Aflatoxin M1 analysis: performance in fresh cheese VS seasoned cheese

In 2022, we wanted to offer the PT for the research of Aflatoxin M1 in cheese (code CE2111) in a slightly different formulation. Compared to previous years in which only one Test Material was provided with fresh cheese (Robiola/Ricotta type) as a matrix, in 2022 participants were provided with two Test Materials with different matrices and concentrations:

  • Test Material-1 (CE2111-1) = Fresh cheese (Robiola/Ricotta type). Assigned value: 239,22 ng/kg;
  • Test Material -2 (CE2111-2) = Hard Cheese (Parmesan type), provided in the form of a slurry. The slurry ensured the homogeneity of the sample. Assigned value: 371,00 ng/kg.

A total of 29 laboratory, from 11 different countries (Austria, Bosnia and Herzegovina, Burkina Faso, Burundi, Italy, Germany, Malaysia, Mongolia, Serbia, Sri Lanka and Uganda), subscribed to this circuit.

Results: 2022 PT VS previous years

In general, the results of the last year’s PT for Aflatoxin M1 in cheese were satisfactory.

With regard to participants’ evaluations using confirmatory methods, 13 out of 15 laboratories achieved a satisfactory z-score (|Z-score| or |Z’-score| < 2 (n)), with a satisfaction rate of 87%, which is higher than in previous years (2020 = 62%, 2019 = 86%).

Overall confirmatory evaluation

Test Material CodeAnalyteNumber of labs|Z-score| or
|Z’-score| < 2 (n)
|Z-score| or
|Z’-score| < 2 (%)
CE2111A-1 aflatoxin M1 15 13 87
CE2111A-2 aflatoxin M1 15 13 87

From the z-scores obtained from the participants using screening methods, a slightly higher number of unsatisfactory z-scores were found for the hard cheese matrix.

However, despite the positive results of this circuit, industrialisation tests were carried out to provide in 2023 a sample of hard cheese that is not in slurry form. This was done in order to offer a sample more similar to those used in the routine.

We are therefore delighted to reintroduce again for 2023 the:

PT for the research of Aflatoxin M1 in hard cheese (code CE3601) October Round 2023

  • Test Material: hard cheese, 1 sample of 50g
  • Analytes: Aflatoxin M1
  • Indicative concentration: < 600ppb
  • For this PT, as for all those in the Progetto Trieste – Mycotoxins line, it is possible to send 2 sets of results and thus evaluate 2 laboratory technicians, or two different methodologies, with a single subscription.
  • The assigned value is derived only from quantitative confirmatory results. Results from screening methods are evaluated with dedicated criteria.
  • The cost is only 290.00€ for participation with confirmatory methods.

If you want to see more details about this or other PTs, such as the schedule, prices… go to this page to download the entire programme.

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