1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 4150:2011Green coffee or raw coffee Size analysis Manual andmachine sievingBS ISO 4150:2011 BRITISH STANDARDNational forewordThis British Standard is the UK implementation
2、 of ISO 4150:2011. Itsupersedes BS5752-5:1991 (R96) which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee AW/15, Coffee.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to inclu
3、de all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580 66461 8ICS 67.140.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This Britis
4、h Standard was published under the authority of theStandards Policy and Strategy Committee on 29 February 2012.Amendments issued since publicationDate Text affectedBS ISO 4150:2011Green coffee or raw coffee Size analysis Manual and machine sievingCaf vert Analyse granulomtrique Tamisage manuel et la
5、 machine ISO 2011Reference numberISO 4150:2011(E)Third edition2011-11-15ISO4150INTERNATIONAL STANDARDBS ISO 4150:2011ISO 4150:2011(E)COPYRIGHT PROTECTED DOCUMENT ISO 2011All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any m
6、eans, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrigh
7、tiso.orgWeb www.iso.orgPublished in Switzerlandii ISO 2011 All rights reservedBS ISO 4150:2011ISO 4150:2011(E) ISO 2011 All rights reserved iiiContents PageForeword iv1 Scope 12 Normative references .13 Terms and definitions .14 Principle .15 Apparatus 16 Sampling .27 Procedure 37.1 Test portion .37
8、.2 Selection of sieves 37.3 Sieving and weighing .37.4 Additional observations 38 Statement of results .49 Precision 49.1 General .49.2 Repeatability .49.3 Reproducibility .410 Test report .4Annex A (normative) Characteristics of perforated metal plate test sieves with round holes 6Annex B (normativ
9、e) Characteristics of perforated metal plate test sieves with slotted apertures 8Annex C (informative) Interlaboratory .9Annex D (informative) Verification of mechanical equipment of sieving machines .10Bibliography .12BS ISO 4150:2011ForewordISO (the International Organization for Standardization)
10、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 repres
11、ented 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.International Standards are d
12、rafted 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 International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International S
13、tandard 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 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 4150 was prepared b
14、y Technical Committee ISO/TC 34, Food products, Subcommittee SC 15, Coffee.This third edition cancels and replaces the second edition (ISO 4150:1991), which has been technically revised.ISO 4150:2011(E)iv ISO 2011 All rights reservedBS ISO 4150:2011INTERNATIONAL STANDARD ISO 4150:2011(E)Green coffee
15、 or raw coffee Size analysis Manual and machine sieving1 ScopeThis International Standard specifies a routine method for carrying out size analysis of green coffee by manual and machine sieving using laboratory test sieves.2 Normative referencesThe following referenced documents are indispensable fo
16、r 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 3, Preferred numbers Series of preferred numbersISO 2395, Test sieves and test sieving VocabularyISO
17、2591-1, Test sieving Part 1: Methods using test sieves of woven wire cloth and perforated metal plateISO 3310-2, Test sieves Technical requirements and testing Part 2: Test sieves of perforated metal plateISO 3509, Coffee and coffee products VocabularyISO 4072, Green coffee in bags Sampling3 Terms a
18、nd definitionsFor the purposes of this document, the terms and definitions given in ISO 2395 (for test sieves) and ISO 3509 (for coffee) apply.4 PrincipleA laboratory sample is separated into fractions according to size by manual (or machine) sieving, and the results are expressed as percentage mass
19、 fractions.5 Apparatus5.1 Balance, capable of weighing to the nearest 0,1 g.5.2 Nest of test sieves.For the dimensions and sieving medium, the test sieves shall have a sieve surface area of between 550 cm2and 1 000 cm2. Suitable test sieves are, for example, square sieves of size 300 mm, complying w
20、ith the requirements of ISO 2591-1, except that the approximate depth of the sieve may be reduced to 25 mm.The perforated metal plate used as the sieving medium shall be made of metal of suitable strength, such as stainless steel, ordinary steel or zinc, 0,8 mm to 1 mm thick. Each plate shall be per
21、forated in accordance with the requirements given in Annex A or Annex B.The test sieves shall be marked by means of a label attached to the sieve giving the following details:a) traditional numbering (see Annex A); ISO 2011 All rights reserved 1BS ISO 4150:2011NOTE The traditional numbering is given
22、 for information purposes. It corresponds to the nominal aperture size of round apertures or to the width of slotted apertures, expressed in 64ths of an inch, closest to the metric dimension adopted.b) nominal aperture size or the dimensions of slotted apertures (see Annex B);c) in the case of round
23、 holes, the diameter of the sieve current is determined in the verification (see Annex A);d) reference to the International Standard(s) with which the sieve complies;e) material of the sieving medium and that of the frame;f) name of the firm (manufacturer or vendor) taking responsibility for the sie
24、ve;g) identification number.In terms of construction, the test sieve frames shall nest snugly with each other and with the lid and receiver.The frame shall be smooth and the seal of the sieve so constructed as to prevent lodging of the coffee beans being sieved.For verification, new test sieves shal
25、l be tested (for example using the methods described in ISO 3310-2) and a certificate shall be available to this effect. Periodic checking should also be performed, since some changes in the dimensions of the apertures can occur after a period of use.5.3 Test sieves. 5.3.1 Test sieves with round hol
26、es, 11 sieves (see Annex A).5.3.2 Test sieves with slotted holes, 7 sieves (see Annex B).5.4 Lid.The lid shall comply with the requirements of ISO 2591-1.5.5 Receiver.The receiver shall comply with the requirements of ISO 2591-1.5.6 Machine for sieving, having the following features.a) The results o
27、btained over each sieve shall be equal to using the manual method. In Annex D, a guide is presented to carry out this verification.b) The machine shall contain a tray to allow for the assembly of a set with any number of sieves in order to carry out a complete analysis.c) It shall consist of sieves
28、which are easy to fix.d) It shall have an adjustable timer in the 0 min to 3 min range.6 Sampling Take a laboratory sample of 300 g, prepared in accordance with ISO 4072.NOTE The same laboratory sample as used for the examination and determination described in ISO 4149 can be used for the purposes o
29、f this International Standard, provided the sample is fully reconstituted before the test portion is taken for the test sieving.ISO 4150:2011(E)2 ISO 2011 All rights reservedBS ISO 4150:20117 Procedure7.1 Test portionWeigh, to the nearest 0,1 g, 300 g of the laboratory sample.7.2 Selection of sieves
30、Select a nest of sieves (5.2) with round apertures (5.3.1). Assemble the sieves in descending order of aperture size. If dealing with a sample of substantially peaberry coffee, to determine the percentage mass fraction of peaberry in the test portion, use a sieve with slotted openings (5.3.2). Disca
31、rd the sieves with larger apertures through which all beans can pass.NOTE The common sieve numbers are 18, 17, 16, 15, 14 and 12.Place the receiver (5.5) under the sieve with the smallest apertures.7.3 Sieving and weighingPour the test portion (7.1) on to the upper sieve and put the lid (5.4) in pla
32、ce.7.3.1 Manual sieving 7.3.1.1 Spread a clean, dry, soft cloth under the receiver, in order to obtain smooth sliding.Spread the cloth (see 7.2) over a flat surface and then put the nest of sieves on it.7.3.1.2 Agitate uniformly the nest of sieves for 3 min, one way (back and forth) without raising
33、it from the surface at a speed of between 110 cycles per min and 130 cycles per min with a displacement of 10 cm approximately.NOTE A speed with 150 cycles per min and 160 cycles per min and a displacement of 5 cm can be used.If using slotted aperture sieves, agitate in a direction parallel to the l
34、ength of apertures. Beans remaining in apertures shall be considered to be retained on the sieve in question.Remove all the beans from each sieve separately, to avoid loss of the beans. Put the lid on the top of the respective sieve, then put one hand under the sieve and push the beans up. Then, car
35、efully place the beans on a tray.7.3.1.3 Weigh to the nearest 0,1 g, the beans collected on each of the sieves used and in the receiver.7.3.2 Machine sieving7.3.2.1 Put the nest of sieves on the machine (5.6) firmly, and turn the equipment on for 3 min. If using slotted aperture sieves, agitate in a
36、 direction parallel with the length of apertures. Beans remaining in apertures shall be considered to be retained on the sieve in question.7.3.2.2 Remove all the beans from each sieve separately, to avoid loss of the beans. Put the lid on the top of the respective sieve, then put one hand under the
37、sieve and push the beans up. Then, carefully place the beans on a tray.7.3.2.3 Weigh to the nearest 0,1 g, the beans collected on each of the sieves used and in the receiver.7.4 Additional observationsNote whether any of the fractions contains a significant proportion of foreign matter, bean fragmen
38、ts or broken beans. In this case, apply ISO 4149.ISO 4150:2011(E) ISO 2011 All rights reserved 3BS ISO 4150:20118 Statement of results8.1 The result, wgc, is expressed as a mass fraction retained over each sieve in the following manner:wmmgcST= 100wherewgcis the mass fraction retained with the sieve
39、 number, S;mSis the coffee bean mass, with the sieve number, S, expressed in grams; mTis the total mass of the sample, expressed in grams.8.2 The total percentage of all sieves shall be equal to (100 0,5) % of the mass of the test portion. If this is not the case, the test is not valid and shall be
40、repeated using another laboratory sample.9 Precision9.1 GeneralThe results of an interlaboratory test are given in Annex C. 9.2 RepeatabilityThe absolute difference between two single test re sults for a given sieve size, S, obtained using the same method on the identical test material in the same l
41、aboratory by the same operator using the same equipment within a short interval of time, should not be greater than the repeatability limit, rS, for this sieve.rS= 2,8 Sr= 0,0187 wS+ 0,099 1where wSis the mean of the results on the respective sieve.9.3 ReproducibilityThe absolute difference between
42、two single test re sults for a given sieve size, S, obtained using differ ent equipment, should not be greater than the re producibility limit, RS, for this sieve.RS = 2,8 SR= 0,1237 wS+ 0,590 9where wSis the mean of the results on the respective sieve.10 Test reportThe test report shall contain at
43、least the following information: a) reference to this International Standard, i.e. ISO 4150:2011;b) all the information necessary for the complete identification of the sample; c) specification of the method and type of sieve used; d) the test result(s) obtained;e) the details of any foreign matter
44、or defect found and recorded in accordance with 7.4; ISO 4150:2011(E)4 ISO 2011 All rights reservedBS ISO 4150:2011f) all operating details not specified in this International Standard or regarded as optional, together with any incidents which can have influenced the result(s).ISO 4150:2011(E) ISO 2
45、011 All rights reserved 5BS ISO 4150:2011Annex A (normative) Characteristics of perforated metal plate test sieves with round holesThe sequence of aperture diameters is taken from the R 40 series of preferred numbers in ISO 3.The sieves numbers 7, 10, 12, 121/2, 14, 15, 16, 17, 18, 19 and 20 shall c
46、omply with the requirements of ISO 3310-2, except that the tolerance on the normal diameter shall be as shown in Table A.1.The technical specifications of sieves numbers 15 and 19 shall be obtained by interpolation from those given in ISO 3310-2, except that the tolerance on the normal diameter shal
47、l be as shown in Table A.1.The arrangement of the apertures shall be such that the aperture centres are at the apices of equilateral triangles (see Figure A.1).Table A.1 Characteristics of perforated metal plate test sieves with round holesAperture sizemmSieve numberNominal diameterwTolerance8,007,5
48、07,106,706,306,005,605,004,754,002,80 0,09 0,09 0,09 0,08 0,08 0,08 0,07 0,07 0,07 0,06 0,052019181716151412 1/212107ISO 4150:2011(E)6 ISO 2011 All rights reservedBS ISO 4150:2011Keyp pitchw hole size NOTE Values of the pitch, p, are given in ISO 3310-2.Figure A.1 Round holes Staggered arrangementIS
49、O 4150:2011(E) ISO 2011 All rights reserved 7BS ISO 4150:2011Annex B (normative) Characteristics of perforated metal plate test sieves with slotted aperturesThe sequence of slot widths is taken from the R 40 series of preferred numbers in ISO 3.The slots shall be arranged in rows (see Figure B.1) or staggered. The values given for the pitches should be regarded as a nominal guide.Table B.1 Characteristics of perforated metal plate test sieves with slotted aperturesAperture size mmPitch m