AS 4659.2:2015 pdf free download – Guide to determining the equivalence of food microbiology test methods Part 2: Quantitative tests

AS 4659.2:2015 pdf free download – Guide to determining the equivalence of food microbiology test methods Part 2: Quantitative tests.
3.6 Reference method
The Australian Standard method against which the alternate method will be compared.
3.7 Target organism
The genus, species, antigenically, toxicologically or physiologically defined group of
organisms which the reference method is designed to detect.
4.1 Define the equisalence determination
The equivalence determination should be defined in terms of the following:
(a) The target organism’s genus. species. aerotype. etc.
(h) The matrix under examination; the food and the characteristics that definc it—the matrix should be detined in terms of characteristics such as pH. solids level, season of production, brand name, water activity, presence and composition of preservatives etc. depending upon the nature of the matrix.
NOTF: When determining equivalence of an alternate method thc lahiiraiory should select the matrices to hc included in thc evaluation from thosc within the scope of the standard method. This Standard is not intended for the validation of matrices outside of the scope of either the alternate method or the standard method. Rcterencc should be made to standard texts and the literature to support the choices of matrices. The choice should take into account the range of sample.s tested by the laboratory and the etTects that the natural variation in significant parameters may have on the detection of the target organism
(c) The alternate method precisely defined by reference to a publication, manufacwrer’s instructions and any optional procedures employed or deviation from the published method.
(d) The reference method—including the specitication optional steps.
For example, the validation of the use of XYZ agar as an alternative to Baird Parker agar in the AS 5013.12.1 method for the enumeration of coagulase positive staphylococci, from custards containing spices and tiavours and a pH greater than 4.5.
(e) Steps of methods which are to be compared, tor example, the alternate method may completely replace the reference method or only a section of the reference method.
(f) The range of colony forming units for which the alternate method is deemed equivalent.
4.2 Define the conditions of the equlsalence determination
The conditions of the equivalence determination should be defined in terms of the following:
(a) The laboratory where testing is performed.
(bf Controls observed by the laboratory during testing, for example controls on the environment of the laboratory, prevention of cross contamination, controls on media and reagents, calibration of equipment, etc. where these factors are considered critical to the success method.
(c) The staff performing the tests (experience, qualifications. etc.).
(d) The starting and finishing dates of the tests.
(c) The batch numbers of media, reagents, etc. used.
NOTli: This information is defined for the purpose of reporting on thc equivalcncc determination and recording factors which may hn e some bearing on the results obtained. These factors do not necessarily affect the veracity of the study or its applicability in other laboratories.
NOTE: Thcrc arc a number of other statistical techniques e.g. non-parametric techniques) that may be helpful in describing the relationship between the results produced by the two methods. Computer-based statistical methods may be used.
The report should contain the following information:
(a) All details necessary for identification of sample types.
(b) Reference to this Standard (i.e. AS 4659.2) and other appropriate Australian Standards.
Reference to the alternate method.
The range of counts, food matrix and season of production (where applicable) for which the validation tests have been performed.
(e) The results obtained.
(f) Date of testing.
(g) Any circumstances that may have influenced the result.