1、March 2011 Translation by DIN-Sprachendienst.English price group 10No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS
2、67.060!$ng“1752568www.din.deDDIN EN ISO 520Cereals and pulses Determination of the mass of 1 000 grains (ISO 520:2010)English translation of DIN EN ISO 520:2011-03Getreide und Hlsenfrchte Bestimmung der 1 000-Korn-Masse (ISO 520:2010)Englische bersetzung von DIN EN ISO 520:2011-03Crales et lgumineus
3、es Dtermination de la masse de 1 000 grains (ISO 520:2010)Traduction anglaise de DIN EN ISO 520:2011-03www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.1503.11 DIN EN ISO 520:2011-03 2 A comma is used as the decimal marker. National
4、 foreword This standard has been prepared by Technical Committee ISO/TC 34 “Food products” (Secretariat: AFNOR, France), Subcommittee SC 4 “Cereals and pulses” (Secretariat: SAC, China) in collaboration with Technical Committee CEN/TC 338 “Cereal and cereal products” (Secretariat: AFNOR, France), in
5、 accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement). The responsible German body involved in its preparation was the Normenausschuss Lebensmittel und landwirtschaftliche Produkte (Food and Agricultural Products Standards Committee), Working Committee NA 057
6、-05-06 AA Getreide und Getreideerzeugnisse. The DIN Standard corresponding to the International Standard referred to in this document is as follows: ISO 712 DIN EN ISO 712 National Annex NA (informative) Bibliography DIN EN ISO 712, Cereals and cereal products Determination of moisture content Refer
7、ence method EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 520 November 2010 ICS 67.060 English Version Cereals and pulses Determination of the mass of 1 000 grains (ISO 520:2010) Crales et lgumineuses Dtermination de la masse de 1 000 grains (ISO 520:2010) Getreide und Hlsenfrchte Bestimm
8、ung 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 stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
9、 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 tr
10、anslation 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, Fin
11、land, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES
12、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. Ref. No. EN ISO 520:2010: EContents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Pri
13、nciple4 5 Apparatus .5 6 Procedure .5 6.1 Determination of the mass of 1 000 grains as received 5 6.2 Determination of the mass of 1 000 grains on the dry matter basis 5 7 Expression of results 5 8 Precision.6 8.1 Interlaboratory test 6 8.2 Repeatability.6 8.3 Reproducibility.6 8.4 Comparison of two
14、 groups of measurements in one laboratory6 8.5 Comparison of two groups of measurements in two laboratories.7 8.6 Expanded uncertainty .7 9 Note on procedure.7 9.1 Samples containing decorticated and non-decorticated grains.7 9.2 Samples containing twin oat grains 7 10 Test report 8 Annex A (informa
15、tive) Results of the interlaboratory test 9 Bibliography 13 EN ISO 520:2010 (E) DIN EN ISO 520:2011-03 2 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 s
16、ecretariat 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 May 2011, and conflicting national standards shall be withdrawn at the latest by May 2011. Attention is drawn
17、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/CENELEC Internal Regulations, the national standards organizations of the following
18、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, Romania, Slovakia,
19、Slovenia, Spain, Sweden, Switzerland and 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. EN ISO 520:2010 (E) DIN EN ISO 520:2011-03 3 1 Scope This International Standard specifies a method for the determination o
20、f 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 Normative references The following referenced documents are indispensable for the application of this document. For
21、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 24557, Pulses Determination of moisture content Air-
22、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 moisture content at the time of the determination 3.2 mass of 1 000 grains on the dry matter basis mass of 1 000 g
23、rains 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 grains. The test portion is weighed and the whole grains counted. The mass of the whole grains is divided by their nu
24、mber, and expressed on the basis of 1 000 grains. EN ISO 520:2010 (E) DIN EN ISO 520:2011-03 4 5 Apparatus 5.1 Sample divider apparatus (if necessary). 5.2 Appropriate apparatus for counting grains (e.g. a photoelectric counter). If suitable apparatus is not available, counting may be carried out by
25、 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 consisting of approximately 500 grains from the sample as received. Separate the whole grains, weigh them to the nearest 0,01 g and count th
26、em. 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 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 grai
27、ns 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 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 wh
28、ole 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 the equation: ()21H0100100mwm=Owhere m1is the mass, in grams, of the 1 000 grains as received; wH2Ois the moisture content, expressed a
29、s 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 repeatability (see 8.2) is satisfied. EN ISO 520:2010 (E) DIN EN ISO 520:2011-03 5 If not, make a new determination and take the averag
30、e of the test results in the second determination, provided that the requirement concerning repeatability (see 8.2) is satisfied. Express the result, 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 i
31、s 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 interlaboratory test on the precision of the method are summarized in Annex A. The values derived from this interlaboratory test cannot be applied to other co
32、ncentration ranges and matrices than those given. 8.2 Repeatability The absolute difference between two independent single test results, obtained using 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, wil
33、l 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 the 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 sin
34、gle test results, obtained using the same method on identical test material in different laboratories with different operators using different equipment, 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 grai
35、ns 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 one laboratory Critical difference (CD) is the difference between two averaged values obtained from two test results under repeatability conditions. As
36、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. EN ISO 520:2010 (E) DIN EN ISO 520:2011-03 6 The CD between two averaged values obtained from two test results under repeatability conditions is equal to: 1211 12,8 2,8 1,98 0
37、,89 0,922 2rrrsssnn+= = = where sris the standard deviation of repeatability; n1, n2are the number of test results corresponding 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 obtain
38、ed 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 2,122Rr R rss s snn = =where sris the standard deviation of repeatability; sRis the standard deviation of reproducibility; n1, n2are the number of test results correspondin
39、g to each of the averaged values (in the above example n1= n2= 2). 8.6 Expanded uncertainty Expanded uncertainty, U, is a parameter 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 fro
40、m the interlaboratory test and is characterized by the experimental standard deviation. For mass of 1 000 grains on dry matter basis, 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 decortica
41、ted and non-decorticated grains If the sample contains a mixture of decorticated and non-decorticated grains, the two kinds shall 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. EN ISO 520:2010 (
42、E) DIN EN ISO 520:2011-03 7 10 Test report The test report shall contain at least the following information: a) 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:
43、2010); d) all operating details not specified in this International Standard, or regarded as optional, together 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. EN ISO 520:2010 (E) DIN EN ISO 520
44、:2011-03 8 Annex A (informative) Results of the interlaboratory test The repeatability, reproducibility, 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 pe
45、rformed in accordance with the requirements of ISO 5725-31and ISO 5725-62. Participating laboratories 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
46、A.2. Table A.1 Statistical results of the inter-laboratory test on durum wheat Parameters Durum 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 1
47、1 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 48,20 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 Repeatabili
48、ty 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 standard 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 s
49、R), g 1,30 2,07 1,52 1,22 0,94 1,41 1,70 1,33 2,18 0,89 EN ISO 520:2010 (E) DIN EN ISO 520:2011-03 9 Table 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 Number of participating laboratories after eliminating outliers 7 7 8 6 8 8 8 8 7 8 Mean value, 1,m g 29,79 35,12 35,85 35,89 36,34 36,72 36,84 36,9 38,89 40,58 Repeatability standard deviation, sr,g 0,14 0,14 0,22 0,16 0,25 0,30 0,31 0,15 0,11
