1、BRITISH STANDARD BS ISO 4121:2003 Sensory analysis Guidelines for the use of quantitative response scales ICS 67.240 BS ISO 4121:2003 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 26 November 2003 BSI 26 November 2003 ISBN 0 580 42970 9 Nat
2、ional foreword This British Standard reproduces verbatim ISO 4121:2003 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committee AW/12, Sensory analysis, which has the responsibility to: A list of organizations represented on this com
3、mittee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” fac
4、ility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligatio
5、ns. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pa
6、ges This document comprises a front cover, an inside front cover, the ISO title page, pages ii to iv, pages 1 to 9 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments Reference n
7、umber ISO 4121:2003(E) OSI 3002INTERNATIONAL STANDARD ISO 4121 Second edition 2003-11-15 Sensory analysis Guidelines for the use of quantitative response scales Analyse sensorielle Lignes directrices pour lutilisation dchelles de rponses quantitatives BSISO4121:2003IS:1214 O3002(E) DPlcsid Fremia ih
8、Ts PDF file mya ctnoian emdebt dedyfepcaes. In ccacnadrow eitA hebods licnesilop gnic,y tihs file mirp eb yatnde iv roweb detu slahl ton ide ebtlnu deess teh typfecaes wihce era hml era deddebicsnede ti dna onstlalde t noeh comuptfrep reromign tide ehtin.g In wodlnidaot gnihs fil,e trapise atpecc ti
9、ereht nser ehnopsiiblity fo nto ifnriigngn Aebods licnesilop gnic.y ehT ISO tneClar Secrteirata caceptl on siibality in this .aera Ai ebods a tedarmfo kra Aebod SystemI snctaropro.de teDials fo teh sfotwcudorp erats sut deo crtaee tihs PDF file cna f ebi dnuon tlareneG eh Ifnler oatit evt oeh file;
10、tP ehDc-Frtaeino marapteres wtpo ereimizf deirp rotni.gn Evc yresah era t neebakt nesne ot erutah teh fili es siutlbaf eosu rI yb eSO memdob rebeis. In tlnu ehikletneve y ttah lborp aem lertait gno it is f,dnuo plsaee ifnrom ttneC ehlar Secterirata ta teh serddaig sleb nevwo. ISO 3002 Athgir lls ser
11、evr.de selnUs towrehise specfidei, trap on fo thsi ilbupctanoi may cudorper ebtu ro dezilina ni dey fomr yb ro nam y,snae lecetrinoc m roceinahcla, icnliduntohp gcoiypom dna gnicrfoilm, wittuoh mrepissii non writif gnrmo ietI rehSta O tserdda ehs ebolw or ISOs memreb i ydobn the cnuotfo yr ttseuqer
12、ehe.r ISO cirypothg fofice saCe tsopale 65 eneG 1121-HC 02 av leT. 4 + 10 947 22 1 11 xaF0 947 22 14 + 9 74 E-mial coirypthgis.o gro We bwww.is.o groii ISO 3002 Allr ihgtsser edevrBSISO4121:2003IS:1214 O3002(E) I SO 3002 All irhgts seredevr iiiContents Page Foreword iv 1 Scope 1 2 Normative referenc
13、es. 1 3 Terms and definitions. 1 4 General considerations 3 5 Response scales. 3 5.1 General. 3 5.2 Numerical and verbal response scales. 3 5.3 Dynamic response scales 4 5.4 Pictorial response scales. 4 6 Choice of response scale. 5 6.1 General. 5 6.2 Choice of unipolar or bipolar response scale 5 6
14、.3 Choice of continuous or discrete response scale.5 6.4 Equality of the response scale intervals 6 6.5 Quality of the measurements obtained using response scales. 6 6.6 Statistical analysis 6 Annex A (informative) Application examples 7 Bibliography . 9 BSISO4121:2003IS:1214 O3002(E) iv I SO 3002 A
15、ll irhgts seredevrForeword 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 sub
16、ject 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 (I
17、EC) 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 commit
18、tees 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
19、 held responsible for identifying any or all such patent rights. ISO 4121 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 4121:1987), which has been technically revised. BSISO4121:2003
20、INTENRATIONAL TSANDADR IS:1214 O3002(E)I SO 3002 All irhgts seredevr 1Sensory analysis Guidelines for the use of quantitative response scales 1 Scope This International Standard provides guidelines describing quantitative response scales (where the response obtained indicates the intensity of percep
21、tion) and their use when assessing samples. It is applicable to all quantitative assessment, whether global or specific and whether objective or hedonic. It is intentionally limited to the most commonly used measurement scales for sensory assessment. It is necessary to distinguish between two common
22、 uses of the term “scale”: response scale (see 3.1), and measurement scale (see 3.5). NOTE Annex A gives examples of an application. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies.
23、 For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 5492, Sensory analysis Vocabulary ISO 6658, Sensory analysis Methodology General guidance ISO 8586-1, Sensory analysis General guidance for the selection, training and monitoring of assesso
24、rs Part 1: Selected assessors ISO 8586-2, Sensory analysis General guidance for the selection, training and monitoring of assessors Part 2: Experts ISO 8587, Sensory analysis Methodology Ranking 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 5492 an
25、d the following apply. 3.1 response scale means (e.g. numerical, verbal or pictorial) by which an assessor registers a quantitative response NOTE 1 In sensory analysis, this is a device or tool to capture the reaction of an assessor to some property such that it can be converted into numbers. NOTE 2
26、 The term “scale” is widely used as being equivalent to the expression “response scale”. BSISO4121:2003IS:1214 O3002(E) 2 I SO 3002 All irhgts seredevr3.2 measure, verb record the quantity of a property 3.3 measurement action of measuring 3.4 measurement number resulting from the action of measuring
27、 3.5 measurement scale formal relationship (e.g. ordinal, interval or ratio) between a property (e.g. the intensity of a sensory perception) and the numbers used to represent values of the property (e.g. numbers registered by the assessors or derived from the assessors responses) NOTE The term “scal
28、e” is widely used as being equivalent to the expression “measurement scale”. 3.5.1 ordinal scale scale in which the order of the values allocated corresponds to the order of the intensities perceived for the property being assessed NOTE The size of the difference between two values cannot be assumed
29、 to reflect the difference between the perceived intensities. Neither can the ratio of two values be assumed to reflect the ratio of the perceived intensities. EXAMPLES Richter scale of earthquake intensity and Beaufort scale of wind strength. 3.5.2 interval scale scale which, in addition to possess
30、ing the attributes of an ordinal scale, is distinguished by the fact that equal differences between numerical values correspond to equal differences between properties measured (in sensory analysis, perceived intensities) NOTE Larger values correspond to larger perceived intensities and the size of
31、the difference between two values reflects the size of the difference in perceived intensity of the property being measured. However, a numerical value of zero may not indicate a total absence of the property and the ratio of two values cannot be assumed to reflect the ratio of the perceived intensi
32、ties. EXAMPLES Celsius and Fahrenheit temperature scales. 3.5.3 ratio scale scale which has the properties of an interval scale but for which, in addition, the ratio between the values allocated to two stimuli is equal to the ratio between the perceived intensities of these stimuli NOTE 1 With this
33、scale, a numerical value of zero designates total absence of the property. NOTE 2 The ratio scale is the only case for which it is meaningful to say that one result is, for instance, ten times as great as another. EXAMPLES Kelvin temperature scale, mass and length scales. BSISO4121:2003IS:1214 O3002
34、(E) I SO 3002 All irhgts seredevr 33.6 referencing use of one or more specified standards to designate particular values (numeric or semantic) on the response scale NOTE 1 A specified concentration of sucrose in water may correspond to a specified numerical value on a scale of sweetness. NOTE 2 A re
35、ference is not always physical (e.g. a hedonic ideal). 3.7 end effect tendency of assessors to under-use or over-use the extremities of the response scale NOTE The most usual end effect is for assessors to avoid using the highest and lowest scale values, one reason being to leave responses available
36、 for future, extreme samples that do not, in fact, occur. 4 General considerations All methodologies that use response scales should take the following into account: the usual general conditions under which sensory analyses should be carried out; refer in particular to the International Standards co
37、ncerning general guidance for sensory analysis (ISO 6658), layout of test rooms intended for sensory analysis (ISO 8589), selection and training of assessors and experts (ISO 8586-1 and ISO 8586-2); specific standards that use the relevant scale, for example, sensory profiles (ISO 6564, ISO 13299) o
38、r classification (ISO 8587). 5 Response scales 5.1 General A distinction can be made between numerical, verbal, dynamic and pictorial scales. However, all types of response scale are usually translated into numbers for the purposes of analysis and interpretation (see Figure 1). 5.2 Numerical and ver
39、bal response scales Numerical and verbal response scales are the types most commonly used in sensory analysis. Some examples are shown in Figure 1. For more details, see 4 and 5. Each assessor gives a response either by selecting it on a questionnaire (e.g. by circling the appropriate response or by
40、 marking the appropriate box) or by producing it (e.g. by writing down a number to represent the perceived intensity or by marking a position on a line). Line scales permit unlimited fineness of differentiation among responses and are examples of continuous scales, whereas category scales allow only
41、 certain predefined responses and are examples of discrete scales (see 6.3). BSISO4121:2003IS:1214 O3002(E) 4 I SO 3002 All irhgts seredevrFigure 1 Examples of response scales 5.3 Dynamic response scales Dynamic response scales are continuous scales used, for example, to record the intensity of a pe
42、rception as it changes over time. The assessor may move a cursor along an intensity scale using a computer mouse or joystick, or may adjust a potentiometer, or the spacing of his or her fingers. 5.4 Pictorial response scales Pictorial response scales are discrete scales. They are often presented in
43、the form of a series of stylized faces that illustrate different expressions from extreme liking to extreme dislike. They are often used for hedonic tests conducted with children whose reading and/or understanding capacities are limited. The assessor indicates the face to the person conducting the e
44、xperiment or selects it himself/herself. The various expressions are then converted into numbers in order to be processed (see 6). BSISO4121:2003IS:1214 O3002(E) I SO 3002 All irhgts seredevr 56 Choice of response scale 6.1 General The choice of response scale depends on the objectives of the study,
45、 the products being studied and the panel. Whatever response scale is adopted, it is necessary that it be easily understood by the assessors, easy to use, discriminating, and unbiased. 6.2 Choice of unipolar or bipolar response scale The polarity of a scale is defined by the location of the neutral
46、or zero point: in a unipolar scale, the neutral or zero point is located at one end of the scale; in a bipolar scale, the neutral or zero point is located at the centre of the scale. A bipolar scale is used when the intensity of a property can differ in either direction from a neutral or ideal value
47、. For example, a bipolar scale may run from “Not sweet enough” to “Too sweet”, whereas a unipolar scale may run from “Not at all sweet” to “Extremely sweet”. When constructing bipolar scales, an inappropriate choice of scale anchors can produce a scale that does not form a true continuum and has no
48、logical centre point. Avoid the use of anchors that are not based on a single attribute (e.g. “dark brown” to “bright red”) unless they lie on a recognized sequence of stages or grades of the product. 6.3 Choice of continuous or discrete response scale 6.3.1 Continuous scale Assessors may be asked t
49、o make numerical responses on a continuous scale, meaning that numbers with fractional parts can be used. Line scales are typically 15 cm (6 in) long, labelled at each end with the extreme values of the attribute being assessed. The assessor responds by marking the line in the position corresponding to the perceived intensity. The marked position is converted to a number by the analyst. A continuous scale gives
