1、BRITISH STANDARD BS EN ISO 3596:2001 BS 684-2.7:2001 Incorporating Corrigendum No. 1 Animal and vegetable fats and oils Determination of unsaponifiable matter Method using diethyl ether extraction The European Standard EN ISO 3596:2000 has the status of a British Standard ICS 67.200.10 NO COPYING WI
2、THOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS EN ISO 3596:2001 This British Standard, having been prepared under the direction of the Consumer products and Services Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 October 2001 B
3、SI 23 January 2002 ISBN 0 580 38045 9 National foreword This British Standard is the official English language version of EN ISO 3596:2001. It is identical with ISO 3596:2000. It supersedes BS EN ISO 3596-1:2000 which is withdrawn. The UK participation in its preparation was entrusted to Technical C
4、ommittee AW/11, Animal and vegetable fats and oils, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this do
5、cument may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of
6、 British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or pr
7、oposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page, the EN ISO foreword page, the ISO title page, pages ii
8、and iii, a blank page, pages 1 to 8, the Annex ZA page and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments 13636 Incorporating Corrigendum No. 1 23 January 2002 Replaced the EN ISO
9、 foreword page and inserted the Annex ZA page.EUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM ENISO3596 August2001 ICS67.200.10 SupersedesENISO35961:2000 Englishversion AnimalandvegetablefatsandoilsDeterminationof unsaponifiablematterMethodusingdiethyletherextraction (ISO3596:2000) Corpsgrasdorigines
10、animaleetvgtaleDtermination delateneurenmatiresinsaponifiablesMthodepar extractionloxydedithylique(ISO3596:2000) TierischeundpflanzlicheFetteundleBestimmungder unverseifbarenBestandteileVerfahrenmitDiethylether Extraktion(ISO3596:2000) ThisEuropeanStandardwasapprovedbyCENon25June2001. CENmembersareb
11、oundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisE
12、uropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,Czech
13、Republic,Denmark,Finland,France,Germany,Greece, Iceland,Ireland,Italy,Luxembourg,Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2001CEN Al
14、lrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.ENISO3596:2001ECORRECTED20011205 Foreword ThetextoftheInternationalStandardfromTechnicalCommitteeISO/TC34“Agriculturalfood products“oftheInternationalOrganizationforStandardization(ISO)hasbeentakenoverasan Eur
15、opeanStandardbyTechnicalCommitteeCEN/TC307“Oilseeds,vegetableandanimalfats andoilsandtheirbyproductsMethodsofsamplingandanalysis“,thesecretariatofwhichis heldbyAFNOR. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationof anidenticaltextorbyendorsement,atthelatestbyFebrua
16、ry2002,andconflictingnational standardsshallbewithdrawnatthelatestbyFebruary2002. ThisEuropeanStandardreplacesENISO35961:2000. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsof thefollowingcountriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,Czech Republic,
17、Denmark,Finland,France,Germany,Greece,Iceland,Ireland,Italy,Luxembourg, Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandtheUnitedKingdom. Endorsementnotice ThetextoftheInternationalStandardISO3596:2000hasbeenapprovedbyCENasa EuropeanStandardwithoutanymodification. NOTE:NormativereferencestoIn
18、ternationalStandardsarelistedinannexZA(normative). ENISO3596:2001 ISO 3596:2000(E) INTERNATIONAL STANDARD ISO 3596 First edition 2000-07-01 Animal and vegetable fats and oils Determination of unsaponifiable matter Method using diethyl ether extraction Corps gras dorigines animale et vgtale Dterminat
19、ion de la teneur en matires insaponifiables Mthode par extraction loxyde dithylique ENISO3596:2001 ii ENISO3596:2001 iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International S
20、tandards 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 represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, als
21、o take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. Draft International Standards adopt
22、ed by the technical committees are circulated to the member bodies for voting. Publication as an International Standard 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 International Standard may be the su
23、bject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. International Standard ISO 3596 was prepared by Technical Committee ISO/TC 34, Agricultural food products, Subcommittee SC 11, Animal and vegetable fats and oils. This first edition of ISO 3596 c
24、ancels and replaces ISO 3596-1:1988 and its Amendment 1:1997, of which it constitutes a minor revision. Annex A of this International Standard is for information only. ENISO3596:2001 ENISO3596:2001 INTENRATIONAL TSANDADR ISO 6953:(0002)E1 Animal and vegetable fats and oils Determination of unsaponif
25、iable matter Method using diethyl ether extraction 1 Scope This International Standard specifies a method using diethyl ether extraction for the determination of the unsaponifiable matter content of animal and vegetable fats and oils. This method is not applicable to waxes and, moreover, gives appro
26、ximate results with certain fats of high unsaponifiable matter content, for example with fats derived from marine animals. A method given in ISO 18609 may be used when climatic conditions, or regulations, do not permit the use of diethyl ether. 2 Normative reference The following normative document
27、contains provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged
28、 to investigate the possibility of applying the most recent edition of the normative document indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 661, Anim
29、al and vegetable fats and oils Preparation of test sample. 3 Term and definition For the purposes of this International Standard, the following term and definition applies. 3.1 unsaponifiable matter all the substances present in the product which, after saponification of the latter by potassium hydr
30、oxide and extraction by a specified solvent, are not volatile under the specified operating conditions 4P r i n c i p l e The fat or oil is saponified by boiling under reflux with an ethanolic potassium hydroxide solution. The unsaponifiable matter is extracted from the soap solution by diethyl ethe
31、r. The solvent is evaporated and the residue is weighed after drying. 5 Reagents Use only reagents of recognized analytical grade and distilled or deionized water or water of equivalent purity. 5.1 Diethyl ether, freshly distilled, free from peroxides and residue. ENISO3596:2001 2 5.2 Acetone. 5.3 P
32、otassium hydroxide, ethanolic solution, c(KOH) 1mol/l . Dissolve 60 g of potassium hydroxide in 50 ml of water and dilute to 1 000 ml with 95 % (by volume) ethanol. The solution should be colourless or straw-yellow. 5.4 Potassium hydroxide, aqueous solution, c(KOH) 0,5 mol/l. 5.5 Phenolphthalein, 10
33、 g/l solution in 95 % (by volume) ethanol. 6 Apparatus Usual laboratory apparatus and, in particular, the following. 6.1 Round-bottomed flasks, of 250 ml capacity, with ground neck. 6.2 Reflux condenser, with ground joint to fit the flasks (6.1). 6.3 Separating funnels, of 500 ml capacity, with stop
34、cock and stopper made of polytetrafluoroethylene. 6.4 Boiling water bath. 6.5 Oven, capable of being maintained at 103 C 2 C. 7 Sampling Sampling is not part of the method specified in this International Standard. A recommended sampling method is given in ISO 5555 1. It is important the laboratory r
35、eceive a sample which is truly representative and has not been damaged or changed during transport or storage. 8 Preparation of test sample Prepare the test sample in accordance with ISO 661. 9 Procedure 9.1 Test portion Weigh, to the nearest 0,01 g, about 5 g of the test sample (clause 8) into a 25
36、0 ml flask (6.1). 9.2 Saponification Add 50 ml of the potassium hydroxide solution (5.3) and a few anti-bumping granules. Attach the reflux condenser (6.2) to the flask and boil the contents gently for 1 h. Stop heating. Add 100 ml of water through the top of the condenser and swirl. If the extracti
37、on of the unsaponifiable matter is carried out with a view to the determination of the composition of tocopherols, the addition of pyrogallol is necessary and the extraction should be completed quickly (say, within 30 min). ENISO3596:2001 3 9.3 Extraction of unsaponifiable matter After cooling, tran
38、sfer the solution to a 500 ml separating funnel (6.3). Rinse the flask and the anti-bumping granules several times with the diethyl ether (5.1), using 100 ml in all, and pour these rinsings into the separating funnel. Stopper and shake vigorously for 1 min, periodically releasing pressure by inverti
39、ng the separating funnel and cautiously opening the stopcock. Allow to stand until there is complete separation of the two phases. Then run off the lower layer as completely as possible into a second separating funnel. If an emulsion is formed, destroy it by adding small quantities of ethanol or con
40、centrated potassium hydroxide or sodium chloride solution. Extract the aqueous ethanolic soap solution twice more, each time in the same way with 100 ml of the diethyl ether. Collect the three ether extracts in one separating funnel containing 40 ml of water. 9.4 Washing of ethereal extract Gently r
41、otate the separating funnel containing the combined extracts and the 40 ml of water. CAUTION Violent shaking at this stage may result in emulsions. Allow the layers to separate completely and draw off the lower aqueous layer. Wash the ethereal solution twice more with 40 ml portions of water, shakin
42、g vigorously each time and discarding the lower aqueous layer after separation. Draw off each washing solution leaving 2 ml, then rotate the separating funnel around its axis. Wait some minutes to allow the remaining aqueous layer to collect. Draw this off, closing the stopcock when the ethereal sol
43、ution reaches the bore of the stopcock. Wash the ethereal solution successively with 40 ml of the potassium hydroxide solution (5.4), 40 ml of water, and again with 40 ml of potassium hydroxide solution, then at least twice more with 40 ml of water. Continue to wash with water until the washings no
44、longer give a pink colour on the addition of a drop of the phenolphthalein solution (5.5). 9.5 Evaporation of solvent Transfer the ethereal solution quantitatively, a little at a time, through the top of the separating funnel into a 250 ml flask (6.1), previously dried at 103 C in the oven (6.5), th
45、en cooled and weighed to the nearest 0,1 mg. Evaporate the solvent on a boiling water bath (6.4). Add 5 ml of acetone (5.2) and evaporate the volatile solvent completely in a gentle current of air, holding the flask obliquely while turning it in a boiling water bath. 9.6 Drying the residue and deter
46、mination 9.6.1 Dry the residue in the oven (6.5) at 103 C for 15 min, with the flask in an almost horizontal position. Allow to cool in a desiccator and weigh to the nearest 0,1 mg. Repeat the drying for successive 15 min periods until the loss of mass between two successive weighings is less than 1
47、,5 mg. If a constant mass is not obtained after three periods of drying, the unsaponifiable matter is probably contaminated and the determination shall be repeated. NOTE If available, a vacuum rotary evaporator may be used, particularly if the unsaponifiable matter is to be examined further. 9.6.2 I
48、f a correction for free fatty acids is considered necessary, after weighing the residue dissolve it in 4 ml of the diethyl ether (5.1) and then add 20 ml of ethanol previously neutralized to a faint pink colour in the presence of the phenolphthalein (5.4) as indicator. Titrate with standard volumetric ethanolic potassium hydroxide solution, ENISO3596:2001 4 c(KOH) = 0,1 mol/l, to the same final colou
