1、Sensory analysis Methodology “ A“ - “not A“ test BS ISO 8588:2017 BSI Standards Publication WB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06 ISO 2017 Sensory analysis Methodology “ A” “not A” test Analyse sensorielle Mthodologie Essai “A” “non A” INTERNATIONAL STANDARD ISO 8588 Second editio
2、n 2017-07 Reference number ISO 8588:2017(E) National foreword This British Standard is the UK implementation of ISO 8588:2017. It supersedes BS 59295:1988, which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee AW/12, Sensory analysis. A list of organization
3、s represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017 Published by BSI Standards Limited 2017 ISBN
4、 978 0 580 84456 0 ICS 67.240 Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2017. Amendments/corrigenda issued since publication Date Text affected BR
5、ITISH STANDARD BS ISO 8588:2017 ISO 2017 Sensory analysis Methodology “ A” “not A” test Analyse sensorielle Mthodologie Essai “A” “non A” INTERNATIONAL STANDARD ISO 8588 Second edition 2017-07 Reference number ISO 8588:2017(E) BS ISO 8588:2017 ISO 8588:2017(E)ii ISO 2017 All rights reserved COPYRIGH
6、T PROTECTED DOCUMENT ISO 2017, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, witho
7、ut prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.
8、org BS ISO 8588:2017 ISO 8588:2017(E)ii ISO 2017 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechani
9、cal, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Swi
10、tzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgISO 8588:2017(E)Foreword iv 1 Scope . 1 2 Normative references 1 3 T erms and definitions . 1 4 Principle 2 5 Apparatus . 2 6 Sampling 2 7 General test conditions 2 8 Assessors 3 8.1 Qualification, selection, arrangement
11、 . 3 8.2 Numbers of assessors and assessments . 3 9 Procedure. 3 10 Expression of results 4 Annex A (informative) Examples of the application of the “ A” “not A” test 6 Annex B (informative) Extr acts fr om 2and standard normal tables 10 Annex C (informative) Examples of answer forms for an “ A” “no
12、t A” test 11 Bibliography .13 ISO 2017 All rights reserved iii Contents Page BS ISO 8588:2017 ISO 8588:2017(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 i
13、s 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 par
14、t in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particu
15、lar the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives). Attention is drawn to the possibility that some of the elements of
16、this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see w
17、ww .iso .org/ patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well
18、as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html. This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 12, Sensory analysis. T
19、his second edition cancels and replaces the first edition (ISO 8588:1987), which has been technically revised. The following changes have been made: more detailed explanations of all aspects of the test method have been added; the option of testing more than one “not A” sample in a single test has b
20、een added; statistical calculations are presented in detail for all examples; an alternative data analysis procedure that deals directly with the one-sided nature of the “A” “not A” test has been added.iv ISO 2017 All rights reserved BS ISO 8588:2017 ISO 8588:2017(E) Foreword ISO (the International
21、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 esta
22、blished 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 standardiza
23、tion. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance wi
24、th the editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives). 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. Details of
25、any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endor
26、sement. For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
27、 URL: www .iso .org/ iso/ foreword .html. This document 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 8588:1987), which has been technically revised. The following changes have been
28、made: more detailed explanations of all aspects of the test method have been added; the option of testing more than one “not A” sample in a single test has been added; statistical calculations are presented in detail for all examples; an alternative data analysis procedure that deals directly with t
29、he one-sided nature of the “A” “not A” test has been added.iv ISO 2017 All rights reserved INTERNATIONAL ST ANDARD ISO 8588:2017(E) Sensory analysis Methodology “ A” “not A” test 1 Scope This document specifies a procedure for determining whether a perceptible sensory difference exists between sampl
30、es of two products. The method applies whether a difference exists in a single sensory attribute or in several. The “A” “not A” test can be used in sensory analysis in the following ways: a) as a difference test, particularly for evaluating samples having variations, for example, in appearance (maki
31、ng it difficult to obtain strictly identical repeat samples) or in aftertaste (making direct comparison difficult); b) as a recognition test, particularly for determining whether an assessor or group of assessors identifies a new stimulus in relation to a known stimulus (for example, recognition of
32、the quality of the sweet taste of a new sweetener); c) as a perception test, to determine the ability of an assessor to discriminate stimuli. The “A” “not A” test is not appropriate for assessing if two products are sufficiently similar to be used interchangeably (i.e. for similarity testing) becaus
33、e the “A” “not A” test inherently involves replicate evaluations of the same products by all assessors. These replicate evaluations violate the basic assumptions for similarity tests to be statistically valid. Examples of its application are given in Annex B. NOTE Bi and Ennis 1point out that the es
34、timate of the discriminal distance, d, between the “A” and “not A” samples is the same regardless of the nature of the replicated evaluations performed in the test but that the estimate of the variance of d does depend on how the replicate evaluations were performed. As such, no general discussion o
35、f a Thurstonian analysis of the “A” “not A” method, nor of the power of the test is undertaken in this document. Interested readers are referred to Reference 1 for a detailed discussion of the topic. 2 Normative references The following documents are referred to in the text in such a way that some o
36、r all of their content constitutes requirements 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 3534-1, Statistics Vocabulary and symbols Part 1: General statistical
37、terms and terms used in probability ISO 5492, Sensory analysis Vocabulary ISO 8586:2012, Sensory analysis General guidelines for the selection, training and monitoring of selected assessors and expert sensory assessors ISO 8589, Sensory analysis General guidance for the design of test rooms 3 T erms
38、 an d definiti ons For the purpose of this document, the terms and definitions given in ISO 5492, for terms concerning sensory analysis, and ISO 3534-1, for statistical terms, apply. ISO 2017 All rights reserved 1 BS ISO 8588:2017 ISO 8588:2017(E) ISO and IEC maintain terminological databases for us
39、e in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp 4 Principle An assessor is presented with a series of samples, some of which are composed of the “A” product whi
40、le others are composed of one or more “not A” products. For each sample, the assessor indicates whether the sample is an “A” product or is a “not A” product. This test requires the assessor to be familiar with product “A”, possibly through exposure to known samples of product “A”, prior to exposure
41、to the test samples. 5 Apparatus The apparatus shall be selected by the test supervisor according to the nature of the product to be analysed, the number of samples, etc. and shall in no way affect the test results. If standard apparatus corresponds to the needs of the test, it shall be used. 6 Samp
42、ling Refer to sampling standards for the sensory analysis of the product or products being tested. In the absence of such standards, agreement shall be sought among the parties concerned. 7 General test conditions 7.1 Clearly define the test objective in writing. 7.2 Carry out each session of the te
43、st under conditions that prevent communication among assessors until all evaluations have been completed. 7.3 The facilities in which the tests are conducted shall comply with ISO 8589. 7.4 Assessors shall not be able to identify the samples from the way in which they are presented. For example, in
44、a taste test, one should avoid any differences in temperature or appearance. Mask any irrelevant colour differences using, for example, light filters, subdued lighting or opaque serving vessels. 7.5 Code the vessels that contain the test samples in a uniform manner, using 3-digit numbers chosen at r
45、andom for each sample. Each test sample in a set shall have a different code. The same two codes (one for the “ A“ sample and one for the “not A“ sample) can be used for all assessors within a test session provided different codes are used from one session to another, if multiple sessions are requir
46、ed to complete the test. 7.6 The quantity or volume of product served shall be identical for all test samples. In a taste test, the quantity or volume to be placed in the mouth can be specified. If it is not, assessors shall be instructed to evaluate the same quantity or volume of each test sample.
47、7.7 The temperatures of the test samples shall be identical, preferably at the temperature at which the product is generally consumed.2 ISO 2017 All rights reserved BS ISO 8588:2017 ISO 8588:2017(E) ISO and IEC maintain terminological databases for use in standardization at the following addresses:
48、IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp 4 Principle An assessor is presented with a series of samples, some of which are composed of the “A” product while others are composed of one or more “not A” pro
49、ducts. For each sample, the assessor indicates whether the sample is an “A” product or is a “not A” product. This test requires the assessor to be familiar with product “A”, possibly through exposure to known samples of product “A”, prior to exposure to the test samples. 5 Apparatus The apparatus shall be selected by the test supervisor according to the nature of the product to be analysed, the number of samples, etc. and shall in no way affect the te
