EN ISO 16624:2020

SLOVENSKI STANDARD
01-maj-2020
Pšenična moka in pšenični zdrob durum - Določanje barve z difuzno refleksno
kolorimetrijo (ISO 16624:2020)
Wheat flour and durum wheat semolina - Determination of colour by diffuse reflectance
colorimetry (ISO 16624:2020)
Weichweizenmehl und Hartweizengrieß - Farbbestimmung mittels diffuser
Reflexionskolorimetrie (ISO 16624:2020)
Farine de blé tendre et semoule de blé dur - Détermination de la couleur par colorimétrie
par réflectance diffuse (ISO 16624:2020)
Ta slovenski standard je istoveten z: EN ISO 16624:2020
ICS:
67.060 Žita, stročnice in proizvodi iz Cereals, pulses and derived
njih products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 16624
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2020
EUROPÄISCHE NORM
ICS 67.060
English Version
Wheat flour and durum wheat semolina - Determination
of colour by diffuse reflectance colorimetry (ISO
16624:2020)
Farine de blé tendre et semoule de blé dur - Weichweizenmehl und Hartweizengrieß -
Détermination de la couleur par colorimétrie par Farbbestimmung mittels diffuser
réflectance diffuse (ISO 16624:2020) Reflexionskolorimetrie (ISO 16624:2020)
This European Standard was approved by CEN on 15 March 2020.

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, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 16624:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 16624:2020) has been prepared by Technical Committee ISO/TC 34 "Food
products" in collaboration with Technical Committee CEN/TC 338 “Cereal and cereal products” the
secretariat of which is held by AFNOR.
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 September 2020, and conflicting national standards
shall be withdrawn at the latest by September 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
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,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 16624:2020 has been approved by CEN as EN ISO 16624:2020 without any modification.

INTERNATIONAL ISO
STANDARD 16624
First edition
2020-03
Wheat flour and durum wheat
semolina — Determination of colour
by diffuse reflectance colorimetry
Farine de blé tendre et semoule de blé dur — Détermination de la
couleur par colorimétrie de réflectance diffuse
Reference number
ISO 16624:2020(E)
©
ISO 2020
ISO 16624:2020(E)
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

ISO 16624:2020(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus . 2
6 Sample preparation . 2
7 Procedure. 2
7.1 General . 2
7.2 Setting of the colorimeter . 3
7.3 Colorimetric determination . 3
8 Expression of the results . 3
9 Precision . 3
9.1 General . 3
9.2 Repeatability limit, r .3
9.3 Reproducibility limit, R .3
9.4 Critical difference, d . 4
C
9.4.1 General. 4
9.4.2 Comparison of two groups of measurements in one laboratory . 4
9.4.3 Comparison of two groups of measurements in two laboratories . 4
9.5 Uncertainty, U .4
10 Test report . 5
Annex A (informative) Results of the interlaboratory test . 6
Bibliography .12
ISO 16624:2020(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.
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 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 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 www .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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 4,
Cereals and pulses, in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 338, Cereal and cereal products, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved

INTERNATIONAL STANDARD ISO 16624:2020(E)
Wheat flour and durum wheat semolina — Determination
of colour by diffuse reflectance colorimetry
1 Scope
This document specifies a method for the determination of colour in durum wheat semolina and wheat
flour by diffuse reflectance colorimetry.
It is applicable to industrial semolina and flour.
The method can be applicable to flour obtained from experimental mill.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
colour metric space
expression of the colour of an object or of a light source by some parameters expressed by figures
3.2
illuminant
light source characterized by a spectral curve, where the energy relative distribution is defined in the
field of wavelengths that are able to influence the object colour vision
4 Principle
The principle is based on the measurement of colour directly on semolina and flour by a reflectance
colorimeter.
The colour of wheat milling product (semolina and flour) is due to the pigments
...