The project, funded by the Irish public health body Safefood, looked at if artisan cheeses labelled as produced on the island of Ireland (IoI) could be described as such.
Teagasc and Queen’s University Belfast investigated analytical methods to provide consumers with necessary assurance of the claimed IoI origin of such products.
Isotopic data separation possibility
They found while it was not possible to confirm the geographic provenance of IoI artisanal cheeses with 100% accuracy, trends in the isotope data suggest the possibility of effective segregation from mainland European, if not GB, cheeses.
“Provenance of processed foods is a significant quality attribute for many consumers and one for which they are willing to pay a price premium. As a consequence, the fraudulent mislabelling or adulteration of high-value foods now occurs on a global scale,” said the report.
“Regulatory authorities and food businesses are focussing greater efforts in combatting food fraud which can have serious ramifications for both revenue and reputation.”
Provenance verification schemes in other countries include the Grana Padano or Parmigiano-Reggiano protected designation of origin (PDO) status for artisan cheeses in Italy.
Concentration and relative ratios of key analytes in food products such as cheese are mainly influenced by animal diet and geographic location.
Previous work has shown the use of multivariate analysis of analytical data comprising elemental and isotopic ratio values can provide confirmation of claimed geographic provenance.
Given that food animals are largely fed a grass-based diet and reside within a certain geographical area, there is potential for developing fingerprint models that can characterise indigenous farmhouse cheeses, according to the report.
“On the basis of the overlapping nature of all of the individual analytes, it may be concluded that no single element or isotope ratio is able to achieve the desired discrimination,” it added.
“Only in the case of δ18O is there the possibility of some degree of separation between cheeses produced on mainland Europe versus those with an IoI or GB geographical provenance.”
Database of samples
A database of farmhouse cheeses to be sampled was established taking into account variables such as milk source, pasteurised vs. raw, hard vs. soft, cultured or not, etc.
Analytical procedures for the inductively coupled plasma mass spectrometry (ICP-MS) and isotope-ratio mass spectrometry (IRMS) techniques were developed and validated.
Data was collected and subjected to univariate statistical analysis and a chemometric software package (‘Unscrambler’) was used for multivariate model development.
The analytical approach enabled development of indicative models for confirmation of geographic provenance in artisan cheeses produced on the IoI.
A total of 131 samples were collected twice during the project (November 2013 and April 2015) and non-IoI cheeses were bought at retail in NI on several occasions.
Cheeses sampled included hard and soft, fermented and non-fermented, bovine, caprine and ovine; some also contained added non-traditional ingredients such as herbs, alcohol, etc.
Gaps in the analytical dataset were encountered for iron, copper, selenium and molybdenum due to technical difficulties or the fact that results were at or below the limit of detection.
Results provide a basis for a follow-on study that would cover a greater geographic region and time span.
“In addition, the analysis of a greater number of elements (particularly transition elements and δ34S), and the application of alternative multivariate data analysis procedures should overcome some of the obstacles encountered here and further the development of robust provenance assurance models.”