1、BRITISH STANDARD BS EN ISO 11215:1998 Incorporating Amendment No.1 Modified starch Determination of adipic acid content of acetylated di-starch adipates Gas-chromatographic method The European Standard EN ISO11215:1998 together with amendment no.1 hasthe status of a British Standard ICS 67.180.20BSE
2、NISO11215:1998 This British Standard, having been prepared under the directionof the Consumer Products and Services Sector Board, was published under theauthority of the StandardsBoard and comesintoeffect on 15 July1998 BSI 05-1999 ISBN 0 580 30045 5 National foreword This British Standard is the En
3、glish language version of EN ISO 11215:1998. It is identical with ISO 11215:1998 and Amendment1:1998. This British Standard has been produced 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 bee
4、n no UK participation in the preparation of EN11215. Any queries relating to the EN should be directed to BSI quoting the reference AW/100. Cross-references Attention is drawn to the fact that CEN and CENELEC standards normally include an annex which lists normative references to international publi
5、cations with their corresponding European publications. The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Fi
6、nd” facility of the BSI Standards Electronic Catalogue. A British Standard does not 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 lega
7、l obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi and ii, theEN ISO title page, page2, the ISO title page, page ii, pages1 to6, aninsideback cover and a back cover. This standard has been updated (see copyright date) and may have had amendments inco
8、rporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date Comments 10408 February1999 Indicated by a sideline in the marginBSENISO 11215:1998 BSI 05-1999 i Contents Page National foreword Inside front cover Foreword 2 Forewor
9、d ii Text of ISO 11215 1ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 11215 May 1998 ICS 67.180.20 Incorporates corrigendum October1998 Descriptors: See ISO document English version Modified starch Determination of adipic acid content of acetylated di-starch adipates Gas-chromatog
10、raphic method (ISO11215:1998) (Incorporates corrigendum October1998) Amidons et fcules modifis Dtermination de la teneur en acide adipique dans les adipates de diamidon actyles Mthode par chromatographie en phase gazeuse (ISO11215:1998) (Inclut le corrigendum octobre1998) Modifizierte Strke Bestimmu
11、ng des Gehalts an Adipinsure in acetylierten Di-Strke-Adipaten Gaschromatographisches Verfahren (ISO11215:1998) (Eingearbeitet corrigendum Oktober1998) This European Standard was approved by CEN on24 May1998 and corrigendum October1998. CEN members are bound to comply with the CEN/CENELEC Internal R
12、egulations 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 Central Secretariat or to any CEN member. Thi
13、s 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 Central Secretariat has the same status as the official versions. CEN members are th
14、e national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee
15、 fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1998 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members Ref. No. EN ISO11215:1998 EENISO11215:1998 BSI 05-1999 2 Foreword The text of the International Standard ISO11215:1998 has
16、 been prepared by Technical Committee ISO/TC93, Starch (including derivatives and by-products), in collaboration with CEN/CS. 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 November1998, and conf
17、licting national standards shall be withdrawn at the latest by November1998. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, CzechRepublic, Denmark, Finland, France, Ge
18、rmany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and theUnitedKingdom. NOTE FROM CEN/CS: The foreword is susceptible to be amended on receipt of the German language version. The confirmed or amended foreword, and when appropriate, the norm
19、ative Annex ZA for the references to international publications with their relevant European publications will be circulated with the German version. Endorsement notice The text of the International Standard ISO11215:1998 was approved by CEN as a European Standard without any modification. Foreword
20、to corrigendum The text of the International Standard ISO11215:1998 has been prepared by Technical Committee ISO/TC93, Starch (including derivatives and by-products), in collaboration with CEN/CS. This European Standard shall be given the status of a national standard, either by publication of an id
21、entical text or by endorsement, at the latest by November1998, and conflicting national standards shall be withdrawn at the latest by November1998. Endorsement notice The text of the International Standard ISO11215:1998 was approved by CEN as a European Standard without any modification. NOTENormati
22、ve references to International Standards are listed in Annex ZA (normative). According to CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxe
23、mbourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and theUnitedKingdom. Contents Page Foreword 2 1 Scope 1 2 Normative references 1 3 Principle 1 4 Reagents and materials 1 5 Apparatus 1 6 Sampling 1 7 Preparation of test sample 2 8 Procedure 2 9 Expression of results 3 10 Precision
24、3 11 Test report 3 Annex A (informative) Typical conditions for chromatography 4 Annex B (informative) Typical chromatogram 5 Annex C (informative) Results of an interlaboratory trial 6 Annex D (informative) Bibliography Inside back cover Annex ZA (normative) Normative references to international pu
25、blications with their relevant European publications Inside back cover Figure B.1 Typical chromatogram of an acetylated adipyl cross-linked corn starch sample 5 Table 1 Repeatability limit (r) and reproducibility limit (R) 3 Table C.1 Statistical results for total adipic acid content 6 Table C.2 Sta
26、tistical results for free adipic acid content 6ENISO 11215:1998 ii BSI 05-1999 Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through I
27、SO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates
28、closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at leas
29、t75% of the member bodies casting a vote. International Standard ISO11215 was prepared by Technical Committee ISO/TC93, Starch (including derivatives and by-products). Annex A to Annex C of this International Standard are for information only. Descriptors: Carbohydrates, starches, food starch, adipa
30、tes, chemical analysis, determination of content, organic acids, gas phase chromatography.ENISO11215:1998 BSI 05-1999 1 1 Scope This International Standard specifies a method for the gas chromatographic determination of total adipic content and free adipic acid content of acetylated di-starch adipat
31、es. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of the publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based
32、 on the International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 1666:1996, Starch Determination of moisture content Oven-dryin
33、g method. ISO 3696:1987, Water for analytical laboratory use Specification and test methods. 3 Principle The test portion is dispersed in moderately concentrated sodium hydroxide solution, to hydrolyse fully the adipate from the starch. After acidification, the free adipic acid is extracted with eth
34、yl acetate. The ethyl acetate is removed, and the dry residue is silylated. An aliquot portion of this solution is injected into a gas chromatograph equipped with a capillary column. Pimelic acid is used as internal standard. Free adipic acid is extracted by washing out the starch with water, acidif
35、ying the extract, and extracting the free acid with ethyl acetate. The determination is performed by silylation and gas chromatography as described above. 4 Reagents and materials Use only reagents of recognized analytical grade. 4.1 Water, complying with at least grade3 in accordance with ISO3696.
36、4.2 Waxy maize starch, commercial grade. NOTEWaxy maize starch is chosen as the base material, as it represents the bulk of starch adipate on the market. This may be substituted with another native starch, if appropriate. 4.3 Adipic acid solution, (C 6 H 10 O 4 )=50,0mg/l. 4.4 Pimelic acid solution,
37、 (C 7 H 12 O 4 )=50,0mg/l. 4.5 Sodium hydroxide solution, c(NaOH)=4mol/l. 4.6 Hydrochloric acid, concentrated, c(HCl)=12mol/l. 4.7 Ethyl acetate (C 4 H 8 O 2 ). 4.8 Nitrogen gas, purity99%. 4.9 Acetonitrile 4.10 Silylation reagent: bis(trimethylsilyl)trifluoroacetamide (BSTFA) which includes1% trime
38、thylchlorosilane (TMCS). 4.11 Helium gas, purity99,9999% (e.g.grade N60). 4.12 Hydrogen gas, purity99,99% (e.g.grade N400 or better). 4.13 Air, purity99,999% (e.g.grade S). 5 Apparatus Usual laboratory apparatus and, in particular, the following. 5.1 Glass reaction tubes,100mm 16mm, with screw caps
39、fitted with polytetrafluoroethylene (PTFE) covered rubber seals resistant to concentrated hydrochloric acid(4.6). 5.2 Pipettes, adjustable, of1,00ml and5,00ml capacity, accurate to0,01ml. NOTEThe pipettes should be tested to see if they comply to manufacturers tolerance. Calibration may be required.
40、 5.3 Rotary shaker. 5.4 Pasteur pipettes. 5.5 Heating device, capable of being maintained at(30 2)C. 5.6 Evaporation device, based on solvent removal with a stream of nitrogen (e.g.Pierce Reacti-Vap III) 1) . 5.7 Ultrasonic bath, power120W. 5.8 Gas chromatograph, accommodating capillary columns, fit
41、ted with a flame ionization detector, on-column injector, and a computer integrator. SeeAnnex A for typical conditions for chromatography. 5.9 Sieve,8004m. 5.10 Blade mill. 5.11 Laboratory centrifuge, capable of operating at a radial acceleration of1100 g n . 6 Sampling It is important that the labo
42、ratory receive a sample which is truly representative and has not been damaged or changed during transport or storage. Sampling is not part of the method specified in this International Standard. 1) Pierce Reacti-Vap III is an example of suitable apparatus available commercially. This information is
43、 given for the convenience of users of this International Standard and does not constitute an endorsement by ISO of this apparatus.ENISO 11215:1998 2 BSI 05-1999 7 Preparation of test sample Sieve the laboratory sample through the8004m sieve(5.9). If the material does not pass through the sieve, the
44、n grind the sample with a blade mill(5.10) until it passes completely through the8004m sieve. Homogenize the sample. 8 Procedure 8.1 Calibration for total adipic acid content 8.1.1 Weigh, to the nearest0,1mg, approximately50mg of waxy maize starch(4.2) into each of four glass reaction tubes(5.1). 8.
45、1.2 Into one tube, pipette(5.2)1,00ml of adipic acid solution(4.3) and into the others0,75ml,0,50ml and0,25ml, respectively, of adipic acid solution(4.3). 8.1.3 Adjust the volume in each tube to1,5ml with water(4.1) and add1,00ml of pimelic acid solution(4.4) to each tube. Each tube then contains504
46、g of pimelic acid, and50,04g,37,54g,25,04g and12,54g respectively of adipic acid. NOTEIt is possible that pimelic acid contains some adipic acid. If this is proven, a fifth tube should be prepared in a similar fashion but without addition of adipic acid solution(4.3). 8.1.4 Agitate the tubes manuall
47、y to disperse the starch fully. Add2,5ml of sodium hydroxide solution(4.5). 8.1.5 Seal the tubes well and place on the rotary shaker(5.3) for5 min. 8.1.6 Remove the tubes and, with cooling, add1,0ml of hydrochloric acid(4.6). Mix well. 8.1.7 Add5ml of ethyl acetate(4.7). Seal the tubes tightly and s
48、hake vigorously for1min. 8.1.8 Let the tubes stand until good phase separation is achieved. With a Pasteur pipette(5.4), transfer the supernatant layer (ethyl acetate) to a clean screw-top tube. Make sure that none of the aqueous layer is carried over with the organic layer. 8.1.9 Place the tubes in
49、 the heating device(5.5) set at30C, and evaporate the ethyl acetate completely under a stream of nitrogen(4.8) with the evaporation device(5.6). 8.1.10 Repeat steps8.1.7 to8.1.9 three times more, accumulating the dried residue in the same tube. 8.1.11 Dissolve the total residue in0,6ml of acetonitrile(4.9) and place the closed tubes in the ultrasonic bath(5.7) for2 min. 8.1.12 Add0,3ml of the silylation reagent(4.10). Close the tubes and homogenize in the ultrasonic bath for2 min. 8.1.13 Place the tubes in the heating device(5.5)
