Homogeneity and stability of samples used for proficiency testing in enumeration of coagulase positive Staphylococci

• Autorzy: Korpysa-Dzirba W. , Rola J. G. , Osek J.
• Języki publikacji: EN

Abstrakty

EN

This study describes preparation of test samples composed of freeze-dried strain of S. aureus and powdered milk as a matrix. In the first part of the study, the number of S. aureus cells freeze-dried in skim milk or horse serum were compared at two levels of contamination (10⁴ and 10⁵ cfu g⁻¹). The analysis of the samples was performed three times within a week. The preliminary results showed that the samples composed of S. aureus freeze-dried in horse serum were more stable and homogeneous than those prepared with skim milk. These results were further confirmed after analysing a higher number of such samples. Therefore, this procedure was then chosen for preparation of the samples for proficiency tests (PTs). Homogeneity and stability of these samples were checked according to ISO 13528. The results obtained showed that the samples met the criteria of stability and homogeneity required for PTs and were used in PT for enumeration of S. aureus in powdered milk.

• Wydawca: -
• Czasopismo: Bulletin of the Veterinary Institute in Puławy
• Rocznik: 2012
• Tom: 56
• Numer: 4
• Opis fizyczny: p.559-562,ref.

Twórcy

autor

Korpysa-Dzirba W.

• Department of Hygiene of Food of Animal Origin National Veterinary Research Institute, 24-100 Pulawy, Poland

autor

Rola J. G.

• Department of Hygiene of Food of Animal Origin National Veterinary Research Institute, 24-100 Pulawy, Poland

autor

Osek J.

• Department of Hygiene of Food of Animal Origin National Veterinary Research Institute, 24-100 Pulawy, Poland

Bibliografia

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• 3. ISO/IEC 17043:2010: Conformity assessment - General requirements for proficiency testing. International Standard Organization, Geneva 2010.
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