SIST-TS CEN/TS 15568:2007

SLOVENSKI STANDARD
SIST-TS CEN/TS 15568:2007
01-marec-2007
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Foodstuffs - Methods of analysis for the detection of genetically modified organisms and
derived products - Sampling strategies
Lebensmittel - Verfahren zum Nachweis von gentechnisch modifizierten Organismen und
ihren Produkten - Probenahmestrategien
Produits alimentaires - Méthodes d'analyse pour la détection des organismes
génétiquement modifiés et des produits dérivés - Stratégies d'échantillonnage
Ta slovenski standard je istoveten z: CEN/TS 15568:2006
ICS:
67.050 Splošne preskusne in General methods of tests and
analizne metode za živilske analysis for food products
proizvode
SIST-TS CEN/TS 15568:2007 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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TECHNICAL SPECIFICATION
CEN/TS 15568
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
December 2006
ICS 67.050

English Version
Foodstuffs - Methods of analysis for the detection of genetically
modified organisms and derived products - Sampling strategies
Produits alimentaires - Méthodes d'analyse pour la Lebensmittel - Verfahren zum Nachweis von gentechnisch
détection des organismes génétiquement modifiés et des modifizierten Organismen und ihren Produkten -
produits dérivés - Stratégies d'échantillonnage Probenahmestrategien
This Technical Specification (CEN/TS) was approved by CEN on 7 November 2006 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 15568:2006: E
worldwide for CEN national Members.

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CEN/TS 15568:2006 (E)
Contents Page
Foreword.3
Introduction .4
1 Scope .5
2 Normative references .5
3 Terms and definitions .5
4 Principle.6
5 Apparatus and equipment .7
6 Sampling of non-packed food products.7
7 Sampling of pre-packed units .9
8 Preparation of the analytical sample and the test portion .10
9 Packaging and labelling of laboratory samples .10
10 Dispatch of laboratory samples .11
11 Sampling report .11
Annex A (informative) Laboratory sample sizes of different cereals and oilseeds.13
Annex B (informative) Sampling scheme for consignments of more than 100 bags according to
ISO 13690.14
Annex C (informative) Estimation of the number of particles in 100 mg test portions after ultra-
centrifugal milling.15
Bibliography .16

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CEN/TS 15568:2006 (E)
Foreword
This document (CEN/TS 15568:2006) has been prepared by Technical Committee CEN/TC 275 “Food
analysis - Horizontal methods”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
NOTE This document has been submitted to the Enquiry under reference number prEN 21568.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden,
Switzerland and the United Kingdom.
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CEN/TS 15568:2006 (E)
Introduction
Correct sampling is an operation that requires the most careful attention. Emphasis should be laid on the
necessity of obtaining a representative sample of the goods under investigation.
If ad-hoc sampling of food products is undertaken without applying a sampling strategy and without
considering the lot specific properties, the analytical result is only valid for the sample that has been analysed.
It is not possible to extend the result to the rest of the lot.
By applying sampling strategies to assess the level of compliance of a given lot of products, a certain number
of samples is taken, and the result of the analysis can be extended to the whole lot. The use of sampling
strategies is the only effective way to make correct statements about the nature, in this case the GMO-content,
of the product tested.
This Technical Specification has been established for food products, but could also be applied to other
products, e.g. animal feed and plant samples from the environment.
NOTE In certain areas there are widely recognised trade associations which specify rules for the sampling strategies
to be used in contracts under their auspices. In no case will this Technical Specification override the rules laid down in
such contracts.
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CEN/TS 15568:2006 (E)
1 Scope
This Technical Specification gives guidance for setting up valid sampling strategies for food products that are
to be analysed for the presence of genetically modified organisms and derived products.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN ISO 21569, Foodstuffs — Methods of analysis for the detection of genetically modified organisms and
derived products — Qualitative nucleic acid based methods (ISO 21569:2005)
EN ISO 21570, Foodstuffs — Methods of analysis for the detection of genetically modified organisms and
derived products — Quantitative nucleic acid based methods (ISO 21570:2005)
EN ISO 21571, Foodstuffs — Methods of analysis for the detection of genetically modified organisms and
derived products — Nucleic acid extraction (ISO 21571:2005)
EN ISO 21572, Foodstuffs — Methods for the detection of genetically modified organisms and derived
products — Protein based methods (ISO 21572:2004)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Consignment
quantity of some commodity delivered at one time and covered by one set of documents. The consignment
may consist of one or more lots or part(s) of lots
[ISO 7002:1986]
3.2 Lot
stated portion of the consignment to be tested for presence of GMO
3.3 Increment
quantity of material taken at one time from a larger body of material
NOTE Increments may be tested individually aiming at estimation of the variation of any characteristic throughout a
lot (or between lots).
[ISO 7002:1986]
3.4 Item
actual or conventional object (a defined quantity) on which a set of observations may be made
[ISO 7002:1986]
3.5 Sample
one or more items (or a portion of material) selected in a prescribed or systematic manner from a lot
NOTE It is intended to provide information representative of the lot, and, possibly, to serve as a basis for decision on
the lot.
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CEN/TS 15568:2006 (E)
3.6 File increment sample
increment that is retained for a specific period of time for further analysis
3.7 Bulk sample
composite of the increments taken from a lot
3.8 Laboratory sample
sample as prepared for sending to the laboratory and intended for inspection or testing
[ISO 7002:1986]
3.9 Test portion
sample, as prepared for testing or analysis, the whole quantity being used for analysis or testing at one time
[ISO 3534-1:2006]
3.10 Lot size
number of items or quantity of material constituting the lot
[ISO 7002:1986]
3.11 Sample size
number of items or quantity of material constituting the sample
[ISO 7002:1986]
3.12 Sample division
process of selecting one or more representative sub-samples from a sample by such means as riffling or
mechanical dividing
3.13 Sampling uncertainty
part of the total estimation uncertainty due to one or several of the following:
- the failing of a sample to accurately represent the lot;
- the random nature of sampling;
- the known and accepted characteristics of the sampling strategy
3.14 Sampling strategy
predetermined procedure for the selection, withdrawal and preparation of samples from a lot to yield the
required information so that a decision can be made regarding the acceptance of the lot
[ISO 7002:1986]
4 Principle
In this Technical Specification sampling is considered to consist of the following steps:
 collection of a sufficient number of increments from a lot to form the bulk sample;
 reduction of the bulk sample to the laboratory sample;
 grinding the laboratory sample to the appropriate particle size and homogenisation.
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CEN/TS 15568:2006 (E)
Samples shall be representative of the lots from which they are taken. Therefore, as the composition of a lot is
seldom uniform, a sufficient number of increments shall be taken and carefully mixed, thus giving a bulk
sample from which the laboratory sample is obtained by successive divisions or otherwise.
If it is necessary to determine the sampling uncertainty, file increment samples should be kept for further
analysis.
Appropriate measures shall be taken to avoid any alteration in the composition of the samples.
5 Apparatus and equipment
Many different types of sampling instruments or equipment are available. Equipment should be chosen as
appropriate for the food products to be sampled and the quantity and containers involved. Examples of
sampling instruments are given in e.g. ISO 13690 and ISO 6644. Special care is necessary to ensure that all
sampling apparatus is clean to avoid contamination of the material under investigation.
Sampling shall be carried out in such a manner as to protect the samples, the sampling instruments and the
container in which the samples are placed, from adventitious contamination. Special attention shall be paid to
avoid cross-contamination during the sampling procedure between different lots. Material adhering to the
outside of the sampling instrument shall be removed before the contents are discharged.
6 Sampling of non-packed food products
6.1 Statistical principles
Lot distribution properties affect the efficiency of sampling strategies [5]. Where the variable of interest is
randomly distributed within the lot under investigation, the sampling uncertainty can be estimated according to
the binomial distribution [6]. However, in reality, non-packed food product lots may show non-random
distributions [7], and lot heterogeneity should be taken into account when defining sampling procedures
statistically.
This sampling protocol provides a way of estimating the sampling uncertainty associated with the overall GMO
content of a lot without imposing any distribution assumption.
The Standard Deviation (SD) of the increment GMO content estimates may be interpreted as an indicator of
the lot heterogeneity and in highly heterogeneous lots as an indication of the sampling uncertainty. Generally,
the larger the standard deviation, the larger is the sampling uncertainty in highly heterogeneous lots.
6.2 Procedure
6.2.1 General
This protocol is designed to provide an estimate of the GMO content of the lot based on a bulk sample. If an
estimate of the sampling uncertainty is required, 6.2.3 describes a procedure to determine it.
6.2.2 Sampling of increments
Lots should be sampled following the technical principles given in ISO 6644 as described in 6.3 and
ISO 13690 as described in 6.4.
The number of sampling points, where the increments for creating the bulk sample and the file increment
samples are taken is defined according to the lot size. In case of lots from 50 t to 500 t, the size of the bulk
sample should be 0,01 % of the total lot size. In case of lots smaller than 50 t, the size of the bulk sample
should be 5 kg. In case of lots larger than 500 t, the size of the bulk sample should be 50 kg (see Table 1).
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