AS 5013.21:2017 pdf free.Food microbiology- Meat and meat products Part 21: Enumeration of presumptive Pseudomonas spp.
6.7 Total-delivery pipettes, sterile, of nominal capacity 1 ml and graduated in 0,1 ml divisions,
ISO 835111 class A, or automatic pipettes, ISO 8655-2121, with use of sterile tips.
6.8 Petri dishes, made of glass or plastic, of diameter 90 mm to 100 mm.
6.9 Spreaders, made of glass or plastic, e.g. hockey sticks made from a glass rod of approximately
3,5 mm diameter and 200 mm length, bent at right angles about 30 mm from one end and with the cut
ends annealed.
7 Sampling
Sampling is not part of the method specified in this International Standard. If there is no specific International Standard dealing with sampling of the product concerned, it is recommended that the interested parties come to an agreement on this subject.
It is important that the laboratory receive a sample which is truly representative and which has not been damaged or changed during transport or storage (see 150 7218).
8 Preparation of test sample
Prepare the test sample in accordance with ISO 6887-1 and ISO 6887-2 and/or the specific International Standard appropriate to the product concerned. If there is no specific International Standard, it is recommended that the parties concerned come to an agreement on this subject.
9 Procedure
9.1 Test portion, initial suspension and dilutions
Prepare the initial suspension and dilutions in accordance with ISO 6887-2.
9.2 Inoculation and incubation
9.2.1 In accordance with ISO 7218, one plate per dilution shall be used with at least two successive dilutions. If only one dilution is performed, then two plates shall be used.
9.2.2 Take one CFC agar plate (5.3.4). Transfer, by means of a pipette (Z), 0,1 ml of the initial suspension on to the plate.
Take another CFC agar plate. Transfer, by means of another sterile pipette, 0,1 ml of the first decimal dilution of the initial suspension on to the plate.
Repeat these operations with subsequent dilutions, using a clean sterile pipette for each decimal dilution.
9.2.3 Spread the liquid over the surface of the agar plate with a sterile spreader (f9) until the surface is completely dry.
9.2.4 Incubate the dishes prepared in this way, with their lids downwards, in an incubator (&Z) at
25°C± 1°Cfor44h±4h.
9.3 Counting and selection of colonies
After the specified incubation period, count the colonies on each plate and retain plates containing less than 150 colonies.
Randomly select five colonies, including all colony types, from each retained plate for confirmation (9A).AS 5013.21 pdf download.