DIN EN ISO 5530-2-2015 Wheat flour - Physical characteristics of doughs - Part 2 Determination of rheological properties using an extensograph (ISO 5530-2 2012) German version EN I.pdf

1、March 2015 Translation by DIN-Sprachendienst.English price group 12No 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!%AR:“2304723www.din.deDDIN EN ISO 5530-2Wheat flour Physical characteristics of doughs Part 2: Determination of rheological properties using an extensograph(ISO 5530-2:2012);English version EN ISO 5530-2:2014,English translation of DIN EN ISO 5530-2:2015-03Weizenmehl Physikalische Eigenschaft

3、en von Teigen Teil 2: Bestimmung der rheologischen Eigenschaften mittels Extensograph(ISO 5530-2:2012);Englische Fassung EN ISO 5530-2:2014,Englische bersetzung von DIN EN ISO 5530-2:2015-03Farines de bl tendre Caractristiques physiques des ptes Partie 2: Dtermination des caractristiques rhologiques

4、 au moyen de lextensographe(ISO 5530-2:2012);Version anglaise EN ISO 5530-2:2014,Traduction anglaise de DIN EN ISO 5530-2:2015-03www.beuth.deDocument comprises 19 pagesIn case of doubt, the German-language original shall be considered authoritative.03.15 DIN EN ISO 5530-2:2015-03 2 A comma is used a

5、s the decimal marker. National foreword This document (ISO 5530-2:2012) has been prepared by Technical Committee ISO/TC 34 “Food products” (Secretariat: AFNOR, France), Subcommittee SC 4 “Cereals and pulses” (Secretariat: SAC, China) and has been taken over as EN ISO 5530-2:2014 by Technical Committ

6、ee CEN/TC 338 “Cereal and cereal products” (Secretariat: AFNOR, France). The responsible German body involved in its preparation was the DIN-Normenausschuss Lebensmittel und landwirtschaftliche Produkte (DIN Standards Committee Food and Agricultural Products), Working Committee NA 057-05-06 AA Getre

7、ide und Getreideerzeugnisse. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 712 DIN EN ISO 712 ISO 5530-1 DIN EN ISO 5530-1 National Annex NA (informative) Bibliography DIN EN ISO 712, Cereals and cereal products Determination of moist

8、ure content Reference method DIN EN ISO 5530-1, Wheat flour Physical characteristics of doughs Part 1: Determination of water absorption and rheological properties using a farinograph EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 5530-2 December 2014 ICS 67.060 English Version Wheat flour

9、 - Physical characteristics of doughs - Part 2: Determination of rheological properties using an extensograph (ISO 5530-2:2012) Farines de bl tendre - Caractristiques physiques des ptes - Partie 2: Dtermination des caractristiques rhologiques au moyen de lextensographe(ISO 5530-2:2012) Weizenmehl -

10、Physikalische Eigenschaften von Teigen - Teil 2: Bestimmung der rheologischen Eigenschaften mittels Extensograph (ISO 5530-2:2012) 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

11、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 European Standard exists in th

12、ree 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 the national standards b

13、odies 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, Portugal, Romania, Slovakia, Slovenia,

14、 Spain, Sweden, Switzerland, 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 worl

15、dwide for CEN national Members. Ref. No. EN ISO 5530-2:2014 EContents PageForeword .31 Scope 42 Normative references . 43 Terms and definitions . 44 Principle . 55 Reagents 56 Apparatus 57 Sampling 68 Procedure 68.1 Determination of the moisture content of the flour 68.2 Preparation of apparatus . 6

16、8.3 Test portion . 78.4 Preparation of the dough 78.5 Determination . 89 Expression of results . 89.1 General . 89.2 Water absorption . 99.3 Resistance to stretching . 99.4 Extensibility, E 99.5 Energy 99.6 Ratio (R/E) 910 Precision 1010.1 Repeatability . 1010.2 Reproducibility . 1011 Test report .

17、11Annex A (informative) Description of the extensograph 12Annex B (informative) Results of interlaboratory tests 16Bibliography .17DIN EN ISO 5530-2:2015-03 EN ISO 5530-2:2014 (E) 2 Foreword The text of ISO 5530-2:2012 has been prepared by Technical Committee ISO/TC 34 “Food products” of the Interna

18、tional Organization for Standardization (ISO) and has been taken over as EN ISO 5530-2:2014 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 i

19、dentical text or by endorsement, at the latest by June 2015, and conflicting national 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 re

20、sponsible 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 European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Fi

21、nland, 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, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of

22、 ISO 5530-2:2012 has been approved by CEN as EN ISO 5530-2:2014 without any modification. DIN EN ISO 5530-2:2015-03 EN ISO 5530-2:2014 (E) 3 1 ScopeThis part of ISO 5530 specifies a method, using an extensograph, for the determination of the rheological properties of wheat flour dough in an extensio

23、n test. The recorded loadextension curve is used to assess general quality of flour and its response to improving agents.The method is applicable to experimental and commercial flours from wheat (Triticum aestivum L.).NOTE This part of ISO 5530 is based on ICC 114.32 Normative referencesThe followin

24、g 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 products Determination of moisture

25、 content Reference methodISO 5530-1:,1)Wheat flour Physical characteristics of doughs Part 1: Determination of water absorption and rheological properties using a farinograph3 Terms and definitionsFor the purposes of this part of ISO 5530, the following terms and definitions apply.3.1energycapacity

26、to do workNOTE 1 For the purposes of this part of ISO 5530, the energy is determined as the area under a recorded curve. The energy describes the work applied when stretching a dough sample.NOTE 2 The area is measured by a planimeter and reported in square centimetres.3.2extensibilityEdistance trave

27、lled by the recorder paper from the moment that the hook touches the test piece until rupture of (one of the strings of) the test pieceNOTE See 9.4 and Figure 1.3.3extensograph water absorptionvolume of water required to produce a dough with a consistency of 500 farinograph units (FU) after 5 min mi

28、xing, under specified operating conditionsNOTE Extensograph water absorption is expressed in millilitres per 100 g of flour at 14,0 % mass fraction moisture content.1) To be published. (Revision of ISO 5530-1:1997)DIN EN ISO 5530-2:2015-03 EN ISO 5530-2:2014 (E) 4 3.4maximum resistanceRmmean of the

29、maximum heights of the extensograph curves from the two test pieces, provided that the difference between them does not exceed 15 % of their mean valueNOTE See 9.3.1 and Figure 1.3.5ratio (R/E)quotient of the maximum resistance, Rm, and the extensibility or the resistance after 50 mm transposition o

30、f the recorder paper, R50, and the extensibility NOTE The ratio is an additional factor in the review of the dough behaviour.3.6resistance at constant deformationmean of the heights of the extensograph curves after 50 mm transposition of the recorder paper from the two test pieces, provided that the

31、 difference between them does not exceed 15 % of their mean valueNOTE See 9.3.2 and Figure 1.3.7stretching characteristicsresistance of dough to extension and the extent to which it can be stretched until breaking, under specified operating conditionsNOTE 1 The resistance is expressed in arbitrary u

32、nits (extensograph units, EU).NOTE 2 The extent of stretching is expressed in millimetres or centimetres.4 PrincipleDough is prepared from flour, water and salt in a farinograph under specified conditions. A test piece is then moulded on the balling unit and moulder of the extensograph into a standa

33、rd shape. After a fixed period of time, the test piece is stretched and the force required recorded. Immediately after these operations, the same test piece is subjected to two further cycles of moulding, rest period and stretching.The size and shape of the curves obtained are a guide to the physica

34、l properties of the dough. These physical properties influence the end-use quality of the flour.5 ReagentsUse only reagents of recognized analytical grade, unless otherwise specified, and distilled or demineralized water or water of equivalent purity.5.1 Sodium chloride.6 ApparatusUsual laboratory a

35、pparatus and, in particular, the following.6.1 Extensograph,2)with a thermostat consisting of a constant temperature water bath (see Annex A), with the following operating characteristics:2) This document has been drawn up on the basis of the Brabender Extensograph, which is an example of a suitable

36、 product available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of this product. Other equipment may be used if it can be shown to give comparable results.DIN EN ISO 5530-2:2015-03 EN ISO 5530-2:2014 (E) 5 rotatio

37、nal frequency of balling unit: (83 3) min1(r/min); rotational frequency of moulder: (15 1) min1(r/min); hook speed: (1,45 0,05) cm/s; chart speed: (0,65 0,01) cm/s; force exerted per extensograph unit: (12,3 0,3) mN/EU (1,25 0,03) gf/EU.Some instruments have a different calibration for force/unit de

38、flection. The procedure specified can be used with such instruments, but it is necessary for the different calibration to be taken into account when comparing the results with instruments calibrated as above.NOTE An electronic extensograph can be used, see A.5.6.2 Farinograph,3)connected to a simila

39、r thermostat as the extensograph, with the operating characteristics specified in ISO 5530-1, and a burette as specified in ISO 5530-1.6.3 Balance, capable of being read to the nearest 0,1 g.6.4 Spatula, made of soft plastic.6.5 Conical flask, of 250 ml capacity.7 SamplingSampling is not part of the

40、 method specified in this International Standard. A recommended sampling method is given in ISO 24333.2It is important that the laboratory receive a truly representative sample which has not been damaged or changed during transport and storage.8 Procedure8.1 Determination of the moisture content of

41、the flourDetermine the moisture content of the flour using the method specified in ISO 712.8.2 Preparation of apparatus8.2.1 Turn on the thermostat of the farinograph (6.2) and circulate the water until the required temperatures are reached, prior to using the instrument. Before and during use, chec

42、k the temperatures of the thermostats; the mixing bowl of the farinograph, in the hole provided for this purpose; and the extensograph cabinet.All temperatures shall be (30 0,2) C.8.2.2 Adjust the arm of the pen of the extensograph so as to obtain zero reading when a cradle with both its clamps plus

43、 a 150 g mass (“weight”) is placed in position.3) The Farinograph is the trade name of a product supplied by Brabender. This information is given for the 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

44、can be shown to lead to the same results.DIN EN ISO 5530-2:2015-03 EN ISO 5530-2:2014 (E) 6 8.2.3 Pour some water into the trough of each cradle support, and place the supports, cradles, and clamps in the cabinet at least 15 min before use.8.2.4 Uncouple the mixer of the farinograph from the driving

45、 shaft and adjust the position of the counterweight(s) so as to obtain zero deflection of the pointer with the motor running at the specified rotational frequency (see ISO 5530-1:, 6.1). Switch off the motor and then couple the mixer.Lubricate the mixer with a drop of water between the back-plate an

46、d each of the blades. Check that the deflection of the pointer is within the range (0 5) FU with the mixing blades operating at the specified rotational frequency in the empty, clean bowl. If the deflection exceeds 5 FU, clean the mixer more thoroughly or eliminate other causes of friction.Adjust th

47、e arm of the pen so as to obtain identical readings from the pointer and the recording pen.Adjust the damper so that, with the motor running, the time required for the pointer to go from 1 000 FU to 100 FU is (1,0 0,2) s.8.2.5 Fill the burette of the farinograph, including the tip, with water at a temperature of (30 0,5) C.8.3 Test portionIf necessary, bring the flour to a temperature o