31st DGF Proficiency Test 2025

38 parameters can be tested this year.

Each laboratory may choose an individual set of parameters from the list below. The execution and the evaluation of the laboratory proficiency test are carried out according to the internationally recognized recommendations „Proficiency Testing of Laboratories“ of Codex Alimentarius and ISO.

List of parameters:

Quality:
1. Acid value (Free Fatty Acids)
2. Peroxid value
3. Anisidine value
4. Di- and Polymerized Triacylglycerols Parameter of interest: Di-, tri- and oligomeric triacylglycerols = Sum of dimeric, trimeric and oligomeric tricylglycerols
5. Total polar compounds
6. Tocopherols (alpha- Tocopherol, beta-Tocopherol, gamma- Tocopherol and delta- Tocopherol, composition and amount)
7. Lovibond Colour Index (yellow and red)
8. CIELAB Colour Index
9. Gardner Colour Index
10. Phosphorus
11. Chromium
12. Copper
13. Iron
14. Lead
15. Nickel
16. Smoke point
17. Water (Karl Fischer)
18. Hexanal

Identity:
19. Iodine value
20. Saponification value
21. Butyric acid, quantitative
22. FAME composition
23. Triacylglycerol composition (GC-FID)
24. Sterol composition and amount

Olive oil and minor compounds:
25. Stigmastadiene
26. Alkyl esters (Methyl esters (C16 and C18) and Ethyl esters (C16 and C18))
27. Pyropheophytin A
28. Isomeric Diglycerides
29. K-Values (UV Absorption K232, K270)

Organic Contaminants
30. PAH (the most important four acc.to EFSA)
31. Mineral Oil Hydrocarbons
32. 2-/3-MCPD/Glycidol
33. Phthalates
34. Hexane Isomers, Benzene, Toluene, Ethylbenzene, Xylene
35. Antioxidants

Physical properties
36. Refractive Index (20 °C)
37. Density (20/20)
38. Rancimat (120 °C, 10 L/h)

Matrix
Sample A: vegetable oil mix, sample B: olive oil and sample, C: used deep-frying oil.
(150 g each, can be doubled on request)

Participation Fee:
450 Euro + VAT
(a reduced fee of 400 Euro applies for DGF corporate members).

Double amount of samples: add 70 Euro

Shipping of Samples:
add 10 Euro for Germany, 40 Euro for Europe and 100 Euro for World

Registration:
Registration for: 31st DGF Proficiency Test

Deadlines:
Registration: 02.06.2025
Dispatch of samples: 01.07.2025
Deadline of reports: 31.10.2025

For further information please contact:
(Administration)
Deutsche Gesellschaft für Fettwissenschaft
P.O. Box 90 04 40, 60486 Frankfurt/Main, Germany
Phone +49 (0) 69- 7917 533, Fax +49 (0) 69- 7917 564
E-Mail schmitt@dgfett.de
or
(Scientific questions)
Dr. Ludger Brühl (DGF division „Analysis, Quality and Product Safety“)
E-Mail: ludger.bruehl@mri.bund.de