Analysis of Food Fraud & Authenticity

Honey carries a high risk of economically motivated adulteration. Through the addition of industrially produced syrups, honey can be blended in a targeted manner and thus a higher profit can be achieved.

According to Honey Directive 2001/110/EC no additions other than honey shall be made nor shall any constituent particular to honey be removed. A honey diluted with syrup would therefore not correspond to EC Honey Directive and would be evaluated as being misleading.

In order to examine the authenticity of honey, there are different methods, which are sensitive for different kinds of the falsification. These include specific markers, such as rice syrup markers, but also indirect evidence of honey foreign enzymes or the oligosaccharide profile. There are also non-specific screening methods.

Non-specific screening methods to detect adulteration:

NMR analysis

In NMR screening, the entire profile of the honey is examined and compared with a database based on authentic honeys. Deviations in the profile can indicate an adulteration of the honey. In addition to indications of adulteration, the profile also shows deviations in honey quality, for example with regard to the heating parameter HMF or a fermentation of the honey.

HR-MS

A multitude of markers for syrup addition are detected at once with this method by Orbitrap. Markers in use only occur in syrup but not in honey. Thus, the presence of any marker in honey point to addition of syrup to honey.

Specific adulteration markers:

Specific markers have been identified for certain syrups; these do not naturally occur in honey. For example, there are specific markers for rice syrup and beet sugar syrup.

13C isotope analysis

The d-13C isotope values of honey, protein and the individual sugars can be used to detect sugars foreign to honey (especially C4 sugar).

Indirect proof of adulteration:

Honey foreign enzymes

Enzymes are often used for the production of syrup, for example invertase is used for the production of invert sugar syrup. By detecting the activity of these honey foreign enzymes, the addition of sugar syrups is thus indirectly detected.

Oligosaccharides

The detection of foreign oligosaccharides in honey proves the presence of sugar syrup produced from starch.

Caramel colour (E150d)

Caramel colour (E150d) may be added to honey to restore the colour of honey after the addition of light syrup. Thus, caramel colour serves as indirect evidence for the addition of syrup.

Like honey, agave syrup can also be diluted by adding cheaper syrups in order to achieve a higher profit.

The d-13C isotope values of the agave syrup and the individual sugars can be used to detect foreign sugars.

A further possibility to detect adulteration in agave syrup is NMR analysis. The profile of agave syrup is compared with a database of authentic agave syrups. Deviations in the NMR profile can indicate adulteration of the agave syrup with other syrups.

The two main species in world trade are Coffea arabica (Arabica) and Coffea canephora (Robusta) with Arabica having the bigger market share. According to Regulation (EU) No. 1169/2011 Article 7 “Food information shall not be misleading […]”. Therefore a product labelled as “100 % Arabica” must contain 100 % Arabica coffee and shall not have added any Robusta coffee. Arabica and Robusta coffee beans look different in shape and size, so they can theoretically be distinguished visually. But due to natural variances differentiation can be quite difficult and is not possible for ground coffee. Therefore the visual identification is not always possible resp. reliable and is very time consuming.

16-O-methylcafestol has been identified as a marker substance in the past. This substance is only present in Robusta coffee and not in Arabica coffee. If the marker 16-O-methylcafestol is detected, the presence of Robusta coffee is thus proven and the coffee may not be labelled as “100% Arabica”.