BS EN ISO 5809-1994 Starches and derived products - Determination of sulfated ash《淀粉及其制品 硫酸盐灰分测定》.pdf

1、BRITISH STANDARD BS EN ISO 5809:1994 Starches and derived products Determination of sulfated ash The European Standard EN ISO5809:1994 has the status of a BritishStandard UDC 664.2:543.822BSENISO5809:1994 This BritishStandard, having been prepared under the directionof the BSI Standards Board, was p

2、ublished under theauthority of the Standards Board and comes into effect on 15 December 1994 BSI 01-2000 The following BSI references relate to the work on this standard: Committee reference AFC/- Draft announced in BSI News October 1992 ISBN 0 580 22820 7 Cooperating organizations The European Comm

3、ittee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries: Austria Oesterreichisches Normungsinstitut Belgium Institut belge de normalisation Denmark Dansk Standard Finland Suomen Standardis

4、oimisliito, r.y. France Association franaise de normalisation Germany Deutsches Institut fr Normung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standards Authority of Ireland Italy Ente Nazionale Italiano di Unificazione Luxembour

5、g Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Sweden Standardiseringskommissionen i Sverige Switzerland Association suisse de nor

6、malisation UnitedKingdom BritishStandards Institution Amendments issued since publication Amd. No. Date CommentsBSENISO5809:1994 BSI 01-2000 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword 2 1 Scope and field of application 3 2 References 3 3 Definition 3 4

7、 Principle 3 5 Reagents 3 6 Apparatus 3 7 Procedure 3 8 Expression of results 4 9 Test report 5 Annex ZA (normative) Normative references to international publications with their relevant European publications 6BSENISO5809:1994 ii BSI 01-2000 National foreword This BritishStandard has been prepared

8、under the direction of the BSIStandards Board and is the English language version of EN ISO5809:1994 Starches and derived products Determination of sulfated ash published by the European Committee for Standardization (CEN). It was derived by CEN from ISO5809:1982. This BritishStandard has been produ

9、ced to fulfil BSIs obligation to publish all approved European Standards but, because of the absence of interest in the UK in the subject concerned, there has been no UK participation in the preparation of EN25809. Any queries relating to the EN should be directed to BSI. A British Standard does not

10、 purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside fr

11、ont cover, pagesi andii, theEN ISO title page, pages2 to6 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO58

12、09 September 1994 UDC 664.2:543.822 Descriptors: Starches, chemical analysis, determination of sulfated ash English version Starches and derived products Determination of sulfatedash Amidons, fcules et produits drivs Dtermination des cendres sulfates Strke und Strkederivate BestimmungderSulfatasche

13、This European Standard was approved by CEN on 1994-09-06. 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. Up-to-date lists and bibliographical referenc

14、es concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. 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

15、its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Swit

16、zerland and UnitedKingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1994 Copyright reserved to CEN member Ref. No. EN ISO5809:1994 EENISO5809:1994 BSI 01-2000 2 Foreword The text

17、of the International Standard ISO5809:1982, was prepared by ISO/TC93, Starch (including derivatives and by-products), was submitted to Formal Vote and was approved by CEN as EN ISO5809 on 1994-09-06 without any modification. This European Standard shall be given the status of a national standard, ei

18、ther by publication of an identical text or by endorsement, at the latest by March 1995, and conflicting national standards shall be withdrawn at the latest by March 1995. According to the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austri

19、a, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, UnitedKingdom.ENISO5809:1994 BSI 01-2000 3 1 Scope and field of application This International Standard specifies a method for the determination of s

20、ulphated ash in starches and derived products. 2 References ISO1666, Starch Determination of moisture content Oven-drying methods 1) . ISO1741, Dextrose Determination of loss in mass on drying Vacuum oven method. ISO1742, Glucose syrups Determination of dry matter Vacuum oven method. ISO1743, Glucos

21、e syrup Determination of dry matter Refractive index method. 3 Definition sulphated ash the residue obtained after incineration of the product, according to the method specified in this International Standard it is expressed as a percentage by mass either of the product as-received or on the dry bas

22、is 4 Principle Incineration of a test portion, in the presence of sulphuric acid, at a temperature of525 25 C. The sulphuric acid facilitates the destruction of the organic matter and avoids losses by converting the volatile chlorides into non-volatile sulphates. 5 Reagents During the analysis, use

23、only reagents of recognized analytical quality and only distilled water or water of at least equivalent purity. 5.1 Sulphuric acid solution Add, carefully,100ml of concentrated sulphuric acid, 20 1,83g/ml, to300ml of water and mix. 5.2 Hydrochloric acid solution Add, carefully,100ml of concentrated

24、hydrochloric acid, 20 1,19g/ml, to500ml of water and mix. 6 Apparatus Ordinary laboratory apparatus, and in particular 6.1 Incineration dish, of platinum or any other material which does not deteriorate under the test conditions (for example a silica incineration dish), of capacity100 to200ml and wi

25、th a minimum useful surface of15cm 2 . 6.2 Electric furnace with air circulation, capable of being controlled at525 25 C. 6.3 Electric hot-plate or gas burner or heating lamp. 6.4 Desiccator, provided with an efficient desiccant. 6.5 Water bath, capable of being controlled at60 to70 C. 6.6 Analytica

26、l balance 7 Procedure 7.1 Preparation of the incineration dish Clean the incineration dish(6.1), whether it is new or used, with boiling hydrochloric acid solution(5.2), then rinse generously with water. Calcinate the incineration dish for30min in the furnace(6.2), controlled at525 25 C. Allow to co

27、ol to ambient temperature in the desiccator(6.4) and weigh to the nearest0,0002g (the incineration dish should be calcinated to constant mass). 7.2 Preparation of the test sample Mix the sample carefully and quickly by stirring (fora powder) or by mixing with a spatula (for a liquid) in a sample con

28、tainer. 2) If the volume of the container is insufficient for this, quickly transfer the whole sample to another, previously dried container of a suitable size. Take care to avoid any change in the moisture content of the sample. The taking of a representative sample of approximately5g can be diffic

29、ult (for example glucose in lumps). In this case, use one of the procedures described below: a) Weigh carefully, to the nearest0,01g, approximately100g of the sample into a dry container, provided with a lid, previously tared with the lid. Add approximately100ml of water at90 C, place the lid on the

30、 container and stir until the sample is completely dissolved. Allow to cool to ambient temperature and weigh to the nearest0,01g. b) Melt the sample in solid form by immersing it, in a container, provided with a lid, in the water bath(6.5), controlled at60 to70 C, and placing the lid on the containe

31、r. Remove the container from the water bath and allow it to cool to ambient temperature, agitating frequently but without removing the lid, and then mix the condensed water with the sample. 1) Under revision. 2) For glucose syrup, remove the surface layer (approximately0,5cm) before mixing.ENISO5809

32、:1994 4 BSI 01-2000 7.3 Test portion If a dilution has been carried out, take an aliquot portion of the solution obtained (see7.2), so as to obtain a mass of sample corresponding to a mass of test portion as shown in the table. In all other cases, weigh, to the nearest0,001g, in the incineration dis

33、h(6.1), previously weighed to the nearest0,0002g, a mass of test sample(7.2) in accordance with the following table. 7.4 Preincineration Add5ml of the sulphuric acid solution(5.1) to the test portion or the aliquot portion(7.3). Mix with a glass stirring rod and rinse with a little water, collecting

34、 the rinsings in the incineration dish. Heat the incineration dish slowly and carefully, over the electric hot-plate or gas burner or using the heating lamp(6.3), until completely carbonized (it is recommended that this be carried out under an extraction hood). 7.5 Incineration Place the incineratio

35、n dish in the oven(6.2), controlled at525 25 C, and maintain this temperature until the carbon residue has disappeared. A period of2h is usually sufficient. Allow to cool. Take up the residue with several drops of the sulphuric acid solution(5.1), evaporate on the edge of the oven(6.2) and incinerat

36、e again for0,5h. Place the incineration dish in the desiccator(6.4) and allow it to cool to ambient temperature. Weigh the dish and contents to the nearest0,0002g. The incineration should be continued until constant mass is attained. Do not put more than four incineration dishes in the desiccator at

37、 any one time. 7.6 Number of determination Carry out two determinations on test portions taken from the same test sample(7.2). 8 Expression of results 8.1 Method of calculation and formulae The sulphated ash, expressed as a percentage by mass of product as-received, is given by the formula The sulph

38、ated ash, expressed as a percentage in mass on the dry basis, is given by the formula where m 0 is the mass, in grams, of the test portion, taking into account any dilution(7.3); m 1 is the mass, in grams, of the incineration dish before incineration(7.1); m 2 is the mass, in grams, of the incinerat

39、ion residue and incineration dish after incineration(7.5); H is the moisture content of the product, determined concurrently in accordance with ISO1666, ISO1741, ISO1742 or ISO1743. Take as the result the arithmetic mean of the values obtained in the two determinations, provided that the conditions

40、of repeatability (see8.2) are satisfied. If not, repeat the test. NOTEIn the hydrolysis products of starch containing sodium chloride as the preponderant mineral matter, the ash may be evaluated as sodium chloride by conventionally multiplying the sulphated ash by the coefficient0,823 which is the r

41、atio Express the result rounded to two decimal places. 8.2 Repeatability The absolute difference between the values obtained in two determinations carried out simultaneously or in rapid succession by the same analyst on the same test sample shall not be greater than 4% of their arithmetic mean in th

42、e case of sulphated ash greater than2% (m/m); 0,08g per100g in the case of sulphated ash less than2% (m/m). Sulphated ash Mass of test portion % (m/m) g u 5 5u 10 10 10 5 2 m 2 m 1 () 100 m 0 - m 2 m 1 () 100 m 0 - 100 100H - sodium chloride sodium sulphate - 2 (NaCl) (Na 2 SO 4 ) - =ENISO5809:1994

43、BSI 01-2000 5 8.3 Reproducibility The absolute difference between the values obtained in two determinations carried out on the same sample in two different laboratories shall not exceed 0,1g per100g for sulphated ash less than0,5% (m/m); 1% of their arithmetic mean for sulphated ash greater than5% (

44、m/m); 20% of their arithmetic mean for sulphated ash between0,5 and5% (m/m). 9 Test report The test report shall indicate the method used, together with the result obtained and the method of expression used. It shall also mention any operating conditions not specified in this International Standard,

45、 or regarded as optional, as well as any circumstances that may have affected the results. The test report shall include all details required for the complete identification of the sample.ENISO5809:1994 6 BSI 01-2000 Annex ZA(normative) Normative references to international publications with their r

46、elevant European publications This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or

47、 revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). Publication Year Title EN Year ISO1666 1973 Starch Determination of

48、moisture content Oven-drying method EN ISO1666 1994 ISO1741 1980 Dextrose Determination of loss in mass on drying Vacuum oven method EN ISO1741 1994blankBS EN ISO 5809:1994 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for pr

49、eparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or revision. Users of BritishStandards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and services. We would be gr