Animal feeding stuffs - Guidelines for sample preparation (ISO 6498:2012)

This International Standard specifies guidelines for the preparation of test samples from laboratory samples of animal feeding stuffs, including pet foods. The guidelines are overruled by special instructions and regulations for sample preparation demanded by specific analysis methods.

Futtermittel - Leitfaden für die Probenvorbereitung (ISO 6498:2012)

Diese Internationale Norm legt einen Leitfaden zur Herstellung von Untersuchungsproben aus Laboratoriums-proben von Tierfuttermitteln, einschließlich Futtermitteln für Heimtiere fest.
ANMERKUNG 1   Der Leitfaden leitet sich am häufigsten von den Richtlinien des AAFCO (en: Association of American Feed Control Officials) (Verband amerikanischer Kontrollbehörden für Futtermittel) ab (siehe Literaturhinweis [7]).
Der Leitfaden wird von speziellen Anweisungen und Vorschriften zur Probenvorbereitung aufgehoben, die durch spezifische Analysenverfahren gefordert werden.
ANMERKUNG 2   Solche Analyseverfahren werden von ISO und CEN entwickelt.
ANMERKUNG 3   Diese Internationale Norm enthält keinen speziellen Leitfaden zur Probenvorbereitung für die mikrobiologische Analyse von Mikroorganismen, wie z. B. Hefen, Bakterien und Schimmelpilze. Trotzdem sind für Mikroorganismen, die als Futtermittelzusätze (Probiotika) verwendet werden, einige wichtige Gesichtspunkte zur Proben¬vorbereitung genannt.

Aliments des animaux - Lignes directrices pour la préparation d'échantillons (ISO 6498:2012)

L'ISO 6498:2012 spécifie des lignes directrices pour la préparation des échantillons pour essai d'aliments pour animaux, y compris les animaux domestiques, à partir des échantillons pour laboratoire.
Les lignes directrices sont annulées par des instructions et des règlements particuliers pour la préparation des échantillons exigés par les méthodes d'analyse spécifiques des aliments pour animaux.

Krma - Smernice za pripravo vzorca (ISO 6498:2012)

Ta mednarodni standard določa smernice za pripravo preskusnih vzorcev iz laboratorijskih vzorcev krme, vključno s hrano za hišne ljubljenčke. Posebne analizne metode vključujejo posebna navodila in predpise, ki se uporabljajo namesto teh smernic.

General Information

Status
Published
Public Enquiry End Date
31-Aug-2009
Publication Date
25-Sep-2012
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
21-Aug-2012
Due Date
26-Oct-2012
Completion Date
26-Sep-2012

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SLOVENSKI STANDARD
SIST EN ISO 6498:2012
01-oktober-2012
Krma - Smernice za pripravo vzorca (ISO 6498:2012)
Animal feeding stuffs - Guidelines for sample preparation (ISO 6498:2012)
Futtermittel - Leitfaden für die Probenvorbereitung (ISO 6498:2012)
Aliments des animaux - Lignes directrices pour la préparation d'échantillons (ISO
6498:2012)
Ta slovenski standard je istoveten z: EN ISO 6498:2012
ICS:
65.120 Krmila Animal feeding stuffs
SIST EN ISO 6498:2012 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 6498:2012

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SIST EN ISO 6498:2012


EUROPEAN STANDARD
EN ISO 6498

NORME EUROPÉENNE

EUROPÄISCHE NORM
June 2012
ICS 65.120
English Version
Animal feeding stuffs - Guidelines for sample preparation (ISO
6498:2012)
Aliments des animaux - Lignes directrices pour la Futtermittel - Leitfaden für die Probenvorbereitung (ISO
préparation des échantillons (ISO 6498:2012) 6498:2012)
This European Standard was approved by CEN on 31 May 2012.

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 standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, 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, Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 6498:2012: E
worldwide for CEN national Members.

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SIST EN ISO 6498:2012
EN ISO 6498:2012 (E)
Contents Page
Foreword .3
2

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SIST EN ISO 6498:2012
EN ISO 6498:2012 (E)
Foreword
This document (EN ISO 6498:2012) has been prepared by Technical Committee CEN/TC 327 “Animal feeding
stuffs - Methods of sampling and analysis", the secretariat of which is held by NEN, in collaboration with
Technical Committee ISO/TC 34 "Food products".
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 December 2012, and conflicting national standards shall be withdrawn
at the latest by December 2012.
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.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, 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, Turkey and the United Kingdom.
3

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SIST EN ISO 6498:2012

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SIST EN ISO 6498:2012
INTERNATIONAL ISO
STANDARD 6498
Third edition
2012-06-01
Corrected version
2012-07-15
Animal feeding stuffs — Guidelines for
sample preparation
Aliments des animaux — Lignes directrices pour la préparation des
échantillons
Reference number
ISO 6498:2012(E)
©
ISO 2012

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Terms and definitions . 1
2.1 Definitions concerning “sample” . 1
2.2 Definitions concerning “parameters” . 2
2.3 Examples of animal feeding stuffs characteristics . 3
2.4 Definitions concerning “sample preparation procedure” . 5
3 Principle . 6
4 Consideration of sample preparation errors . 7
4.1 Subsampling and other errors . 7
4.2 Minimum mass . 8
4.3 Errors associated with division techniques . 9
5 Safety precautions .10
6 Apparatus .10
7 Procedure .12
7.1 General .12
7.2 Sample check .12
7.3 Mass reduction .14
7.4 Particle size reduction .17
7.5 Partial drying .20
7.6 Coarse grinding .22
7.7 Special sample preparation procedures .22
7.8 Storage .22
8 Performance tests (quality control) .22
8.1 General .22
8.2 Performance test for mass reduction (division) .23
8.3 Performance test for particle size reduction (grinding) .24
8.4 Performance test for mixing .25
9 Categories of feeds — Special remarks and flow charts .25
9.1 General .25
9.2 Birdseed .26
9.3 Whole cottonseed .27
9.4 Mineral mix .29
9.5 Dry feeds .29
9.6 Forages including silage, hay, haylage, TMR and byproducts .30
9.7 Oilseeds and high-fat feeds .32
9.8 Large block and molasses block feeds .33
9.9 Liquid feeds .35
9.10 Canned pet food .35
9.11 Semi-moist pet food and dog chews.36
9.12 Premixtures .37
9.13 Range and alfalfa hay pellets .38
9.14 Texturized and sticky feed .39
9.15 Aquatic feeds .40
Annex A (informative) Calculations, examples and tables for minimum mass .42
Bibliography .46
© ISO 2012 – All rights reserved iii

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International
Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 6498 was prepared by the European Committee for Standardization (CEN) Technical Committee TC 327,
Animal feeding stuffs — Methods of sampling and analysis, in collaboration with ISO Technical Committee
TC 34, Food products, Subcommittee SC 10, Animal feeding stuffs, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 6498:1998), which has been technically revised.
This corrected version of ISO 6498:2012 incorporates the following correction: in 7.1, paragraph 4, the phrase
“particle sizes below 4 mm ± 2 mm (4 mm to 6 mm) can be” has been substituted by “particle sizes of 4 mm to
6 mm can be”.
iv © ISO 2012 – All rights reserved

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SIST EN ISO 6498:2012
INTERNATIONAL STANDARD ISO 6498:2012(E)
Animal feeding stuffs — Guidelines for sample preparation
1 Scope
This International Standard specifies guidelines for the preparation of test samples from laboratory samples of
animal feeding stuffs, including pet foods.
NOTE 1 The guidelines mostly derive from those developed by AAFCO (see Reference [7]).
The guidelines are overruled by special instructions and regulations for sample preparation demanded by
specific analysis methods.
NOTE 2 Such analysis methods are developed by ISO and CEN.
NOTE 3 This International Standard does not include special guidelines for sample preparation for microbiological
analysis of microorganisms like yeasts, bacteria and moulds. Nonetheless, for microorganisms which are used as feed
additives (probiotics), some important aspects of sample preparation are addressed.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1 Definitions concerning “sample”
2.1.1
lot
quantity of material that is assumed to be of the same production process and represented by specified
sampling rules
NOTE For the purposes of this International Standard, the rules are those of Commission Regulation (EC)
[3]
No. 152/2009.
2.1.2
laboratory sample
sample as prepared (from the lot) for sending to the laboratory and intended for inspection or testing
2.1.3
test sample
subsample or sample prepared from the laboratory sample and from which test portions will be taken
2.1.4
test portion
quantity of material drawn from the test sample (or from the laboratory sample if both are the same)
2.1.5
reserve sample
material left over from the laboratory sample when divided or subsampled test samples have been taken and
on which no further particle size reduction is done
NOTE If, for example, mycotoxin or genetically modified organism analyses are done on the whole laboratory sample,
then the reserve sample is also reduced to the corresponding particle sizes. The reserve sample should be stored under
conditions maintaining integrity.
© ISO 2012 – All rights reserved 1

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
2.2 Definitions concerning “parameters”
2.2.1
parameter
analyte or constituent or microorganism for which the feeding stuff is to be analysed by microscopic,
microbiological, biological or chemical procedures
2.2.1.1
stable parameter
analyte or constituent or microorganism which does not degrade during sample preparation on common
handling or storage at room temperatures of 20 °C to 25 °C
2.2.1.2
unstable parameter
analyte or constituent or microorganism which degrades during sample preparation on common handling
or storage at room temperatures of 20 °C to 25 °C because they are volatile, degradable, or sensitive to
temperature, light, enzymatic degradation or chemical oxidation
NOTE Stability of parameters in this context refers only to the influence of sample preparation, such as intensive
grinding, and not to a minimum shelf-life specified by producers or on the label, e.g. for a feed (additive).
Table 1 — Classification (in general) of stable or unstable parameters
and reasons for degradation with a view to sample preparation
Reason(s) for
Origin Stable parameters Unstable parameters
degradation/change
(Crude) protein, fat, ash, fibre Moisture Temperature (volatile)
Starch, sugar, lactose Ammonia Temperature (volatile)
Gas production and enzyme- Organic acids (e.g. lactic
soluble organic substance acid, acetic acid, butyric acid, Temperature (volatile)
Nutrients
production in in vitro tests fumaric acid, formic acid)
Air oxidation (can result in
Minerals
Unsaturated fatty acids production of short-chain fatty
(e.g. Ca, P, Mg, Na, K, Cl)
acids)
Trace elements Vitamins Temperature, ultraviolet (UV)
(e.g. Cu, Zn, Mn, Fe, Se, Co) (e.g. vitamin A, C, D, E) light, air oxidation (sensitive)
Amino acids (e.g. lysine, 1,2-Propanediol, ethylene
Temperature (volatile)
methionine, tryptophan) glycol
Feed additives
Temperature (freezing),
Microorganisms like probiotics
Enzymes (e.g. phytases, pressure (sensitive to
(e.g. Saccharomyces
non-starch polysaccharide grinding); moisture/dryness
cerevisiae, Enterococcus
enyzmes) (influences growth of
faecium)
microorganisms)
Mycotoxins (e.g. aflatoxin B ,
1
Mould growth and change
deoxynivalenol, fumonisins,
Heavy metals of mycotoxins possible at
ochratoxin A, T-2 toxin, HT-2
(e.g. As, Pb, Cd, Hg) room temperature; UV light
toxin, zearalenone, ergot
(sensitive – aflatoxin B )
1
Undesirable
alkaloids)
substances
Dioxins and polychlorinated
biphenyls (PCBs) with similar Drugs, antibiotics, pesticides Temperature (sensitive)
effects to dioxins
Hydrocyanic acid Temperature (volatile)
Banned Banned drugs, banned
Proteins of animal origin Temperature (sensitive)
substances antibiotics
Temperature (sensitive),
(Other)
Yeasts, bacteria, moulds dryness, influx of oxygen
Microorganisms
(anaerobiosis)
2 © ISO 2012 – All rights reserved

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
2.3 Examples of animal feeding stuffs characteristics
Some examples of animal feeding stuffs characteristics are given here to assist with the identification and
grouping of a laboratory sample based on the terms and annexes used in these guidelines.
NOTE Definitions of animal feeding stuffs are given in legislation worldwide. Sample definitions from European
directives and, for straight feeds, in an alphabetical list from a German committee are given in References [4][5][6][8].
2.3.1
birdseed
seeds that are intended to feed birds
EXAMPLES Grains and oilseeds.
2.3.2
whole cottonseed
unprocessed cottonseed product, including the hulls, lint, and meat
2.3.3
mineral mix
supplementary feed that mainly consists of mineral ingredients in either granular, bead or small pellet form and
which is free flowing as an entire mix
NOTE Mineral pellets are an agglomerated mineral mix formed by a mechanical process (in general).
2.3.4
dry feeds
feed ingredient or complete animal feed which typically contains a moisture mass fraction of not more than 15 %
NOTE Dry feed pellets are an agglomerated dry feed produced by a mechanical process (in general).
2.3.5
green fodder
edible parts of plants, other than separated grain, that can provide feed for grazing animals or that can be
harvested for feeding, including browse, herbage, and mast
NOTE Generally, the term refers to more digestible material in contrast to less-digestible plant material, known as roughage.
2.3.6
silage
forage preserved in a succulent condition by organic acids produced by anaerobic fermentation of sugars
in the forage
2.3.7
roughage
fibrous, coarsely textured parts of plants
EXAMPLES Stovers, straws, hulls, cobs, and stalks.
2.3.8
hay
aerial portion of grass especially cut and dried for animal feeding
2.3.9
haylage
forage preserved in a succulent condition by organic acids produced by anaerobic fermentation of sugars in
the forage with a moisture mass fraction of about 45 %
© ISO 2012 – All rights reserved 3

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
2.3.10
total mixed ration
TMR
single mixture of all feed ingredients (forages, grains, and supplements) that is supplied to an animal for a 24 h period
NOTE In practice, the 24 h allotment of the mixture may be offered in one or more feedings.
2.3.11
byproduct
product which remains after processes for the production of ingredients from plant material
EXAMPLE Dried distillers grains with solubles (DDGSs) from fermentation.
2.3.12
oilseed
any seed from which oil is extracted
EXAMPLE Sunflower seeds.
2.3.13
large block feed
molasses block feed
agglomerated feed compressed into a solid mass that is cohesive enough to hold its form
NOTE Large block feed weighs over 1 kg, generally about 20 kg. It may be marketed as a mineral block or a
“caramelized” molasses drum, containing various minerals and nutrients. Samples may be received by the laboratory as
large chunks, cores or “sticky clumps”.
2.3.14
liquid feed
feed product not solid and not aeriform
NOTE A liquid feed contains sufficient moisture to flow readily and may contain molasses.
2.3.15
canned pet food
feed product for pets which has been processed, packaged, sealed and sterilized for preservation in cans or
similar containers
2.3.16
semi-moist feed
meat-based feed product for pets or aquatic animals that has been partially dried to prevent microbial
decomposition
NOTE The moisture mass fraction may range from 15 % to 40 %. The product is generally in the form of strips or
cubes and is designed to be stored at room temperature.
2.3.17
dog chew
rawhide bone
meat and skin or peel strip that has been nearly completely dried to a leather-like consistency
2.3.18
premixture
mixture of one or more micro-ingredients with diluent or carrier
NOTE Premixtures are used to facilitate uniform dispersion of the micro-ingredients (e.g. vitamins, probiotics, drugs
or antibiotics) into a final feed.
4 © ISO 2012 – All rights reserved

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
2.3.19
range and alfalfa hay pellet
agglomerated feed formed by compacting and forcing the mix through, for example, square openings by a
mechanical process
3
NOTE The pellets are mostly about 2 cm in diameter and 5 cm in length (volume about 16 cm ) and may contain
molasses; this definition also applies to alfalfa cubes (chopped alfalfa hay) of larger dimensions.
2.3.20
texturized feed
sticky feed
mix of assorted grains and commercial feed (generally pelleted), all of which has been treated with a coating
of, for example, molasses
NOTE Some of the grains may have been steam heated or rolled prior to incorporation into the texturized feed.
2.3.21
aquatic feed
feed which is fed to aquatic animals and which has been mechanically processed into encapsulated pellets,
flakes, crumble, and as packaged sealed powder
2.4 Definitions concerning “sample preparation procedure”
2.4.1
homogeneity
degree to which a property or a constituent is uniformly distributed throughout a quantity of material
NOTE Homogeneity may be considered to have been achieved in a practical sense when the sampling error of the
processed portion is negligible compared to the total error of the measurement system. Since homogeneity depends
on the size of the units under consideration, a mixture of two materials may be inhomogeneous at the molecular or
atomic level, but sufficiently homogeneous at the particulate level. However, uniform visual appearance does not ensure
compositional homogeneity.
2.4.2
partial drying
part of the sample preparation procedure for feedstuff samples with a high moisture content (dry mass fraction
<85 %), in which the sample is carefully dried to allow subsequent sample preparation procedures to be
applied, such as particle size reduction by grinding with a mill
NOTE 1 The partial drying procedure depends on the feeding stuff [e.g. at temperatures below 55 °C to 60 °C for
silages], and on the heat stability of the parameters (e.g. 70 °C ± 10 °C for drugs and antibiotics).
NOTE 2 Samples for microbiological analysis should not be dried (at temperatures above 40 °C).
NOTE 3 Partial drying can also be achieved by a freeze-drying procedure, which is a careful drying process using a
vacuum to allow moisture to evaporate.
2.4.3
coarse grinding
first grinding step of the whole sample when the laboratory sample contains large lumps or when its particle
size is above about 6 mm before mass reduction
NOTE Coarse grinding is a special kind of particle size reduction that ensures homogeneity of the laboratory sample
for subsampling purposes.
2.4.4
mass reduction
part of the sample preparation procedure to reduce the mass of a laboratory sample by dividing or
subsampling it using (stationary or rotary) dividers or fractional (alternate) shovelling, without changing the
consistency of the sample
NOTE After mass reduction, all subsamples should have the same properties as the original laboratory sample.
© ISO 2012 – All rights reserved 5

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
2.4.5
particle size reduction
part of the sample preparation procedure achieved by chopping, crushing, cutting, blending (homogenizing),
macerating, milling (grinding), pressing, pulverizing to obtain a homogeneous test sample for further analysis
NOTE In general, particle size reduction follows the mass reduction step of the sample preparation procedure with
different sieve size options to ensure integrity of the test sample(s).
sampling: choice from lot
sample preparation:
laboratory sample(s) (≥500 g) with:
dry matter < 15 % mass fraction
lumps or big particles (> 6 mm)
dry matter ≥85% mass fraction
partial (or freeze) drying (optionally) coarse grinding
mass reduction (subsampling/splitting) reserve sample
test sample(s) (100 g) for:
particle size reduction
– microscopy
with different sieve-size options
– analysis of stable parameters
(1,0 mm, 0,5 mm, <0,5 mm, no
– analysis of unstable parameters
grinding)
analysis: test portion(s) (0,05 g to 25 g)
Figure 1 — Illustration of definitions concerning “sample”, “substances”
and “sample preparation procedure”
3 Principle
All sample preparation steps depend on the different properties of the feedstuffs and on the parameters to
be analysed. In each case, any special instructions concerning sample preparation in the analysis methods
require consideration.
The guidelines describe the procedure for preparing — from a sample arriving at a laboratory (in general with
a minimum mass of 0,5 kg) — a homogeneous test sample (having a minimum mass of 100 g) with the same
constitution and composition and free from contamination.
6 © ISO 2012 – All rights reserved

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SIST EN ISO 6498:2012
ISO 6498:2012(E)
In some cases, the laboratory sample size can be less than 500 g (i.e. in standards for feed additives), but it
is necessary to follow statutory regulations and, in every case, the sample size should be large enough to be
representative.
In general, the whole laboratory sample is reduced in mass and in particle size to obtain one or more test
samples for the analysis of stable and unstable parameters, for microscopy analysis and for reserve. If the
analysis protocol and the intended proceeding of the reserve sample permit it, the laboratory sample should
preferably be pre-ground completely to an adequate coarse particle size before being reduced further, in order
to ensure homogeneity of the test samples.
From a test portion (0,05 g to 25 g and above) prepared for weighing in the feedstuff analysis, representative
results should be achieved on the laboratory sample and finally on the whole lot from which the sample
...

SLOVENSKI STANDARD
oSIST prEN ISO 6498:2009
01-julij-2009
Krma - Smernice za pripravo vzorca (ISO/DIS 6498:2009)
Animal feeding stuffs - Guidelines for sample preparation (ISO/DIS 6498:2009)
Futtermittel - Leitfaden für die Probenvorbereitung (ISO/DIS 6498:2009)
Aliments des animaux - Lignes directrices pour la préparation d'échantillons (ISO/DIS
6498:2009)
Ta slovenski standard je istoveten z: prEN ISO 6498
ICS:
65.120 Krmila Animal feeding stuffs
oSIST prEN ISO 6498:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 6498:2009

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oSIST prEN ISO 6498:2009
EUROPEAN STANDARD
DRAFT
prEN ISO 6498
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2009
ICS 65.120

English Version
Animal feeding stuffs - Guidelines for sample preparation
(ISO/DIS 6498:2009)
Aliments des animaux - Lignes directrices pour la Futtermittel - Probenvorbereitung (ISO/DIS 6498:2009)
préparation d'échantillons (ISO/DIS 6498:2009)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
CEN/TC 327.
If this draft becomes a European Standard, 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 standard without any alteration.
This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the
same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 6498:2009: E
worldwide for CEN national Members.

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oSIST prEN ISO 6498:2009
prEN ISO 6498:2009 (E)
Contents Page
Foreword .3

2

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oSIST prEN ISO 6498:2009
prEN ISO 6498:2009 (E)
Foreword
This document (prEN ISO 6498:2009) has been prepared by Technical Committee ISO/TC 34 "Agricultural
food products" in collaboration with Technical Committee CEN/TC 327 “Animal feeding stuffs - Methods of
sampling and analysis” the secretariat of which is held by NEN.
This document is currently submitted to the parallel Enquiry.
Endorsement notice
The text of ISO/DIS 6498:2009 has been approved by CEN as a prEN ISO 6498:2009 without any
modification.

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oSIST prEN ISO 6498:2009
DRAFT INTERNATIONAL STANDARD ISO/DIS 6498
ISO/TC 34/SC 10 Secretariat: NEN
Voting begins on: Voting terminates on:
2009-04-09 2009-09-09
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
Animal feeding stuffs — Guidelines for sample preparation
Aliments des animaux — Lignes directrices pour la préparation d'échantillons
[Revision of second edition (ISO 6498:1998)]
ICS 65.120

ISO/CEN PARALLEL PROCESSING
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REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
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RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT, WITH THEIR COMMENTS, NOTIFICATION OF ANY RELEVANT PATENT RIGHTS OF WHICH
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©
International Organization for Standardization, 2009

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Contents Page
Foreword .iv
1 Scope.1
2 Introduction.1
3 Definitions .1
4 Considerations to sample preparation errors .7
5 Principle.14
6 Safety precautions .15
7 Equipment .16
8 Procedure.17
9 Performance tests (quality control).28
10 Annexes: Categories of feeds – special remarks and flow charts.31
Bibliography.50

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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 6498 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 10, and by
Technical Committee CEN/TC 327, Animal feeding stuffs in collaboration.
This second/third/. edition cancels and replaces the first/second/. edition (), [clause(s) / subclause(s) /
table(s) / figure(s) / annex(es)] of which [has / have] been technically revised.

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Animal feeding stuffs — Guidelines for sample preparation
1 Scope
This European Standard specifies guidelines for the preparation of test samples from laboratory samples of
animal feeding stuffs including pet foods mostly quoted from AAFCO guidelines [1]. The guidelines are
overruled by special instructions for sample preparation demanded by specific analysis methods for feeding
stuffs (e.g. ISO, CEN, IEC).
2 Introduction
The sample preparation standard describes the procedure for preparing a sample coming to a laboratory (in
general with minimum weight of 0,5 kg) to get a homogeneous test sample (with minimum weight of 100 g)
with the same constitution, with the same composition and without any contamination.
From a test portion (of 0,2 g up to 25 g and more) for weighing to feedstuff analysis representative results
should be achieved of the laboratory sample and finally of the whole lot from which the sample was drawn.
Therefore all the steps for sample preparation should be done rather quickly, under convenient and very clean
conditions so there could be no degradation of sensitive substances, no contaminations and no oxidation
process due to influences of too high temperatures, daylight or air or from residues of apparatus used or from
samples prepared before or simultaneously.
A loss or a change of moisture during sample preparation must be taken into account for reporting results to
origin moisture content for feedstuff control (or to dry mass of 100% or 88%).
3 Definitions
3.1 Definitions concerning 'Sample'
3.1.1
lot
a quantity of material that is assumed to be a single population for sampling purposes
3.1.2
laboratory sample
that portion of material sent to or received by the laboratory
3.1.3
test sample
prepared after subsampling or splitting from the laboratory sample, from which test portions are removed for
testing or for analysis. It may be the laboratory sample if no preparation is required
3.1.4
test portion
the quantity of material, of proper mass and volume for measurement of the analyte or other property of
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interest, removed from the test sample, taken from the laboratory sample directly if no preparation of the
laboratory sample is required (e.g. with liquids), but usually taken from the prepared test sample
3.1.5
reserve sample
in general left material from the laboratory sample where splitted / subsampled test samples are taken away
from and where no further particle size reduction is done. If mycotoxin- or GMO-analysis are done from the
whole laboratory sample, then the reserve sample is reduced to the corresponding particle sizes too. The
reserve sample should be stored under conditions maintaining integrity
3.2 Definitions concerning 'Substances'
3.2.1
substance
analytes or constituents for which the feeding stuff is to be analysed. Substituents could be classified to/as
nutrients (e.g. crude protein), feed additives (e.g. vitamins), undesirable substances (e.g. heavy metals) and
banned substances (e.g. proteins from animal origin). Substances are analysed by microscopic, (micro-)
biological- or chemical procedures
3.2.1.1
stable substances
analytes or constituents which are not influenced by handling in the relevant sample preparation steps and by
storing at room temperature over a longer time period
3.2.1.2
not-stable substances
analytes or constituents which are (1) volatile, degradable, heat-sensitive or (2) sensitive to light, enzymatic
degradation or chemical oxidation, such that they are largely affected by sample preparation steps (e.g. partial
drying, freeze drying, grinding) or sample storage. The whole sample preparation should be done quickly and
carefully under adequate conditions. Especially the heating of mills during a long grinding procedure should
be avoided. The corresponding (test) samples should be treated and stored under low temperatures
(refrigerator and/or freezer) and protected from intensive air- and daylight-influences e.g. by using brown
glass vessels

Table 1 — Classification of analytes to stable or not stable substances and reasons for degradation

Reason(s) for

Not-stable substances:
Stable substances:
degradation / change:
(Crude) protein, fat,
Moisture Temperature (volatile)
Nutrients:
ash, fibre
Starch, sugar,
 Ammonia Temperature (volatile)
lactose
gas production, Organic acids (e.g. lactic acid, acetic acid,
enzyme soluble butyric acid, citric acid, fumaric acid, formic Temperature (volatile)
organic substance acid)
Minerals (e.g. Ca, P, Air oxidation (of double
 Fatty acids
Mg, Na, K, Cl) bonds)
Trace elements (e.g.
Feed Temperature, UV-light
Cu, Zn, Mn, Fe, Se, Vitamins (e.g. vitamin A, D , E)
3
additives: (sensitive)
Co)
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Amino acids (e.g.
lysine, methionine, 1,2-propandiol, glycol Temperature (volatile)
tryptophan)
Enzymes (e.g.
phytases, not starch Probiotics (e.g. Saccharomyces cerevisiae, Temperature (freezing),

polymerase Enterococcus faecium) pressure (sensitive)
enyzmes)
Mold growth and
Mycotoxins (e.g. aflatoxin B ,
1
change of mycotoxins
Undesirable Heavy metals (e.g. deoxynivalenol, fumonisins, ochratoxin A,
possible at room
substances: As, Pb, Cd, Hg) T-2 and HT-2 toxin, zearalenone, ergot
temperature; UV-light
alkaloids)
(sensitive –aflatoxin B )
1
Dioxins and PCB- Pesticides (e.g. PCBs, OCDs, other
 Temperature (sensitive)
like Dioxins pesticides)
  Hydrocyanic acid Temperature (volatile)
Banned Proteins of animal
Antibiotics Temperature (sensitive)
substances: origin

NOTE Too many microorganisms present in feeds can break down the organic compounds.
3.3 Definitions concerning `Animal feeding stuffs´
For identification and grouping a laboratory sample to the terms and annexes used within these guidelines
some specific definitions are given in this document.
NOTE Definitions of animal feeding stuffs are given by legislation worldwide. As an example definitions of European
directives and for straight feeds in an alphabetical list from a German committee are mentioned within the bibliography [8],
[9], [10], [11], [12], [13].
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3.3.1
birdseed
grains and oilseeds that are fed to birds
3.3.2
whole cottonseed
the entire unprocessed cottonseed product, including the hulls, lint, and meat of the cottonseed
3.3.3
mineral mix
consist mainly of mineral ingredient in either granular, bead, or small pelleted form. Vitamins, in encapsulated
or beadlet form, may be incorporated into the mix. The entire mix is free flowing
3.3.3.1
mineral pellets
agglomerated feed formed by compacting and forcing through die openings by a mechanical process
3.3.4
dry feeds
a feed ingredient or a complete animal feed which typically contain not more than 15% moisture, 15% fat, or
15% sugar
3.3.4.1
pellets
agglomerated feed formed by compacting and forcing through die openings by a mechanical process
3.3.5
forages inclusively silage, hay, haylage, total mixed ration and by-products
3.3.5.1
forage
edible parts of plants, other than separated grain, that can provide feed for grazing animals or that can be
harvested for feeding, including browse, herbage, and mast. Usage: Generally, the term refers to more
digestible material (i.e. what is called pasturage, hay, silage, dehydrated and green chop) in contrast to less-
digestible plant material, known as roughage
3.3.5.2
silage
forage preserved in a succulent condition by organic acids produced by partial anaerobic fermentation of
sugars in the forage
3.3.5.3
roughage
fibrous, coarsely textured parts of plants, such as stovers, straws, hulls, cobs, and stalks
3.3.5.4
hay
the aerial portion of grass or herbage especially cut and cured for animal feeding
3.3.5.5
haylage
product resulting from ensiling forage with about 45% moisture in the absence of oxygen

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3.3.5.6
total mixed ration (TMR)
a single mixture of all feed ingredients (forages, grains, and supplements) that is supplied to an animal for a
24-hour period. In practice, the 24-hour allotment of the mixture may be offered in one or more feedings.
3.3.5.7
by-products
products which remaining during process-procedures (e.g. from fermentation like dried destillers grains with
solubles = DDGS) for the production of ingredients from plant material
3.3.6
oilseed
any seed from which oil is expressed (i.e. sunflower seeds)
3.3.7
large block feed and molasses block feeds
agglomerated feed compressed into a solid mass cohesive enough to hold its form and weighing over one kg,
generally weighing about 20 kg. It may be marketed as a mineral block or a `caramelized´ molasses drum,
containing various minerals and nutrients. Samples may be received in the lab as large chunks, cores or
`sticky clumps´
3.3.8
liquid feed
a feed product that contains sufficient moisture to flow readily. A liquid feed is generally, if not always, a
molasses based product
3.3.9
canned pet foods
a pet food which has been processed, packaged, sealed, and sterilized for preservation in cans or similar
containers
3.3.10
semi-moist pet food
a meat based pet food that has been partially dried to prevent microbial decomposition. The moisture content
may range from 15% – 40%. The product generally is in the form of strips or cubes and is designed to be
stored at room temperature
3.3.10.1
dog chews
also known as `rawhide bones´. Meat strips that have been completely dried to a leather-like consistency
3.3.11
premixtures
a uniform mixture of one or more micro-ingredients with diluent and/or carrier. Premixes are used to facilitate
uniform dispersion of the micro-ingredients (i.e. drugs, antibiotics, and/or vitamins) in a large mix
3.3.12
range cube and alfalfa hay cubes
an agglomerated feed formed by compacting and forcing the mix through die openings by a mechanical
process. This results in a pellet that is about 2 cm diameter and 5 cm long. They may contain molasses to
help hold them together. Usually they are fed on the ground. This procedure also applies alfalfa cubes that
3
consists of chopped alfalfa hay oppressed into cubes usually larger than 16 cm
3.3.13
texturized and sticky feed
a mix of assorted grains and commercial feed (generally pelleted) all of which has been treated with a coating
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of molasses. Some of the grains may have been steam heated and / or rolled prior to incorporating into the
texturized feed
3.3.14
aquatic feed
aquatic feed which has been mechanically processed in forms of pellets, flakes, crumble, encapsulated and
as powder, packaged sealed and that are fed to aquatic animals
3.4 Definitions concerning 'Sample preparation procedure'
3.4.1
homogeneity
the degree to which a property or a constituent is uniformly distributed throughout a quantity of material.
Homogeneity may be considered to have been achieved in a practical sense when the sampling error of the
processed portion is negligible compared to the total error of the measurement system. Since homogeneity
depends on the size of the units under consideration, a mixture of two materials may be inhomogeneous at
the molecular or atomic level, but homogenous at the particulate level. However, uniform visual appearance
does not ensure compositional homogeneity
3.4.2
partial drying ('pre-drying')
part of the sample preparation procedure for feedstuff samples with a high moisture content (dry mass < 85%,
e.g. silages) in which the sample is carefully dried to allow subsequent sample preparation procedures to be
applied e.g. particle size reduction by grinding with a mill. The partial drying procedure depends on the
feeding stuff (e.g. at temperatures below 55°C to 60°C for silages), and on the heat stability of the substance
(e.g. 70°C ± 10°C for trace elements and heavy metals)
3.4.3
freeze drying ('pre-drying')
careful drying process in the vacuum under heat supply, in order to sublimate the moisture
3.4.4
coarser grinding ('pre-grinding')
in cases when the laboratory sample contains large lumps or its particle size is over 6 mm a firstly coarse
grinding step of the whole sample is done before mass reduction. Finally it is a kind of particle size reduction
to ensure homogeneity of the laboratory sample
3.4.5
mass reduction
part of the sample preparation procedure to reduce the mass of a laboratory sample by splitting or
subsampling it by the use of (stationary or rotary) dividers or by fractional (alternate) shovelling
3.4.6
particle size reduction
part of the sample preparation procedure done by chopping, crushing, cutting, blending (homogenizing),
macerating, milling (grinding), pressing, pulverizing to obtain a homogenous test sample for further analysis.
In general the particle size reduction follows the mass reduction step of the sample preparation procedure
with different sieve-size-options to ensure integrity of the test sample(s)
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Figure 1 —Illustration of definitions concerning 'Sample', 'Substances', and 'Sample preparation
procedure'

"SAMPLING"       Choice from Lot

"SAMPLE PREPARATION" Laboratory sample(s) (500 g) with:
Dry matter < 85%  Dry matter ≥ 85% Lumps or particles > 6 mm


Partial or freeze drying ( `pre-drying´ )   Coarser grinding ( `pre-grinding´ )



Mass reduction (subsampling / splitting)    Reserve sample

   Test sample(s) (100 g) for:
Particle size reduction    - Microscopy
with different sieve-size options    - Analysis of stable substances
(1,0 mm, 0,5 mm, < 0,5 mm, no grinding)  - Analysis of not-stable substances

"ANALYSIS"   Test portion(s) (0,2 to 25 g)
4 Considerations to sample preparation errors
Sample preparation steps have been shown to be some of the largest error of laboratory error. This error,
which is generally overlooked, may be much larger than the error in subsequent analytical procedures.
4.1 Subsampling and other errors
Sample heterogeneity may add to the total subsampling error (TSE) on two levels [4]:
4.1.1 Constitution heterogeneity
On a first level this is a result when not all of the particles of the laboratory sample have the same composition
(shape, size, density, etc). If a great overall composition-wise difference between the individual fragments
exists, the constitution heterogeneity is large, but if the fragments are more homogeneous constitution
heterogeneity is lower. The total contribution to heterogeneity is never zero, however, as that would be the
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case of all fragments being strictly identical. Mixing and blending does not change constitution heterogeneity.
The only way to alter the constitution heterogeneity of any given material would be by comminution (crushing /
cutting) or by other methods changing the physical properties of a sample. The reduction of the average grain-
size is the dominating factor in reducing constitution heterogeneity by such means.
Therefore a firstly coarse grinding (`pre-grinding´) of the whole laboratory sample before subsampling /
splitting reduces constitution heterogeneity.
This fundamental subsampling error (FSE) can be controlled by the appropriate choice of the test sample
mass (see 4.2). Therefore collect enough mass to ensure that all of the particles of different composition are
contained in the subsample / split. The larger the particle size of a material, the larger the mass of the
subsample must be to minimize error.
4.1.2 Distributional heterogeneity
On a second level this is the non-random distribution of particles in the sample, results mainly from the forces
of gravity to particles of different densities, sizes and shapes which leads to a grouping and segregation of all
particles. Particles with large differences in size and / or density tend to segregate or stratify heavily, with the
smallest and / or densest particles at the bottom of the sample. For the sake of illustration, imagine a
laboratory sample consisting of black and white spheres and with significantly different grain-size distributions:
If all the black spheres are to be found at the bottom of the sample and the white spheres are more to the top,
the system displays a very high distributional heterogeneity. If on the other hand the spheres were to be well
mixed (homogenized), the system distributional heterogeneity would be significantly reduced.
To reduce this grouping and segregation error (GSE) mix / blend the sample before subsampling and collect
many increments at random from the laboratory sample (see 4.3).
Mixing is not adequate for many materials: for some materials and circumstances mixing may actually
increase segregation instead of reducing the grouping and segregation error. As long as gravity exists there
will be segregation. Many materials will always display an innate propensity for segregation, even immediately
after mixing, e.g. highly density-fractionated materials, suspensions. Such systems require constant
monitoring and treatment, but once this feature has been duly recognized it can always be dealt with
satisfactory.
Increme
...

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