1、BSI Standards PublicationBS EN ISO 17715:2014BS I : 3Flour from wheat (Triticumaestivum L.) Amperometricmethod for starch damagemeasurementBS EN ISO 17715:2014 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 17718:2014. It is identical to ISO 17715:2013. It
2、supersedes BS ISO 17715:2013, which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee AW/4, Cereals and pulses.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all t
3、he necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2015. Published by BSI Standards Limited 2015ISBN 978 0 580 86714 9ICS 67.060Compliance with a British Standard cannot confer immunity from legal obligations.This British Stand
4、ard was published under the authority of the Standards Policy and Strategy Committee on 28 February 2013.Amendments/corrigenda issued since publicationDate Text affected31 January 2015 This corrigendum renumbers BS ISO 17715:2013 as BS EN ISO 17715:2014. EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE
5、NORM EN ISO 17715 December 2014 ICS 67.060 English Version Flour from wheat (Triticum aestivum L.) - Amperometric method for starch damage measurement (ISO 17715:2013) Farine de bl tendre (Triticum aestivum L.) - Mthode ampromtrique pour le mesurage de lendommagement de lamidon (ISO 17715:2013) Weiz
6、enmehl (Triticum aestivum L.) - Messung der Strkebeschdigung mittels amperometrischer Methode (ISO 17715:2013) This European Standard was approved by CEN on 16 December 2014. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this Euro
7、pean 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 version
8、s (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, Be
9、lgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Swit
10、zerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN nation
11、al Members. Ref. No. EN ISO 17715:2014 EBS EN ISO 17715:2014EN ISO 17715:2014 (E)EN ISO 17715:2014 (E) 3 Foreword The text of ISO 17715:2013 has been prepared by Technical Committee ISO/TC 34 “Food products” of the International Organization for Standardization (ISO) and has been taken over as EN IS
12、O 17715:2014 by 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 June 2015, and conflicting na
13、tional standards shall be withdrawn at the latest by June 2015. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN-C
14、ENELEC 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary,
15、 Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 17715:2013 has been approved by CEN as EN ISO 17715:2014 without any modif
16、ication. BS EN ISO 17715:2014ISO 17715:2013(E)BS ISO 17715:2013 ISO 2013 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope . 12 Terms and definitions . 13 Principle 14 Reagents 15 Equipment . 26 Sampling 27 Procedure. 27.1 Reagent weighing and dissolution . 27.2 Sample weighing .
17、27.3 Test 27.4 Cleaning . 37.5 Number of determinations . 38 Expression of results 39 Precision . 39.1 Interlaboratory tests 39.2 Repeatability limits, r .39.3 Reproducibility limits, R 49.4 Critical difference, dC49.5 Uncertainty, u 510 Test report . 5Annex A (informative) Data from interlaboratory
18、 tests on wheat flour 6Bibliography .13BS ISO 17715:2013ISO 17715:2013(E) ISO 2013 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope . 12 Terms and definitions . 13 Principle 14 Reagents 15 Equipment . 26 Sampling 27 Procedure. 27.1 Reagent weighing and dissolution .7.2 Sample wei
19、ghing .7.3 Test 7.4 Cleaning . 37.5 Number of determinations .8 Expression of results 39 Precision . 39.1 Interlaboratory tests 9.2 Repeatability limits, r .9.3 eproducibility limits, R 49.4 Critical difference, dC9.5 Uncertainty, u 510 Test report . 5Annex A (informative) Data from interlaboratory
20、tests on wheat flour 6Bibliography .13ivBS ISO 17715:2013ISO 17715:2013(E)ForewordISO (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 tec
21、hnical 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 closel
22、y 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 In
23、ternational 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 m
24、ay be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 17715 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 4, Cereals and pulses.iv ISO 2013 All rights reservedBS ISO 17715:2013ISO 17715:2013(E)Introduct
25、ionDamaged starch content is an important parameter in flour quality as it dir ctly impacts the flour water absorption capacity and therefore its use in the agri-food industry.In the past, a number of methods based on various principles were developed to estimate such content, but comparing the resu
26、lts is difficult due to the different principles and units of measurement used.A laboratory device is dedicated to the determination of damaged starch content using an amperometric method and which offers a choice of units of measurement according to individual references. ISO 2013 All rights reserv
27、ed vBS EN ISO 17715:2014Flour from wheat (Triticum aestivum L.) Amperometric method for starch damage measurement1 ScopeThis International Standard specifies the determination of the damage to starch using an amperometric method.It is applicable to all flour samples from industrial or laboratory mil
28、ling of wheat (Triticum aestivum L.).NOTE 1 Wheat can be milled in the laboratory according to the methods described in ISO 279719or in BIPEA guidance document BY.102.D.9302.10NOTE 2 In the absence of validity studies, the results on semi-wholemeal or wholemeal flour, although able to meet the condi
29、tions of repeatability given in Clause 9, require careful interpretation.2 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.2.1damaged starchstarch granules present in wheat flour mechanically damaged during milling, leading to a greater capacity to a
30、bsorb water and increasing susceptibility to amylolytic enzymesNote 1 to entry: Too high a damaged starch content has a negative effect on quality of flours.3 PrincipleDetermination of damaged starch content of a flour sample by measurement of iodine absorption kinetics in an aqueous medium using an
31、 amperometric electrode.The amperometric method is based on the existing proportionality between iodine absorption capacity and starch damage content.4 ReagentsUse only reagents of recognized analytical grade, unless otherwise specified.4.1 Water, osmosed or demineralized or at least equivalent grad
32、e.4.2 Boric acid or citric acid, powdered, for testing.WARNING The use of boric acid involves hazardous operations. This document does not purport to address all the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health prac
33、tices and to ensure complaince with any national regulatory conditions.4.3 Potassium iodide, powdered, for testing.4.4 Sodium thiosulfate, solution in water at 0,1 mol/l prepared from a ready-to-use vial containing 0,1 mol sodium thiosulfate, to be diluted with water (4.1) in a 1 l flask. Powdered s
34、odium thiosulfate can INTERNATIONAL STANDARD BS EN ISO 17715:2014ISO 17715:2013(E) ISO 2013 All rights reserved 1also be used where the concentration of the final solution is 0,1 mol/l. Protect the solution from light and use within 3 months.5 EquipmentUsual laboratory apparatus and, in particular,
35、the following.5.1 Chopin SDmatic,1)equipped with a reaction vessel and sample holder.NOTE This International Standard has been developed using the Chopin SDmatic.1)It does not apply to the SD4 Chopin and Rapid FT devices which also measure damaged starch content, but using different technology.5.2 L
36、aboratory scales, with a display accuracy of 102g enabling weighing at 101g accuracy.5.3 Laboratory scales, with a display accuracy of 104g enabling weighing at 103g accuracy.5.4 Piston distributor, delivering 120 ml distilled water to the nearest 0,5 ml.5.5 One-mark volumetric flask, capacity 1 000
37、 ml, ISO 1042,2class A.6 SamplingSampling is not part of the method specified in this International Standard. A recommended sampling method is given in ISO 24333.8It is important the laboratory receive a truly representative sample which has not been damaged or changed during transport or storage.7
38、Procedure7.1 Reagent weighing and dissolutionWeigh (5.2), to the nearest 0,5 g, 3,0 g boric acid (4.2) or 1,5 g citric acid (4.2) and 3,0 g (4.3) potassium iodide and add to a clean and dry reaction vessel (5.1). Add one drop (about 0,04 ml) of sodium thiosulfate solution (4.4) and dispense (5.4) 12
39、0 ml distilled water (4.1) into the vessel.As the test begins with a heating and stirring phase, it is not necessary to obtain full dissolution of the reagents at this stage. In order to minimize losses during transfer, add powdered reagents directly to the reaction vessel.7.2 Sample weighingWeigh (
40、5.3), to the nearest 103g, 1,000 g 0,100 g of the test sample of flour and place it in the pre-cleaned sample holder (5.1).7.3 TestPlace the reaction vessel in the well on the device.Lower the head of the device, and insert the sample holder containing the flour (7.2) into the compartment.1) Chopin
41、SDmaticis the trade name of a product supplied by Chopin Technologies. This information is given forthe convenience of users of this document and does not constitute an endorsement by ISO of the product named. Equivalent products may be used if they can be shown to lead to the same results.BS EN ISO
42、 17715:2014ISO 17715:2013(E) 2 ISO 2013 All rights reservedBS EN ISO 17715:2014ISO 17715:2013(E) Start the test. Indicate the exact mass of the test portion of flour weighed to the nearest 0,001 g. It is also possible to indicate the water and protein content of the sample if a result corrected on t
43、his basis is to be obtained, otherwise the default values should be left (mass fractions of 14 % and 12 %, respectively) for the two components. Confirm the start of the test.The test lasts 6 min to 7 min. Ensure that all of the flour descends into the reaction vessel when the vibrator starts up. Us
44、e the tip of a brush or lightly blow to enable any remaining flour to fall.Wait for the beep at the end of the test at which point the result is displayed.7.4 CleaningRaise the head of the device and remove the reaction vessel. Rinse, then carefully and gently wipe the measuring electrode, the heati
45、ng element and the stirrer.Remove any residue from the vessel (do not dispose of in the sink). Carefully wash and wipe dry the reaction vessel, which shall be free of all traces of reagent, sample or moisture, and which shall be left ready for use in a later test.7.5 Number of determinationsPerform
46、two determinations on the same test sample.8 Expression of resultsThe result is expressed as AI% (iodine absorption percentage) converted into UCD (ChopinDubois units). Equations provided by the manufacturer can be used to calculate the equivalence in another unit.The arithmetic mean of the two dete
47、rminations (7.5) shall be taken as the result if they meet the conditions of repeatability specified in 9.2 or in Table A.5. Otherwise, perform two new determinations.NOTE It can be useful to calculate starch damage on a constant water and protein content basis. In this case, flour moisture content
48、and protein content can be determined in accordance with ISO 7121for moisture and ISO 204837or ISO/TS 16634-26for protein.9 Precision9.1 Interlaboratory testsTwo interlaboratory tests established the repeatability and reproducibility limits of the method. The statistical results of the study are giv
49、en in Annex A.The values of each of the studies apply to the concentration ranges and flours from wheat (Triticum aestivum L.).9.2 Repeatability limits, rRepeatability limit is the value below which the absolute value, of the difference between two test results obtained in conditions of repeatability is located, with a probability of 95 %.The repeatability limits, r, are obtained from Formulae (1) and (2). Some repeatability limit values are listed in Table A.5.For AI%:rA= +()0 007 0 787128,%I (1)where AI%is the mean
