1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 520:2010Cereals and pulses Determination of the mass of1000 grains (ISO 520:2010)BS EN ISO 520:2010 BRITISH STANDARDNational forewordThis British Standard is the UK imp
2、lementation of EN ISO 520:2010. Itsupersedes BS 4317-1:1980 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee AW/4, Cereals and pulses.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does n
3、ot purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010 ISBN 978 0 580 66195 2 ICS 67.060 Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the
4、Standards Policy and Strategy Committee on 31 December 2010. Amendments issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 520 November 2010 ICS 67.060 English Version Cereals and pulses - Determination of the mass of 1000 grains (ISO 520:201
5、0) Crales et lgumineuses - Dtermination de la masse de 1000 grains (ISO 520:2010) Getreide und Hlsenfrchte - Bestimmung der 1 000-Korn-Masse (ISO 520:2010) This European Standard was approved by CEN on 13 November 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which
6、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 Europ
7、ean 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
8、 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, Romania, Slovakia, Slovenia, Spain, Sweden
9、, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Re
10、f. No. EN ISO 520:2010: EBS EN ISO 520:2010 EN ISO 520:2010 (E) 3 Foreword This document (EN ISO 520:2010) 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. T
11、his 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 May 2011, and conflicting national standards shall be withdrawn at the latest by May 2011. Attention is drawn to the possibility that some of the ele
12、ments 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/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this E
13、uropean 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland an
14、d the United Kingdom. Endorsement notice The text of ISO 520:2010 has been approved by CEN as a EN ISO 520:2010 without any modification. BS EN ISO 520:2010ISO 520:2010(E) ISO 2010 All rights reserved iiiForeword ISO (the International Organization for Standardization) is a worldwide federation of n
15、ational 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. Inter
16、national 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. International Standards are drafted in accordance with the
17、 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 committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by
18、 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 held responsible for identifying any or all such patent rights. ISO 520 was prepared by Technical Committee ISO/T
19、C 34, Food products, Subcommittee SC 4, Cereals and pulses. This second edition cancels and replaces the first edition (ISO 520:1977), which has been technically revised. BS EN ISO 520:2010BS EN ISO 520:2010INTERNATIONAL STANDARD ISO 520:2010(E) ISO 2010 All rights reserved 1Cereals and pulses Deter
20、mination of the mass of 1000 grains 1 Scope This International Standard specifies a method for the determination of the mass of 1 000 grains of cereals and pulses. This International Standard is applicable to all species of cereals and pulses with the exception of seed lots for sowing purposes. 2 No
21、rmative references The following referenced documents are indispensable for the application 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 pr
22、oducts Determination of moisture content Reference method ISO 24557, Pulses Determination of moisture content Air-oven method 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 mass of 1 000 grains as received mass of 1 000 grains including the
23、moisture content at the time of the determination 3.2 mass of 1 000 grains on the dry matter basis mass of 1 000 grains as received converted to the dry matter basis by correcting for the moisture content at the time of the determination 4 Principle A test portion is prepared by separating whole gra
24、ins. The test portion is weighed and the whole grains counted. The mass of the whole grains is divided by their number, and expressed on the basis of 1 000 grains. BS EN ISO 520:2010ISO 520:2010(E) 2 ISO 2010 All rights reserved5 Apparatus 5.1 Sample divider apparatus (if necessary). 5.2 Appropriate
25、 apparatus for counting grains (e.g. a photoelectric counter). If suitable apparatus is not available, counting may be carried out by hand. 5.3 Balance, capable of being read to the nearest 0,001 g. 6 Procedure 6.1 Determination of the mass of 1 000 grains as received Take by division a mass consist
26、ing of approximately 500 grains from the sample as received. Separate the whole grains, weigh them to the nearest 0,01 g and count them. For straw cereals, a mass of 30 g is generally in accordance with this instruction. Carry out tests in duplicate. 6.2 Determination of the mass of 1 000 grains on
27、the dry matter basis If the mass of 1 000 grains is to be referred to the dry basis, determine the moisture content of the whole grains free of impurities in a separate sample, in accordance with the reference method specified in ISO 712 for cereals and ISO 24557 for pulses. 7 Expression of results
28、7.1 The mass of 1 000 grains as received, m1, in grams, is given by the equation: t11000mmN= where mtis the mass, in grams, of the whole grains in the test portion; N is the number of whole grains in the test portion. 7.2 The mass of 1 000 grains on the dry matter basis, m0, in grams, is given by th
29、e equation: ()21H0100100mwm=Owhere m1is the mass, in grams, of the 1 000 grains as received; wH2Ois the moisture content, expressed as a percentage mass fraction, of the grains as received. 7.3 Take as the result the arithmetic mean of the duplicate tests, provided that the requirement concerning re
30、peatability (see 8.2) is satisfied. BS EN ISO 520:2010ISO 520:2010(E) ISO 2010 All rights reserved 3If not, make a new determination and take the average of the test results in the second determination, provided that the requirement concerning repeatability (see 8.2) is satisfied. Express the result
31、, indicating the mass of 1 000 grains, in grams: a) to the second decimal place, if the mass is below 10 g; b) to the first decimal place, if the mass is 10 g or more but does not exceed 100 g; c) as a whole number, if the mass exceeds 100 g. 8 Precision 8.1 Interlaboratory test Details of an interl
32、aboratory test on the precision of the method are summarized in Annex A. The values derived from this interlaboratory test cannot be applied to other concentration ranges and matrices than those given. 8.2 Repeatability The absolute difference between two independent single test results, obtained us
33、ing the same method on identical test material in the same laboratory by the same operator using the same equipment within a short interval of time, will not in more than 5 % of cases be greater than the repeatability limit r = sr 2,77 r = 0,45 2,77 = 1,3 for products whose mass of 1 000 grains on t
34、he dry matter basis lies between 29,8 g and 48,2 g (see Tables A.1 and A.2, and Figure A.1). 8.3 Reproducibility The absolute difference between two single test results, obtained using the same method on identical test material in different laboratories with different operators using different equip
35、ment, will not in more than 5 % of cases be greater than the reproducibility limit R = sR 2,77 R = 0,82 2,77 = 2,3 for products whose mass of 1 000 grains on the dry matter basis lies between 29,8 g and 48,2 g (see Tables A.1 and A.2, and Figure A.2). 8.4 Comparison of two groups of measurements in
36、one laboratory Critical difference (CD) is the difference between two averaged values obtained from two test results under repeatability conditions. As the result is a mean of two values (see 7.1), the comparison of mass of 1 000 grains shall be made with critical difference. BS EN ISO 520:2010ISO 5
37、20:2010(E) 4 ISO 2010 All rights reservedThe CD between two averaged values obtained from two test results under repeatability conditions is equal to: 1211 12,8 2,8 1,98 0,89 0,922 2rrrsssnn+= = = where sris the standard deviation of repeatability; n1, n2are the number of test results corresponding
38、to each of the averaged values (in the above example n1= n2= 2). 8.5 Comparison of two groups of measurements in two laboratories The CD between two averaged values obtained in two different laboratories from two test results under repeatability conditions is equal to: 22 2 212112,8 1 2,8 0,5 2,12 2
39、,122Rr R rss s snn = =where sris the standard deviation of repeatability; sRis the standard deviation of reproducibility; n1, n2are the number of test results corresponding to each of the averaged values (in the above example n1= n2= 2). 8.6 Expanded uncertainty Expanded uncertainty, U, is a paramet
40、er representing the distribution of the values which may reasonably be attributed to the result. This uncertainty is given by a statistical distribution of the results from the interlaboratory test and is characterized by the experimental standard deviation. For mass of 1 000 grains on dry matter ba
41、sis, the expanded uncertainty is given by U = 2sR= 1,6 where sRis the reproducibility standard deviation given in 8.3. 9 Note on procedure 9.1 Samples containing decorticated and non-decorticated grains If the sample contains a mixture of decorticated and non-decorticated grains, the two kinds shall
42、 be treated and counted separately. 9.2 Samples containing twin oat grains Twin oat grains shall be separated from one another and counted as two grains. BS EN ISO 520:2010ISO 520:2010(E) ISO 2010 All rights reserved 510 Test report The test report shall contain at least the following information: a
43、) all information necessary for complete identification of the sample; b) the sampling method used, if known; c) the test method used, with reference to this International Standard (ISO 520:2010); d) all operating details not specified in this International Standard, or regarded as optional, togethe
44、r with details of any incidents which may have influenced the test result(s); e) the test result(s) obtained; f) details of whether a retest was necessary. BS EN ISO 520:2010ISO 520:2010(E) 6 ISO 2010 All rights reservedAnnex A (informative) Results of the interlaboratory test The repeatability, rep
45、roducibility, and critical difference of the method were established by statistical treatment of data obtained during a monthly proficiency test organized by BIPEA (FR) over 10 months. The calculations were performed in accordance with the requirements of ISO 5725-31and ISO 5725-62. Participating la
46、boratories numbered 11 in a test on durum wheat and eight on barley. Of each species, 10 samples were analysed. The statistical results of the study are presented in Tables A.1 and A.2, and in Figures A.1 and A.2. Table A.1 Statistical results of the inter-laboratory test on durum wheat Parameters D
47、urum wheat 1 Durum wheat 2 Durum wheat 3 Durum wheat 4Durum wheat 5Durum wheat 6Durum wheat 7Durum wheat 8 Durum wheat 9 Durum wheat 10 Number of participating laboratories after eliminating outliers 9 10 12 11 11 11 11 12 11 12 Mean value, 1,m g 33,45 34,57 35,01 37,97 38,24 40,02 40,16 40,64 41,22
48、 48,20 Repeatability standard deviation, sr, g 0,20 0,28 0,37 0,30 0,18 0,40 0,35 0,44 0,45 0,26 Coefficient of variation of repeatability, CV,r, % 0,60 0,80 1,06 0,78 0,46 0,99 0,87 1,08 1,10 0,53 Repeatability limit, r (2,8 sr), g 0,56 0,76 1,01 0,82 0,49 1,10 0,97 1,22 1,26 0,71 Reproducibility s
49、tandard deviation, sR, g 0,47 0,75 0,55 0,44 0,34 0,51 0,61 0,48 0,79 0,32 Coefficient of variation of reproducibility, CV,R, % 1,40 2,16 1,57 1,16 0,89 1,27 1,53 1,18 1,90 0,67 Reproducibility limit, R (2,8 sR), g 1,30 2,07 1,52 1,22 0,94 1,41 1,70 1,33 2,18 0,89 BS EN ISO 520:2010ISO 520:2010(E) ISO 2010 All rights reserved 7Table A.2 Statistical results of the inter-laboratory test on barley Parameters Barley 1 Barley 2 Barley 3 Barley 4 Barley 5 Barley 6 Barley 7 Barley 8 Barley 9 Barley 10 Nu
