1、BRITISH STANDARD BS EN ISO 11290-1:1996 +A1:2004 BS 5763-18:1997 Incorporating corrigendum September 2009 and January 2010 Microbiology of food and animal feeding stuffs Horizontal method for the detection and enumeration of Listeria monocytogenes Part 1: Detection method ICS 07.100.30BS EN ISO 1129
2、0-1:1996+A1:2004 This British Standard was published under the authority of the Standards Board and comes into effect on 15 May 1997 BSI 2010 ISBN 978 0 580 70397 3 National foreword This British Standard is the UK implementation of EN ISO 11290-1:1996 +A1:2004. It is identical with ISO 11290-1:1996
3、, incorporating amendment 1:2004. Together with BS EN ISO 11290-2:1998+A1:2004, it supersedes BS 4285-3.15:1993 (ISO 10560:1993) which is withdrawn. The start and finish of text introduced or altered by amendment is indicated in the text by tags . Tags indicating changes to ISO text carry the number
4、 of the ISO amendment. For example, text altered by ISO amendment 1 is indicated by !“. The UK participation in its preparation was entrusted to Technical Committee AW/9, Microbiology. A list of organizations represented on this committee can be obtained on request to its secretary. This publication
5、 does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations. Amendments/corrigenda issued since publication Amd. No. Date Comments 15393 22 November 2004 I
6、mplementation of ISO amendment 1:2004 with CEN endorsement A1:2004 30 September 2009 Addition of supersession sentence in the national foreword, and alignment of BSI and CEN publication dates 31 January 2010 Correction to formatting error on CEN forward pageEUROPEAN STANDARD NORME EUROPENNE EUROPISC
7、HE NORM EN ISO 11290-1:1996+A1 October 2004 ICS 07.100.30 Descriptors: See ISO document English version Microbiology of food and animal feeding stuffs Horizontal method for the detection and enumeration of Listeria monocytogenes Part 1: Detection method (ISO 11290-1:1996 + A1:2004) Microbiologie des
8、 aliments Mthode horizontale pour la recherche et le dnombrement de Listeria monocytogenes Partie 1: Mthode de recherche (ISO 11290-1:1996) Mikrobiologie von Lebensmitteln und Futtermitteln Horizontales Verfahren fr den Nachweis und die Zhlung von Listeria monocytogenes Teil 1: Nachweisverfahren (IS
9、O 11290-1:1996 + A1:2004) This European Standard was approved by CEN on 1996-11-15; amendment A1 was approved by CEN on 04-09-30. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standa
10、rd without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. The European Standards exist in three official versions (English, French, German). A version in any other lang
11、uage made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
12、Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung
13、Central Secretariat: rue de Stassart 36, B-1050 Brussels 1996 Copyright reserved to CEN membersRef. No. EN ISO 11290-1:1996 EForeword The text of the International Standard ISO 11290-1:1996 has been prepared by Technical Committee ISO/TC 34, Agricultural food products, in collaboration with Technica
14、l Committee CEN/TC 275, Food analysis Horizontal methods, the Secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 1997, and conflicting national standards sha
15、ll be withdrawn at the latest by June 1997. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembou
16、rg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of the International Standard ISO 11290-1:1996 was approved by CEN as a European Standard without any modification. Foreword to amendment A1 This document (EN ISO 11290-1:1996/A1:2004) h
17、as been prepared by Technical Committee ISO/TC 34, Agricultural food products, in collaboration with Technical Committee CEN/TC 275, Food analysis Horizontal methods, the Secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publicati
18、on of an identical text or by endorsement, at the latest by April 2005, and conflicting national standards shall be withdrawn at the latest by April 2005. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this Eu
19、ropean Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorse
20、ment notice The text of ISO 11290-1:1996 has been approved by CEN as EN ISO 11290-1:1996/A1:2004 without any modifications. BS EN ISO 11290-1:1996+A1:2004 EN ISO 11290-1:1996+A1:2004ii Contents Page Introduction iv 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Principle 1 5 Culture media and
21、reagents 2 6 Apparatus and glassware 3 7 Sampling 4 8 Preparation of test sample 4 9 Procedure 4 10 Expression of results 8 11 Precision of the method 8 12 Test report 9 Annex A (normative) Diagram of procedure 10 Annex B (normative) Composition and preparation of culture media and reagents 10 Annex
22、 C (informative) Henry illumination test 20 Figure 1 Inoculation and interpretation of CAMP test plates 6 Figure C.1 Examination of plates for suspect colonies 21 Table 1 Reactions for the identification of Listeria spp. 7 Descriptors: Agricultural products, food, food products, animal feeding produ
23、cts, microbiological analysis, detection, bacteria, listeria. BS EN ISO 11290-1:1996+A1:2004 EN ISO 11290-1:1996+A1:2004iv Introduction Because of the large variety of food and feed products, this horizontal method may not be appropriate in every detail for certain products for which it may be neces
24、sary to use different or specific methods. Nevertheless, in all cases, every attempt should be made to apply this horizontal method as far as possible and that deviations from this will only be made if absolutely necessary for justified technical reasons. When this part of ISO 11290 is next reviewed
25、, account will be taken of all information then available regarding the extent to which this horizontal method has been followed and the reasons for deviations from it in the case of particular products. The harmonization of test methods cannot be immediate, and for certain groups of products Intern
26、ational Standards and/or national standards may already exist that do not comply with this horizontal method. It is hoped that when such standards are reviewed they will be changed to comply with this part of ISO 11290 so that eventually the only remaining departures from this horizontal method will
27、 be those necessary for well-established technical reasons. BS EN ISO 11290-1:1996+A1:2004 EN ISO 11290-1:1996+A1:20041 WARNING In order to safeguard the health of laboratory personnel, it is strongly recommended that tests for detecting Listeria monocytogenes are undertaken in properly equipped lab
28、oratories, under the control of a skilled microbiologist, and that great care is taken in the disposal of all incubated materials. In particular, it is strongly recommended that pregnant personnel do not manipulate cultures of L. monocytogenes. 1 Scope This part of ISO 11290 specifies a horizontal m
29、ethod for the detection of Listeria monocytogenes. Subject to the limitations discussed in the introduction, this part of ISO 11290 is applicable to products intended for human consumption or animal feeding. 2 Normative references The following standards contain provisions which, through reference i
30、n this text, constitute provisions of this part of ISO 11290. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO 11290 are encouraged to investigate the possibility of applying the most recent edit
31、ions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 6887:1983, Microbiology General guidance for the preparation of dilutions for microbiological examination. ISO 7218:1996, Microbiology of food and animal feeding stuffs Ge
32、neral rules for microbiological examinations. 3 Definitions For the purposes of this part of ISO 11290, the following definitions apply. 3.1 Listeria monocytogenes microorganisms which form typical colonies on solid selective media and which display the morphological, physiological and biochemical c
33、haracteristics described when tests are carried out in accordance with this part of ISO 11290 3.2 detection of Listeria monocytogenes determination of the presence or absence of these microorganisms, in a given mass or volume of product, when tests are carried out in accordance with this part of ISO
34、 11290 4 Principle Within the limits of this part of ISO 11290, the detection of L. monocytogenes necessitates four successive stages (see Annex A for a flowchart). NOTE 1 Listeria spp. may be present in small numbers and are often accompanied by considerably larger numbers of other genera, therefor
35、e selective enrichment is necessary. It is also necessary to detect injured Listeria spp. and the primary selective enrichment medium, with reduced inhibitor concentration, fulfils at least part of this function. 4.1 Primary enrichment in a selective liquid enrichment medium with reduced concentrati
36、on of selective agents (half Fraser broth) Inoculation of a selective primary enrichment medium containing one volume of lithium chloride and half a volume of both acriflavine and nalidixic acid (half Fraser broth), which is also used as a dilution fluid for the test portion (9.1). Incubation of the
37、 test portion at 30 C for 24 h. BS EN ISO 11290-1:1996+A1:2004 EN ISO 11290-1:1996+A1:20042 4.2 Secondary enrichment with a selective liquid enrichment medium with full concentration of selective agents (Fraser broth) Inoculation of full-strength secondary liquid enrichment medium (Fraser broth) wit
38、h a culture obtained from 4.1. Incubation of the Fraser broth at 35 C or 37 C for 48 h. !4.3 Plating out and identification From the cultures obtained in 4.1 and 4.2, plating out on the two selective solid media: a) Agar Listeria according to Ottaviani and Agosti (ALOA 1) ) (see Reference 1 and B.3)
39、; b) any other solid selective medium at the choice of the laboratory complementary to Agar Listeria according to Ottaviani and Agosti, such as Oxford or PALCAM. Incubation of the Agar Listeria according to Ottaviani and Agosti at 37 C 1 C and examination after 24 h 3 h, and if necessary after a fur
40、ther 24 h 3 h, to check for the presence of characteristic colonies which are presumed to be L. monocytogenes. Incubation of the 2nd selective medium at the appropriate temperature and examination after the appropriate time.“ 4.4 Confirmation Subculturing of the colonies of presumptive L. monocytoge
41、nes, plated out as described in 4.3, and confirmation by means of appropriate morphological, physiological and biochemical tests. 5 Culture media and reagents 5.1 General For current laboratory practice, see ISO 7218. NOTE 2 Because of the large number of culture media and reagents, it has been cons
42、idered preferable, for clarity of the text, to give their composition and preparation in Annex B. 5.2 Selective primary enrichment medium: Fraser broth with reduced concentration of selective agents (half Fraser broth) See Clause B.1. 5.3 Selective secondary enrichment medium with full concentration
43、 of selective agents (Fraser broth) See Clause B.2. 5.4 Selective solid plating-out media !5.4.1 First medium: Agar Listeria according to Ottaviani and Agosti (ALOA 1) ) 1 See B.3. 5.4.2 Second medium The choice of the second medium is left to the discretion of the testing laboratory. If a commercia
44、l medium is used, the manufacturers instructions shall be precisely followed regarding its preparation for use.“ 5.5 Solid culture medium: Tryptone soya yeast extract agar (TSYEA) See Clause B.5. 5.6 Liquid culture medium: Tryptone soya yeast extract broth (TSYEB) See Clause B.6. 5.7 Sheep blood aga
45、r See Clause B.7. 1) ALOA is an example of a suitable medium available commercially. This information is given for the convenience of users of this part of ISO 11290 and does not constitute an endorsement by ISO of this product. The use of other media with the same formulation is allowed. BS EN ISO
46、11290-1:1996+A1:2004 EN ISO 11290-1:1996+A1:20043 5.8 Carbohydrate utilization broth (rhamnose and xylose) See Clause B.8. 5.9 Motility agar (optional) See Clause B.9. 5.10 CAMP (Christie, Atkins, Munch-Petersen) medium and test strains See Clause B.10. 5.11 Hydrogen peroxide solution See Clause B.1
47、1. 5.12 Phosphate-buffered saline (PBS) See Clause B.12. 6 Apparatus and glassware Usual microbiological equipment (see ISO 7218) and, in particular, the following. 6.1 Apparatus for dry sterilization (oven) or wet sterilization (autoclave) See ISO 7218. 6.2 Drying cabinet or incubator, capable of b
48、eing maintained at between 25 C 1 C and 50 C 1 C. 6.3 Incubators, for maintaining the inoculated media, plates and tubes within the following temperature ranges: a) 25 C 1 C; b) 30 C 1 C; and c) 35 C 1 C or 37 C 1 C. 6.4 Water bath, capable of being maintained at 47 C 2 C. 6.5 Loops, of platinum/iri
49、dium or nickel/chromium, approximately 3 mm in diameter, and wires of the same material, or hockey-stick-shaped glass rods or single-use loops. 6.6 pH-meter, capable of being read to the nearest 0,01 pH unit at 25 C, enabling measurements to be made which are accurate to 0,1 pH unit. 6.7 Test tubes or flasks, of appropriate capacity, for sterilization and storage of culture media and incubation of liquid media. 6.8 Measuring cylinders, of capacity 50 ml to 1 000 ml, for preparat
