SIST EN ISO 6498:2012

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.

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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

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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
This draft has been developed within the European Committee for Standardization (CEN), and processed
under the CEN-lead mode of collaboration as defined in the Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member bodies for a parallel
five-month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments received, will be
submitted to a parallel two-month approval vote in ISO and formal vote in CEN.
In accordance with the provisions of Council Resolution 15/1993 this document is circulated in
the English language only.
Conformément aux dispositions de la Résolution du Conseil 15/1993, ce document est distribué
en version anglaise seulement.
To expedite distribution, this document is circulated as received from the committee secretariat.
ISO Central Secretariat work of editing and text composition will be undertaken at publication
stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.
THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
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.
©
International Organization for Standardization, 2009

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©
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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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oSIST prEN ISO 6498:2009
DRAFT INTERNATIONAL STANDARD ISO/DIS 6498

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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