EN ISO 6647-2:2020

Rice - Determination of amylose content - Part 2: Spectrophotometric routine method without defatting procedure and with calibration from rice standards (ISO 6647-2:2020)

This document specifies two simplified routine methods for the determination of the amylose mass fraction of milled rice, non-parboiled. The main difference between the two methods is the dispersion procedure: method A specifies hot dispersion, and method B specifies cold dispersion.
Both methods are applicable to rice with an amylose mass fraction higher than 5 %.
NOTE    These methods describe simplified procedures for the preparation of samples, which are frequently used in routine laboratories. The methods use the same reagents as the reference method (see ISO 6647-1), but omit the defatting step. Rice samples where the amylose mass fraction has been determined by the reference method are used as standards.

Reis - Bestimmung des Amylosegehalts - Teil 2: Spektrophotometrische Routineverfahren ohne Entfettungsverfahren und mit Kalibrierung nach Reisstandards (ISO 6647 2:2020)

Dieses Dokument legt zwei vereinfachte Routineverfahren zur Bestimmung des Amylose-Massenanteils von gemahlenem nicht-angekochten Reis fest. Der Hauptunterschied zwischen den beiden Verfahren besteht in der Vorgehensweise bei der Dispergierung: Verfahren A legt die Heiß-Dispergierung fest und Verfahren B legt die die Kalt-Dispergierung fest.
Beide Verfahren sind anwendbar auf Reis mit einem Amylose-Massenanteil von mehr als 5 %.
ANMERKUNG Diese Verfahren beschreiben vereinfachte Vorgehensweisen für die Herstellung von Proben, die in üblichen Laboratorien häufig genutzt werden. Die Verfahren nutzen als Referenzverfahren (siehe ISO 6647-1) dieselben Reagenzien, lassen jedoch den Schritt der Entfettung aus. Als Standards werden Reisproben genutzt, bei denen Amylose-Massenanteil mit dem Referenzverfahren bestimmt wurde.

Riz - Détermination de la teneur en amylose - Partie 2: Méthode spectrophotométrique de routine sans mode opératoire de dégraissage et avec étalonnage à l'aide d'étalons de riz (ISO 6647-2:2020)

Le présent document spécifie deux méthodes de routine simplifiées pour la détermination de la fraction massique d'amylose du riz usiné, non étuvé. La principale différence entre les deux méthodes est le mode opératoire de dispersion: la méthode A spécifie une dispersion à chaud et la méthode B spécifie une dispersion à froid.
Les deux méthodes sont applicables au riz avec une fraction massique d'amylose supérieure à 5 %.
NOTE    Ces méthodes décrivent des modes opératoires simplifiés pour la préparation d'échantillons, qui sont fréquemment utilisés en routine par les laboratoires. Les méthodes utilisent les mêmes réactifs que la méthode de référence (voir l'ISO 6647-1), mais omettent l'étape de dégraissage. Les échantillons de riz pour lesquels la fraction massique d'amylose a été déterminée par la méthode de référence sont utilisés comme étalons.

Riž - Določevanje amiloze - 2. del: Spektrofotometrijska rutinska metoda brez postopka razmaščevanja in s kalibracijo v skladu s standardi za riž (ISO 6647-2:2020)

General Information

• Status: Published
• Publication Date: 11-Aug-2020
• Withdrawal Date: 27-Feb-2021
• ICS: 67.060 - Cereals, pulses and derived products
• Technical Committee: CEN/TC 338 - Cereal and cereal products
• Drafting Committee: CEN/TC 338 - Cereal and cereal products
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 12-Aug-2020
• Completion Date: 12-Aug-2020
• Ref Project: SIST EN ISO 6647-2:2020 - Rice - Determination of amylose content - Part 2: Spectrophotometric routine method without defatting procedure and with calibration from rice standards (ISO 6647-2:2020)

Relations

• Replaces: EN ISO 6647-2:2015 - Rice - Determination of amylose content - Part 2: Routine methods (ISO 6647-2:2015)
• Effective Date: 19-Aug-2020

Overview

EN ISO 6647-2:2020 - "Rice - Determination of amylose content - Part 2" describes a spectrophotometric routine method without a defatting procedure, using calibration from rice standards. Published by CEN/ISO, this part specifies two simplified, routine procedures (hot dispersion - Method A, and cold dispersion - Method B) for determining the amylose mass fraction of milled, non‑parboiled rice. The methods are intended for samples with an amylose mass fraction > 5% and are widely used in routine food testing and quality control laboratories.

Key topics and requirements

• Scope & applicability
  • For milled, non‑parboiled rice with amylose > 5%.
  • Simplified sample prep commonly used in routine labs; defatting step omitted (unlike the reference method ISO 6647‑1).
• Principle
  • Rice is milled to a fine flour, dispersed in sodium hydroxide, an aliquot is reacted with iodine and the absorbance of the amylose‑iodine complex is measured (typically at 720 nm, also 620 nm or 680 nm may be used).
  • Amylose content is read from a calibration graph prepared using rice standards whose amylose content was determined by the reference method.
• Two dispersion procedures
  • Method A (hot dispersion) - uses 1 mol/L NaOH and a boiling water bath.
  • Method B (cold dispersion) - uses 2 mol/L NaOH and high‑speed magnetic stirring.
• Reagents & apparatus
  • Ethanol (95 %), NaOH at specified concentrations, 1 mol/L acetic acid, fresh iodine/potassium iodide solution.
  • Grinder (to pass 150–180 µm), spectrophotometer (1 cm cells), volumetric flasks, pipettes, analytical balance.
• Calibration & performance
  • Calibration solutions are prepared from rice samples used as standards; calibration and statistical evaluation follow ISO guidance.
  • The document includes precision data (repeatability, reproducibility, interlaboratory test results) and reporting requirements.

Applications & who uses it

• Routine quality control in rice milling and processing plants.
• Food‑testing and analytical laboratories performing compositional analysis.
• Rice breeders and research institutions assessing varietal amylose levels.
• Regulatory bodies, import/export inspection and product specification verification.
• Useful for product labeling, nutritional profiling, and process optimization where amylose content affects cooking/texture.

Related standards

• ISO 6647‑1:2020 - Reference spectrophotometric method with defatting.
• ISO 712 - Determination of moisture content for cereals.
• ISO 7301 - Rice specification.
• ISO 8466‑1 - Calibration and statistical evaluation of analytical methods.

This standard is essential for laboratories seeking a validated, standardized spectrophotometric routine method to measure rice amylose content efficiently and consistently without a defatting step.

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2020
Nadomešča:
SIST EN ISO 6647-2:2015
Riž - Določevanje amiloze - 2. del: Spektrofotometrijska rutinska metoda brez
postopka razmaščevanja in s kalibracijo v skladu s standardi za riž (ISO 6647-
2:2020)
Rice - Determination of amylose content - Part 2: Spectrophotometric routine method
without defatting procedure and with calibration from rice standards (ISO 6647-2:2020)
Reis - Bestimmung des Amylosegehalts - Teil 2: Routinemethode:
Spektrophotometrische Routinemethode ohne Entfettungsverfahren und mit Kalibrierung
nach Reisstandards (ISO 6647-2:2020)
Riz - Détermination de la teneur en amylose - Partie 2: Méthode spectrophotométrique
de routine sans mode opératoire de dégraissage et avec étalonnage à l'aide d'étalons de
riz (ISO 6647-2:2020)
Ta slovenski standard je istoveten z: EN ISO 6647-2:2020
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 6647-2
EUROPEAN STANDARD
NORME EUROPÉENNE
August 2020
EUROPÄISCHE NORM
ICS 67.060 Supersedes EN ISO 6647-2:2015
English Version
Rice - Determination of amylose content - Part 2:
Spectrophotometric routine method without defatting
procedure and with calibration from rice standards (ISO
6647-2:2020)
Riz - Détermination de la teneur en amylose - Partie 2: Reis - Bestimmung des Amylosegehalts - Teil 2:
Méthode spectrophotométrique de routine sans mode Routinemethode: Spektrophotometrische
opératoire de dégraissage et avec étalonnage à l'aide Routinemethode ohne Entfettungsverfahren und mit
d'étalons de riz (ISO 6647-2:2020) Kalibrierung nach Reisstandards (ISO 6647-2:2020)
This European Standard was approved by CEN on 18 July 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 6647-2:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 6647-2:2020) 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 February 2021, and conflicting national standards
shall be withdrawn at the latest by February 2021.
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.
This document supersedes EN ISO 6647-2:2015.
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 6647-2:2020 has been approved by CEN as EN ISO 6647-2:2020 without any
modification.
INTERNATIONAL ISO
STANDARD 6647-2
Third edition
2020-07
Rice — Determination of amylose
content —
Part 2:
Spectrophotometric routine method
without defatting procedure and with
calibration from rice standards
Riz — Détermination de la teneur en amylose —
Partie 2: Méthode spectrophotométrique de routine sans mode
opératoire de dégraissage et avec étalonnage à l'aide d'étalons de riz
Reference number
ISO 6647-2:2020(E)
©
ISO 2020
ISO 6647-2:2020(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: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

ISO 6647-2:2020(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 2
6 Apparatus . 2
7 Sampling . 3
8 Procedure. 3
8.1 Determination of moisture . 3
8.2 Preparation of test sample . 3
8.3 Test portion and preparation of the test solution . 3
8.4 Preparation of the blank solution . 3
8.5 Preparation of the calibration graph . 4
8.5.1 Preparation of the set of calibration solutions . 4
8.5.2 Colour development and spectrophotometric measurements . 4
8.5.3 Plotting the calibration graph . 4
8.6 Determination . 4
9 Expression of results . 4
10 Precision . 5
10.1 Interlaboratory test. 5
10.2 Repeatability . 5
10.3 Reproducibility . 5
11 Test report . 6
Annex A (informative) Results of an interlaboratory test for the routine method .7
Bibliography .11
ISO 6647-2:2020(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).
This third edition cancels and replaces the second edition (ISO 6647-2:2015), which has been technically
revised. The main changes compared with the previous edition are as follows.
— The set of calibration solutions in ISO 6647-2:2015 were made by rice samples analysed by size
exclusion chromatography. In this document, the set of calibration solutions are made by rice
samples analysed by spectrophotometer UV-VIS, without delipidization.
A list of all parts in the ISO 6647 series can be found on the ISO website.
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 6647-2:2020(E)
Rice — Determination of amylose content —
Part 2:
Spectrophotometric routine method without defatting
procedure and with calibration from rice standards
1 Scope
This document specifies two simplified routine methods for the determination of the amylose mass
fraction of milled rice, non-parboiled. The main difference between the two methods is the dispersion
procedure: method A specifies hot dispersion, and method B specifies cold dispersion.
Both methods are applicable to rice with an amylose mass fraction higher than 5 %.
NOTE These methods describe simplified procedures for the preparation of samples, which are frequently
used in routine laboratories. The methods use the same reagents as the reference method (see ISO 6647-1), but
omit the defatting step. Rice samples where the amylose mass fraction has been determined by the reference
method are used as standards.
2 Normative references
The following documents are referred to in the text in such a way that some or 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 712, Cereals and cereal products — Determination of moisture content — Reference method
ISO 6647-1:2020, Rice — Determination of Amylose content — Reference method — Part 1:
Spectrophotometric method with a defatting procedure by methanol and with calibration solutions of potato
amylose and waxy rice amylopectin
ISO 7301, Rice — Specification
ISO 8466-1, Water quality — Calibration and evaluation of analytical methods and estimation of
performance characteristics — Part 1: Statistical evaluation of the linear calibration function
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 6647-1 and ISO 7301 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/
4 Principle
Rice is ground to a very fine flour to break up the endosperm structure in order to aid complete
dispersion and gelatinization. A test portion is dispersed in a sodium hydroxide solution. An aliquot
portion is taken to which is added an iodine solution. The absorbance, at 720 nm, of the colour complex
formed is then determined using a spectrophotometer.
ISO 6647-2:2020(E)
Measurement wavelengths of 620 nm or 680 nm can also be used.
The amylose mass fraction of the sample is then read from a calibration graph, which is prepared by using
rice samples of known amylose mass fraction, determined using the reference method specified above.
...