EN 16378-2013 en Cereals - Determination of impurities content in maize (Zea mays L ) and sorghum (Sorghum bicolor L )《谷物 玉米(玉蜀黍)和高粱(蜀黍)中杂质含量的测定》.pdf

1、BSI Standards PublicationBS EN 16378:2013Cereals Determination ofimpurities content in maize(Zea mays, L.) and sorghum(Sorghum bicolor, L.)BS EN 16378:2013 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 16378:2013.The UK participation in its preparation was ent

2、rusted 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 not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British

3、 Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 77447 8ICS 67.060Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 September 201

4、3.Amendments issued since publicationDate Text affectedBS EN 16378:2013EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16378 August 2013 ICS 67.060 English Version Cereals - Determination of impurities content in maize (Zea mays, L.) and sorghum (Sorghum bicolor, L.) Crales - Dtermination de la

5、 teneur en impurets dans le mas (Zea mays, L.) et le sorgho (Sorghum bicolor, L.) Getreide - Bestimmung von Besatz in Mais (Zea mays, L.) und Hirse (Sorghum bicolor, L.) This European Standard was approved by CEN on 19 July 2013. CEN members are bound to comply with the CEN/CENELEC Internal Regulati

6、ons 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.

7、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 m

8、embers are the national standards bodies of Austria, Belgium, 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, Por

9、tugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All rights of exploitation in any form and by

10、any means reserved worldwide for CEN national Members. Ref. No. EN 16378:2013: EBS EN 16378:2013EN 16378:2013 (E) 2 Contents Page Foreword . 3 1 Scope 4 2 Normative references . 4 3 Terms and definitions 4 4 Principle 6 5 Apparatus and equipment . 6 6 Sampling . 6 7 Procedure . 6 8 Expression of res

11、ults . 7 9 Precision . 8 10 Test report 9 Annex A (informative) Schematic summary on Besatz . 11 Annex B (informative) Diagram of procedure 12 Annex C (informative) Example of calculation . 13 Annex D (informative) Results of interlaboratory tests . 14 Bibliography 19 BS EN 16378:2013EN 16378:2013 (

12、E) 3 Foreword This document (EN 16378:2013) has been prepared 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 endorseme

13、nt, at the latest by February 2014, and conflicting national standards shall be withdrawn at the latest by February 2014. 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 identif

14、ying any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugosla

15、v Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 16378:2013EN 16378:2013 (E) 4 1 Scope This Eu

16、ropean Standard specifies the term Besatz (impurities) and the method for the determination of its components. The term Besatz is used as a parameter for certain quality aspects in maize (Zea mays L.) and sorghum (Sorghum bicolor L.). This method has been validated in an interlaboratory study via th

17、e analysis of samples containing natural amount of impurities, ranging from: 0,0 % to 2,7 % for broken grains; 0,2 % to 3,5 % for grains impurities; 0,5 % to 3,3 % for miscellaneous impurities; 1,8 % to 8,7 % for total impurities. For further information on the validation, see Annex D. 2 Normative r

18、eferences The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applie

19、s. ISO 5223, Test sieves for cereals 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 Besatz all matters of a sample of grain other than the basic cereal of unimpaired quality Note 1 to entry: It comprises the four fractions: broken grains (3.

20、2), grain impurities (3.3), sprouted grains (3.4) and miscellaneous impurities (3.5). Note 2 to entry: The sum of the four fractions is also called Total Besatz. Note 3 to entry: Live pests are not considered as Besatz. They are specified as a separate criterion. Note 4 to entry: A schematic summary

21、 on Besatz is given in Annex A. 3.2 broken grains grains or pieces of grains which pass through a sieve with a circular mesh of: 4,5 mm in diameter for maize; 1,8 mm in diameter for sorghum 3.3 grain impurities elements consisting of other cereals, grains damaged by pests, grains overheated during d

22、rying BS EN 16378:2013EN 16378:2013 (E) 5 3.3.1 other cereals cereal grains and their impurities consisting of grains which do not belong to the species of grain sampled 3.3.2 grains damaged by pests grains which show visible damage owing to attack by insects, rodents, mites or other pests 3.3.3 gra

23、ins overheated by drying grains which have been overheated and have a coloration of the cross section of the germ darker than the colour standard and in which the kernel is sound Note 1 to entry: For determination of such grains, it is recommended to use the colour standard (5.8) to compare with the

24、 colour of the section of the cut germ. 3.4 sprouted grains grains in which the radical or plumule is clearly visible to the naked eye 3.5 miscellaneous impurities elements consisting of extraneous seeds, unsound grains, extraneous matter and impurities of animal origin 3.5.1 extraneous seeds seeds

25、of plants, whether or not cultivated, other than cereals Note 1 to entry: They comprise noxious and non-noxious seeds. The term “noxious seeds” means seeds which are toxic to humans and animals. This group also includes seeds hampering or complicating the cleaning and milling of cereals and seeds af

26、fecting the quality of products processed from cereals. Note 2 to entry: In some cases it may be necessary to distinguish between noxious seeds and non-noxious seeds. An indicative list of noxious seeds is given in ISO 7970:2000, Annex A 5. 3.5.2 unsound grains grains rendered unfit for human consum

27、ption and, as regards feed grain, for feed consumption, owing to putrefaction, mildew, grains affected with fusariosis, or bacterial or other causes Note 1 to entry: Unsound grains also include grains damaged by spontaneous heat generation or too extreme heating during drying which are fully grown g

28、rains in which the tegument is coloured greyish-brown to black while the cross-section of the kernel is coloured-yellowish grey to brownish-black. 3.5.3 extraneous matter all matters in a sample of grains that passing through a sieve with apertures of 1,0 mm are considered extraneous Note 1 to entry

29、: Extraneous matter also includes stones, sand, fragments of straw, cob fragments and similar impurities in the samples which are retained by a sieve with apertures of 1,0 mm. 3.5.4 impurities of animal origin impurities originating from animals such as feathers, hairs, excrements, dead insects and

30、fragment of insects BS EN 16378:2013EN 16378:2013 (E) 6 4 Principle The principle of this method is to separate all the groups of impurities defined in 3.1, from the normal basic grains by sieving and manual selection. 5 Apparatus and equipment 5.1 Sample divider. 5.2 Balance, with a reading accurac

31、y of 0,001 g and capable of weighing to the nearest 0,01 g. 5.3 Sieves, with circular holes of 4,5 mm and 1,8 mm in diameter and slot-widths 1,0 mm 20,0 mm, in accordance with the specifications of ISO 5223. 5.4 Sieving machine, having a rectilinear movement of go and come in the sense of the rectan

32、gular holes. 5.5 Magnifying glass, illuminated. 5.6 Forceps or horn spatula. 5.7 Pots, for retaining components. 5.8 Colour standard, as reference S 3030-Y30R in the Natural Colour System (NCS)1). 6 Sampling It is important that the laboratory receives a sample which is truly representative and has

33、not been damaged or changed during transport and storage. Sampling is not part of the method specified in this European Standard. For information, a recommended sampling procedure is given in EN ISO 24333 1 for the sampling of cereals with constituents distributed uniformly or not uniformly. 7 Proce

34、dure Prepare by division a representative sample of at least (but near) 500 g for maize and 250 g for sorghum. Weigh it to the nearest 0,1 g (a). Pass the sample through the slotted sieve with an aperture of 1,0 mm (5.3), for half a minute. For constant sieving, a sieving machine (5.4) is recommende

35、d. If sieving is performed by hand, it shall consist of horizontal movements parallel to the length of the slots. The matter passed through the 1 mm sieve shall be regarded as extraneous matter. Stones, mud balls, straws, chaff, cob fragments and similar impurities from the over tail of the 1,0 mm s

36、lotted sieve have to be picked out. Both fractions are combined and are regarded as extraneous matter (3.5.3). Weigh them to the nearest 0,1 g (b). Impurities of animal origin should be counted (n), including those which passed through the sieve of 1,00 mm slot-width (5.3). If necessary, a magnifyin

37、g glass should be used. The count of impurities of animal origin (3.5.4) should be quoted separately in numbers per kilogram of maize or sorghum, as appropriate. From the over tails of the 1,0 mm sieve (5.3), prepare, with the aid of a sample divider, a test sample, between 100 g and 200 g for maize

38、 and between 25 g and 50 g for sorghum. Weight this test sample to the nearest 0,01 g (c). 1) The Natural Colour System is defined by the Scandinavian Colour Institute AB, Stockholm (SE). For further explanation see . BS EN 16378:2013EN 16378:2013 (E) 7 Subsequently spread out this partial sample in

39、 a thin layer on a table, and pick out by means of forceps or a horn spatula the element constituting the groups of impurities: other cereals (3.3.1), grains damaged by pests (3.3.2), sprouted grains (3.4), extraneous seeds (3.5.1), unsound grains (3.5.2) and remained extraneous matters (3.5.3). Gra

40、ins whose tegument shows abnormal colour shall be cut longitudinally through the germ. If a major part or the totality of the section of the germ is identical or darker than the colour standard (5.8) then the two halves of the initial grain have to be accounted as grains overheated by drying (3.3.3)

41、. In the case of multiple kinds of damages are observed, the damaged grain shall be added to the fraction with the highest importance for the overall quality. Subsequently sieve the same partial sample through a sieve of 4,5 mm circular holes in diameter for maize or 1,8 mm circular holes in diamete

42、r for sorghum for half a minute. The through of this sieve belong to the group broken grains (3.2). Weigh the clean sample material (d) and all the groups of Besatz to the nearest 0,01 g. If, for a partial sample, the sum of weights for broken grains (3.2), other cereals (3.3.1), grains damaged by p

43、ests (3.3.2), grains overheated during drying (3.3.3), sprouted grains (3.4), extraneous seeds (3.5.1), unsound grains (3.5.2) and extraneous matters (3.5.3) and (d) differs by more than 1 % from (c), the determination shall be invalid and a new partial sample shall be analysed. 8 Expression of resu

44、lts The mass fraction in percent of the Besatz fractions (3.2, 3.3.1, 3.3.2, 3.3.3, 3.4, 3.5.1 and 3.5.2) are calculated as follows: acbaxB100=where B is the mass fraction of Besatz fractions (%); x is the weight of the Besatz group concerned (g); a is the weight of the average sample (g); b is the

45、weight of the extraneous matter on average sample (g); c is the weight of subsample from which Besatz will be removed (g). The mass fraction in percent of extraneous matter (3.5.3) is calculated as follows: abcbaxA1008+ = where A is the percentage of extraneous matter (%); x8is the weight of extrane

46、ous matter of subsample from which Besatz was removed (g); a is the weight of the average sample (g); b is the weight of the extraneous matter of average sample (g); c is the weight of subsample from which Besatz will be removed (g). BS EN 16378:2013EN 16378:2013 (E) 8 The percentage of grains impur

47、ities (3.3) is calculated by adding percentages of other cereals (3.3.1), grains damaged by pests (3.3.2) and grains overheated by drying (3.3.3). The percentage of miscellaneous impurities (3.5) is calculated by adding percentages of extraneous seeds (3.5.1), unsound grains (3.5.2) and extraneous m

48、atters (3.5.3). The percentage of total impurities (3.1) is calculated by adding percentages of broken grains (3.2), grains impurities (3.3), sprouted grains (3.4) and miscellaneous impurities (3.5). The calculation should be carried out to the nearest 0,01 %. In the investigation report, quote to a

49、 precision of 0,1 % for broken grains (3.2), grains impurities (3.3), sprouted grains (3.4) and miscellaneous impurities (3.5) and to a precision of 0,01 % for all sub components of these categories. Report the impurities of animal origin (3.5.4) in number per kilogram of grain. An example of calculation is given in Annex C. 9 Precision 9.1 General Details of an international inter-laboratory test on the precision of the method are summarised in Annex D. The values derived from this test may not be applicable to concentra