EN ISO 4120:2007
(Main)Sensory analysis - Methodology - Triangle test (ISO 4120:2004)
Sensory analysis - Methodology - Triangle test (ISO 4120:2004)
ISO 4120:2004 describes a procedure for determining whether a perceptible sensory difference or similarity exists between samples of two products. The method is a forced-choice procedure. The method applies whether a difference can exist in a single sensory attribute or in several attributes.
The method is statistically more efficient than the duo-trio test, but has limited use with products that exhibit strong carryover and/or lingering flavours.
The method is applicable even when the nature of the difference is unknown (i.e. it determines neither the size nor the direction of difference between samples, nor is there any indication of the attributes responsible for the difference). The method is applicable only if the products are fairly homogeneous.
The method is effective for a) determining that either a perceptible difference results (triangle testing for difference), or a perceptible difference does not result (triangle testing for similarity) when, for example, a change is made in ingredients, processing, packaging, handling or storage; b) or for selecting, training and monitoring assessors.
Sensorische Analyse - Prüfverfahren - Dreiecksprüfung (ISO 4120:2004)
Diese Internationale Norm beschreibt ein Verfahren zur Feststellung, ob zwischen den Proben von zwei Prüf¬materialien ein wahrnehmbarer sensorischer Unterschied oder Ähnlichkeit vorhanden ist. Bei dem Verfahren wird nach dem Forced-Choice-Prinzip vorgegangen. Das Verfahren ist anwendbar, wenn der Unterschied nur bei einem einzelnen sensorischen Merkmal oder auch bei mehreren Merkmalen vorliegen kann.
Das Verfahren ist statistisch aussagekräftiger als die Duo-Trio-Prüfung, hat aber eine begrenzte Anwendung bei Prüfmaterialien, die starke überdeckende und/oder nachwirkende olfaktorische/gustatorische Eindrücke hinterlassen.
Das Verfahren ist auch anwendbar, wenn die Art des Unterschiedes unbekannt ist [das heißt, es bestimmt weder Größe noch Richtung eines Unterschiedes zwischen den Proben, noch liefert es Hinweise auf Merk¬male, die für den Unterschied verantwortlich sind]. Das Verfahren ist nur anwendbar, wenn die Prüfmaterialien homogen sind.
Das Verfahren eignet sich besonders für:
a) die Untersuchung daraufhin
ob ein wahrnehmbarer Unterschied (Dreiecksprüfung auf Unterschied) resultiert, oder
ob kein wahrnehmbarer Unterschied (Dreiecksprüfung auf Ähnlichkeit) resultiert, wenn zum Beispiel eine Änderung von Zutaten, Verarbeitung, Verpackung, Behandlung oder Lagerung vorgenommen wurde.
b) Oder für die Auswahl, Schulung und Leistungsüberprüfung von Prüfpersonen.
Analyse sensorielle - Méthodologie - Essai triangulaire (ISO 4120:2004)
L'ISO 4120:2004 décrit un mode opératoire permettant de déterminer s'il existe une différence sensorielle perceptible ou une similitude entre les échantillons de deux produits. La méthode est une procédure à choix forcé. Elle s'applique s'il existe une différence pour une seule propriété sensorielle ou pour plusieurs.
La méthode est statistiquement plus efficace que l'essai duo-trio, mais est d'une utilisation limitée pour les produits présentant une forte rémanence et/ou des arômes persistants.
La méthode est applicable même lorsque la nature de la différence est inconnue, ce qui signifie qu'elle ne détermine ni la taille ni le sens de la différence entre des échantillons et qu'elle ne donne pas non plus d'indications sur la ou les propriétés à l'origine de cette différence. La présente méthode n'est applicable que si les produits sont relativement homogènes.
La méthode est efficace pour a) déterminer qu'il existe une différence perceptible (essai triangulaire de différence), ou qu'il n'existe pas de différence perceptible (essai triangulaire de similitude) quand, par exemple, des modifications sont apportées aux ingrédients, à la transformation, à l'emballage, aux opérations de manutention ou de stockage; b) ou pour sélectionner, entraîner et contrôler les sujets.
Senzorična analiza - Metodologija - Preskus "triangel" (ISO 4120:2004)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-november-2007
6HQ]RULþQDDQDOL]D0HWRGRORJLMD3UHVNXVWULDQJHO ,62
Sensory analysis - Methodology - Triangle test (ISO 4120:2004)
Sensorische Analyse - Prüfverfahren - Dreiecksprüfung (ISO 4120:2004)
Analyse sensorielle - Méthodologie - Essai triangulaire (ISO 4120:2004)
Ta slovenski standard je istoveten z: EN ISO 4120:2007
ICS:
67.240 6HQ]RULþQDDQDOL]D Sensory analysis
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
EN ISO 4120
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2007
ICS 67.240
English Version
Sensory analysis - Methodology - Triangle test (ISO 4120:2004)
Analyse sensorielle - Méthodologie - Essai triangulaire (ISO Sensorische Analyse - Prüfverfahren - Dreiecksprüfung
4120:2004) (ISO 4120:2004)
This European Standard was approved by CEN on 12 July 2007.
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 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 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.
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EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4120:2007: E
worldwide for CEN national Members.
Foreword
The text of ISO 4120:2004 has been prepared by Technical Committee ISO/TC 34 "Agricultural
food products” of the International Organization for Standardization (ISO) and has been taken
over as EN ISO 4120:2007 by Technical Committee CEN/SS C01 "Food Products", the
secretariat of which is held by CMC.
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 January 2008, and conflicting national
standards shall be withdrawn at the latest by January 2008.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: 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.
Endorsement notice
The text of ISO 4120:2004 has been approved by CEN as EN ISO 4120:2007 without any
modifications.
INTERNATIONAL ISO
STANDARD 4120
Second edition
2004-06-15
Sensory analysis — Methodology —
Triangle test
Analyse sensorielle — Méthodologie — Essai triangulaire
Reference number
ISO 4120:2004(E)
©
ISO 2004
ISO 4120:2004(E)
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ii © ISO 2004 – All rights reserved
ISO 4120:2004(E)
Contents Page
Foreword. iv
1 Scope. 1
2 Normative references . 1
3 Terms and definitions. 1
4 Principle . 2
5 General test conditions and requirements. 3
6 Assessors . 3
6.1 Qualification . 3
6.2 Number of assessors. 3
7 Procedure. 4
8 Analysis and interpretation of results . 4
8.1 When testing for a difference . 4
8.2 When testing for similarity. 5
9 Test report. 5
10 Precision and bias . 5
Annex A (normative) Tables. 6
Annex B (informative) Examples. 10
Bibliography . 15
ISO 4120:2004(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 4120 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 12, Sensory
analysis.
This second edition cancels and replaces the first edition (ISO 4120:1983), which has been technically revised.
iv © ISO 2004 – All rights reserved
INTERNATIONAL STANDARD ISO 4120:2004(E)
Sensory analysis — Methodology — Triangle test
1 Scope
This International Standard describes a procedure for determining whether a perceptible sensory difference or
similarity exists between samples of two products. The method is a forced-choice procedure. The method is
applicable whether a difference exists in a single sensory attribute or in several attributes.
The method is statistically more efficient than the duo-trio test (described in ISO 10399), but has limited use
with products that exhibit strong carryover and/or lingering flavours.
The method is applicable even when the nature of the difference is unknown [i.e. it determines neither the size
nor the direction of difference between samples, nor is there any indication of the attribute(s) responsible for
the difference]. The method is applicable only if the products are fairly homogeneous.
The method is effective for
a) determining that
either a perceptible difference results (triangle testing for difference), or
a perceptible difference does not result (triangle testing for similarity) when, for example, a change is
made in ingredients, processing, packaging, handling or storage;
b) or for selecting, training and monitoring assessors.
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.
ISO 5492:1992, Sensory analysis — Vocabulary
ISO 8589:1988, Sensory analysis — General guidance for the design of test rooms
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5492 and the following apply.
3.1
alpha-risk
αα-risk
αα
probability of concluding that a perceptible difference exists when one does not
NOTE This is also known as Type I error, significance level or false positive rate.
ISO 4120:2004(E)
3.2
beta-risk
ββββ-risk
probability of concluding that no perceptible difference exists when one does
NOTE This is also known as Type II error or false negative rate.
3.3
difference
situation in which samples can be distinguished based on their sensory properties
NOTE The proportion of assessments in which a perceptible difference is detected between the two products is given
the symbol p .
d
3.4
product
material to be evaluated
3.5
sample
unit of product prepared, presented and evaluated in the test
3.6
sensitivity
general term used to summarize the performance characteristics of the test
NOTE In statistical terms, the sensitivity of the test is defined by the values of α, β and p .
d
3.7
similarity
situation in which any perceptible differences between the samples are so small that the products can be used
interchangeably
3.8
triad
those three samples given to an assessor in the triangle test
NOTE In the triangle test, each sample is marked with a different code. Two of the samples are alike (i.e. from one
product) and one is different (i.e. from the other product).
4 Principle
The number of assessors is chosen based on the sensitivity desired for the test. (See 6.2 and the discussion
in A.3.)
Assessors receive a set of three samples (i.e. a triad) and are informed that two of the samples are alike and
that one is different. The assessors report which sample they believe to be different, even if the selection is
based only on a guess.
The number of correct responses is counted and the significance is determined by reference to a statistical
table.
2 © ISO 2004 – All rights reserved
ISO 4120:2004(E)
5 General test conditions and requirements
5.1 Clearly define the test objective in writing.
5.2 Carry out the test under conditions that prevent communication among assessors until all the
evaluations have been completed, using facilities and booths that comply with ISO 8589.
5.3 Prepare the samples out of sight of the assessors and in an identical manner (i.e. same apparatus,
same vessels, same quantities of product).
5.4 Assessors shall not be able to identify the samples from the way in which they are presented. For
example, in a taste test, avoid any differences in appearance. Mask any irrelevant colour differences using
light filters and/or subdued illumination.
5.5 Code the vessels containing the samples in a uniform manner, preferably using three-digit numbers,
chosen at random for each test. Each triad is composed of three samples, each with a different code.
Preferably, different codes should be used for each assessor during a session. However, the same three
codes may be used for all assessors within a test, provided that each code is used only once per assessor
during a test session (e.g. if several triangle tests on different products are being conduct
...
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