This document specifies requirements and gives guidance for the estimation and expression of measurement uncertainty (MU) associated with quantitative results in microbiology of the food chain.<\/p>\n
It is applicable to the quantitative analysis of:<\/p>\n
products intended for human consumption or the feeding of animals;<\/p>\n<\/li>\n
environmental samples in the area of food production and food handling;<\/p>\n<\/li>\n
samples at the stage of primary production.<\/p>\n<\/li>\n<\/ul>\n
The quantitative analysis is typically carried out by enumeration of microorganisms using a colony-count technique. This document is also generally applicable to other quantitative analyses, including:<\/p>\n
most probable number (MPN) techniques;<\/p>\n<\/li>\n
instrumental methods, such as impediometry, adenosine triphosphate (ATP) and flow cytometry;<\/p>\n<\/li>\n
molecular methods, such as methods based on quantitative polymerase chain reaction (qPCR).<\/p>\n<\/li>\n<\/ul>\n
The uncertainty estimated by this document does not include systematic effects (bias).<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 2<\/td>\n | undefined <\/td>\n<\/tr>\n | ||||||
| 4<\/td>\n | European foreword Endorsement notice <\/td>\n<\/tr>\n | ||||||
| 7<\/td>\n | Foreword <\/td>\n<\/tr>\n | ||||||
| 8<\/td>\n | Introduction <\/td>\n<\/tr>\n | ||||||
| 9<\/td>\n | 1 Scope 2 Normative references 3 Terms, definitions and symbols 3.1 Terms and definitions <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | 3.2 Symbols <\/td>\n<\/tr>\n | ||||||
| 13<\/td>\n | 4 General considerations <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | 5 Technical uncertainty 5.1 Identification of main sources of uncertainty 5.1.1 General aspects <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 5.1.2 Sampling uncertainty 5.1.3 Bias 5.1.4 Critical factors <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 5.2 Estimation of technical uncertainty 5.2.1 General aspects 5.2.2 Reproducibility standard deviation derived from intralaboratory experiments, sIR <\/td>\n<\/tr>\n | ||||||
| 21<\/td>\n | 5.2.3 Reproducibility standard deviation derived from interlaboratory studies <\/td>\n<\/tr>\n | ||||||
| 22<\/td>\n | 6 Matrix uncertainty 6.1 General aspects <\/td>\n<\/tr>\n | ||||||
| 23<\/td>\n | 6.2 Case of homogeneous laboratory (or test) sample 6.3 Multiple test portions from laboratory samples <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | 6.4 Known characteristic of the matrix <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | 7 Distributional uncertainties 7.1 General aspects 7.2 Colony-count technique \u2014 Poisson uncertainty 7.3 Colony-count technique \u2014 Confirmation uncertainty <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | 7.4 Most probable number uncertainty <\/td>\n<\/tr>\n | ||||||
| 27<\/td>\n | 8 Combined and expanded uncertainty 8.1 Combined standard uncertainty 8.1.1 General considerations 8.1.2 Combined standard uncertainty based on separate technical, matrix, and distributional standard uncertainties <\/td>\n<\/tr>\n | ||||||
| 28<\/td>\n | 8.1.3 Combined standard uncertainty based on reproducibility standard deviation alone 8.2 Expanded uncertainty 8.3 Worked examples 8.3.1 Example 1 \u2014 Technical, matrix and Poisson components of uncertainty 8.3.2 Example 2 \u2014 Poisson component negligible <\/td>\n<\/tr>\n | ||||||
| 29<\/td>\n | 8.3.3 Example 3 \u2014 Poisson, matrix and confirmation components 8.3.4 Example 4 \u2014 Technical, matrix and most probable number components <\/td>\n<\/tr>\n | ||||||
| 30<\/td>\n | 9 Expression of measurement uncertainty in the test reports 9.1 General aspects <\/td>\n<\/tr>\n | ||||||
| 31<\/td>\n | 9.2 Results below the limit of quantification 9.2.1 General aspects 9.2.2 Example <\/td>\n<\/tr>\n | ||||||
| 33<\/td>\n | Annex A (informative) Calculation of standard deviations with two or more than two test portions (intralaboratory reproducibility standard deviation and matrix uncertainty standard deviation) <\/td>\n<\/tr>\n | ||||||
| 38<\/td>\n | Annex B (informative) Matrix effect and matrix uncertainty <\/td>\n<\/tr>\n | ||||||
| 40<\/td>\n | Annex C (informative) Intrinsic variability (standard uncertainty) of most probable number estimates <\/td>\n<\/tr>\n | ||||||
| 42<\/td>\n | Annex D (informative) Correction of experimental standard deviations for unwanted uncertainty components <\/td>\n<\/tr>\n | ||||||
| 45<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Microbiology of the food chain. Estimation of measurement uncertainty for quantitative determinations<\/b><\/p>\n |