the production of all our parts and the assembly of our instruments are handled exclusively in France by the different Chauvin Arnoux teams.

Biological and food products possess natural fluorescence. Some constituents, such as proteins and vitamins, the products of chemical or enzyme reactions, such as Maillard products or hydroperoxides, or contaminants like mycotoxins or pesticides, emit a specific light signal if they are illuminated with visible UV.

Measurement of the fingerprint (complex, sensitive, specific signal generated by the raw product, without preparation, when it is illuminated with visible UV light) faithfully reveals the impact of the processes on the physical and chemical structure of agricultural and food products. These processes may be:

  • biological like the growth of a plant or the germination of a seed,
  • biochemical, as during the secretion of mycotoxins by the Fusarium fungus; some aflatoxin mycotoxins generate a more intense signal
  • chemical, like the production of Maillard products due to the impact of the temperature, or hydroperoxidation due to the impact of oxygen
  • physical and chemical, like protein denaturation due to heat or modification of the wheat’s structure during grinding.

A simple measurement of the sample provides information on the product’s physical and chemical status, thus indirectly indicating the functional properties induced.

To analyse and process this signal, you need to implement complex mathematical processes developed by chemometrics specialists and data scientists.

In particular, the signal must be calibrated if you want to measure a quality indicator. The calibration seeks the relation between the fluorescence signal and the concentration or level of the indicator, itself quantified using laboratory methods called reference methods.

We develop generic types of calibration for turnkey use of measurement on our analysers, as well as specific calibrations applicable to each customer’s individual needs, products and evaluation techniques. Automatic local calibration methods are developed to so that customers remain free to choose how they build models while ensuring that the models target their specific context.

Fluorescence can also be used for direct measurement of fluorescent molecules like proteins, vitamin B2 (riboflavin) or chlorophyll, if the medium is transparent.

This is the case for water or soluble extracts of solid or opaque products: milk, soya, hydrolysates, etc.

This is the method we use to measure the level of non-denatured native proteins with AMALTHEYS. This involves preparing a transparent medium from the milk by precipitating the caseins and whey denatured proteins. A buffer is supplied with a kit for simple, reproducible preparation of the transparent solution of native milk proteins or other dairy products. The analyser measures the natural fluorescence of the amino acid tryptophan, a component of dairy products, whose concentration is proportionate to that of the proteins.

PREPARATION KIT

 

AMALTHEYS®  is delivered in a transportable case with all the products and consumables (distributors, flasks, etc.).

Ready-to-use sample preparation kits have been developed to enable operators with no particular technical skills to perform analyses with AMALTHEYS®. A kit contains all the consumables necessary to perform 100 or 500 analyses depending on your use of the analyser.