AS 4659.1:2015 pdf – Guide to determining the equivalence of food microbiology test methods Part 1: Qualitative tests

AS 4659.1:2015 pdf – Guide to determining the equivalence of food microbiology test methods Part 1: Qualitative tests.
4.2 Define the condhions of the equisalence determination
The conditions el the equivalence determination should be defined in terms of the
following:
(a) The laboratory where testing is performed.
(b） Controls observed by the laboratory during testing, for example, controls on the environment of the laboratory. prevention of cross examination, controls on media and reagents, calibration of equipment. etc. whcre these l’actors are considered critical to the success of either method,
(c) The staf performing the tests (experience, qualification and the like).
(d) The starling and finishing dates of’ the tests.
(c) The hatch numbers of media. reagents. etc. used.
NOTE: flits informtion is defined for the purpose of reporting on the equisalence determination and recording factors which may base smile hearing on thc results obtained. These factors do not necessarily affect thc seracity of the study.
4.3 Select test organisms
At least five strains of the target organism should be selected. The reference culture prescribed in the Australian Standard method as a positive control should he one of the list strains. The other strains may be selected from the following list (in order of preference):
(a) Strains of the target organism isolated by the laboratory from previous samples of the matrix under examination.
(b) Straitis of the target Organism isolated by reference laboratories or industry sources as representative of the strains found in the type of matrix under examination.
(c) Strains of the target organism held by culture collections.
The strains selccted should encompass the variation that may be expected to he found within the target organism in the matrix under examination.
The identity of the strains chosen should be determined by appropriate means (e.g., biochemical, physiological. serological or molecular) before performing further work. Consultation with a rckrence laboratory or an expert may be neccssary The source and identity of the strains should be recorded.
NOTE: It is possiblc. by the selection of tCst strains, to bias the results of the study. Care should be taken to select representative strains that do not possess characteristics that are likely to lead to a biased result being obtained.
4.4 Select samples of the mairts
Five typical amplc of the matrix should be selected. They should represent as far as possible the range of variation tbund within the defined matris. The choice of samples will depend upon the matrix, but may consist of samples from hatches with high or low background contamination, or samples with different pH values, fat, protein or moisture levels. The aim of’ the selection is to choose samples which will represent the range of variation expected to he found in the defined matrix
‘the significant characteristics of the product should be measured and the results recorded.