Appendix

Proceedings of the 21st Meeting Working Group on Prolamin Analysis and Toxicity, September 28-30 2006, Trieste, Italy (Verlag Wissenschaftliche Scripten, Zwickau 2007, 160-164).

PWG gliadin

PWG gliadin has been returned by the Institute for Reference Material and Measurements, Geel, Belgium, to PWG in 2006. It has finally not been accepted as a certified reference material by IRMM. Previous codes given to this material are no longer valid.

Protein content of PWG gliadin was determined by Dr. Herbert Wieser, Deutsche Forschungsanstalt für Lebensmittelchemie, Garching, Germany. Results are shown in Table 1. It can be assumed that residual acetic acid was removed during storage or by modifying.

TABLE 1. Protein content of PWG gliadin

* Van Eckert R, et al. Towards a new gliadin reference material – isolation and characterisation.

J Cer Sci 2006; 43: 331-341.

According to the analysis performed by Dr. Enrique Méndez, CSIC, Cantoblanco, Madrid, Spain, results by PAGE-SDS, R5 Western blot and MALDI-TOF spectrometry do not show differences between the old PWG gliadin and modified PWG gliadin (See Figs. 1-5, Tables 2 and 3).
 

Figure 1.

Analysis of European gliadin (Old and Modified) by MALDI-TOF/MS.

Figure 2.

Analysis of European gliadin (Old) by MALDI-TOF/MS.

Figure 3.

Analysis of European gliadin (Modified) by MALDI-TOF/MS.

Figure 4.

Analysis of Old and Modified European gliadin (ES) by comassie-blue.

Figure 5.

Analysis of Old and Modified European gliadin (ES) by R5 Western blot.

Table 2.

Analysys of European Gliadin Standards (Old and Modified) by MALDI-TOF/MS

Table 3.

Average values of mass signals obtained from MALDI-TOF/MS analysis of Old and Modified European gliadin (ES).