EN ISO 12873:2014

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Olivenöle und Oliventresteröle - Bestimmung des Wachsgehaltes in Olivenölen mittels Kapillarsäulen-Gaschromatographie (ISO 12873:2010)Huiles d'olive et huiles de grignons d'olive - Détermination de la teneur en cires par chromatographie en phase gazeuse sur colonne capillaire (ISO 12873:2010)Olive oils and olive-pomace oils - Determination of wax content by capillary gas chromatography (ISO 12873:2010)67.200.10Animal and vegetable fats and oilsICS:Ta slovenski standard je istoveten z:EN ISO 12873:2014SIST EN ISO 12873:2014en01-september-2014SIST EN ISO 12873:2014SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN ISO 12873
April 2014 ICS 67.200.10 English Version
Olive oils and olive-pomace oils - Determination of wax content by capillary gas chromatography (ISO 12873:2010)
Huiles d'olive et huiles de grignons d'olive - Détermination de la teneur en cires par chromatographie en phase gazeuse sur colonne capillaire (ISO 12873:2010)
Olivenöle und Oliventresteröle - Bestimmung des Wachsgehaltes in Olivenölen mittels Kapillarsäulen-Gaschromatographie (ISO 12873:2010) This European Standard was approved by CEN on 11 April 2014.
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 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 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 CEN-CENELEC Management Centre has the same status as the official versions.
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Reference numberISO 12873:2010(E)© ISO 2010
INTERNATIONAL STANDARD ISO12873First edition2010-05-01Olive oils and olive-pomace oils — Determination of wax content by capillary gas chromatography Huiles d'olive et huiles de grignons d'olive — Détermination de la teneur en cires par chromatographie en phase gazeuse sur colonne capillaire
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ISO 12873:2010(E) © ISO 2010 – All rights reserved iii 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 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, also 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 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 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 document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 12873 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 11, Animal and vegetable fats and oils. SIST EN ISO 12873:2014

ISO 12873:2010(E) iv © ISO 2010 – All rights reserved Introduction As part of the Trade standard applying to olive oils and olive-pomace oils, the International Olive Oil Council (IOOC) — now known as International Olive Council (IOC) — published COI/T.20/Doc. 18:2007[4]. COI/T.20/Doc. 18 was applicable to olive and olive-pomace oils and was used to distinguish between oils obtained by either pressing or centrifuging and olive-pomace oils. Olive pomace is the residual paste which still contains a variable amount of water and oil after pressing or centrifuging. In 2008, the IOC submitted the document to ISO/TC 34/SC 11 for adoption as an International Standard.
INTERNATIONAL STANDARD ISO 12873:2010(E) © ISO 2010 – All rights reserved 1 Olive oils and olive-pomace oils — Determination of wax content by capillary gas chromatography 1 Scope This International Standard specifies the determination of the wax content, as a mass fraction expressed in milligrams per kilogram, of olive oils and olive-pomace oils. The individual waxes are separated according to the number of carbon atoms. The method is recommended for distinguishing between olive oil obtained by pressing or centrifuging and that obtained from olive pomace (olive-pomace oil). NOTE This International Standard is based on COI/T.20/Doc. 18/Rev. 2:2007[4]. 2 Normative references The following 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 661, Animal and vegetable fats and oils — Preparation of test sample 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 wax content mass fraction of those substances in a sample determined in accordance with the method specified in this International Standard NOTE The wax content is expressed in milligrams per kilogram. 4 Principle After a suitable internal standard has been added, the oil is fractionated by chromatography on a hydrated silica gel column. The fraction eluted under test conditions (which has a lower polarity than the triglycerides) is recovered and analysed by capillary gas chromatography. 5 Reagents WARNING — Comply with any local regulations which specify the handling of hazardous substances. Technical, organizational and personal safety measures shall be followed. During the analysis, unless otherwise stated, use only reagents of recognized analytical grade, and distilled or demineralized water or water of equivalent purity. SIST EN ISO 12873:2014

ISO 12873:2010(E) 2 © ISO 2010 – All rights reserved 5.1 Silica gel, with a particle size of 60 µm to 200 µm, prepared as follows: place the gel in the muffle oven at 500 °C for at least 4 h; allow to cool, then add 2 % of water in relation to the mass of silica gel used; shake well to homogenize the slurry. Store in darkness for at least 12 h prior to use. 5.2 n-Hexane, chromatography grade. 5.3 Diethyl ether, chromatography grade. 5.4 n-Heptane, chromatography grade. 5.5 Internal standard, solution of lauryl arachidate in hexane, mass concentration 0,1 g/100 ml. NOTE Palmityl palmitate or myristyl stearate may also be used. 5.6 Sudan I (1-phenylazo-2-naphthol). 5.7 Carrier gas: hydrogen or helium, gas chromatography grade. 5.8 Auxiliary gases: hydrogen, free from moisture and organic substances, and synthetic air, gas chromatography grade. 6 Apparatus Usual laboratory apparatus and, in particular, the following. 6.1 Erlenmeyer flask, 25 ml. 6.2 Glass column for liquid chromatography, of diameter 15,0 mm and length 30 cm to 40 cm, with stopcock. 6.3 Gas chromatograph, suitable for use with a capillary column, equipped with the components specified in 6.3.1 to 6.3.5. 6.3.1 Cold on-column injector. 6.3.2 Thermostat-controlled oven with temperature programming. 6.3.3 Flame-ionization detector. 6.3.4 Computer-based integration system. 6.3.5 Capillary column, fused silica, of length 8 m to 12 m and internal diameter 0,25 mm to 0,32 mm, with SE-52 or SE-541) liquid phase or equivalent, with a film thickness of 0,10 µm to 0,30 µm. 6.4 Microsyringe for on-column injection, of capacity 10 µl, with a hardened needle. 6.5 Electric shaker. 6.6 Rotary evaporator. 6.7 Muffle oven. 6.8 Analytical balance, for weighing to an accuracy of 0,1 mg.
1) SE-52 and SE-54 are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. SIST EN ISO 12873:2014

ISO 12873:2010(E) © ISO 2010 – All rights reserved 3 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 that the laboratory receive a truly representative sample which has not been damaged or changed during transport or storage. 8 Preparation of the test sample Prepare the test sample in accordance with ISO 661. 9 Procedure 9.1 Preparation of the chromatography column Suspend 15 g of silica gel (5.1) in n-hexane (5.2) and introduce into the chromatography column (6.2). Allow to settle spontaneously. Use an electric shaker (6.5) to assist in complete settling to make the chromatographic band more homogeneous. Percolate 30 ml n-hexane to remove any impurities. Weigh, to the nearest 0,1 mg, about 500 mg of the sample into a 25 ml Erlenmeyer flask (6.1), add a suitable amount of internal standard (5.5) depending on the assumed wax content. Add 0,1 mg of lauryl arachidate in the internal standard solution (5.5) in the case of olive oil, and 0,25 mg to 0,50 mg in the case of olive-pomace oil. Transfer the test portion to the chromatographic column with the aid of two 2 ml portions of n-hexane. Allow the solvent to drain off to 1 mm above the upper level of the absorbent. Percolate a further 70 ml of
n-hexane to remove any n-alkanes naturally present. Then start chromatographic elution by collecting 180 ml of a mixture of 99 ml/100 ml n-hexane (5.2) and 1 ml/100 ml diethyl ether (5.3) at a rate of about 15 drops every 10 s. Perform the column chromatography at room temperature. Prepare the n-hexane-diethyl ether mixture freshly every day. To check visually that the waxes have been completely eluted, add 100 µl of Sudan I dye (5.6) solution at a concentration of 1 g/100 ml to the test portion solution. The dye is retained on the chromatographic column between the waxes and triglycerides. Hence, when the dye reaches the bottom of the column, suspend elution because all the waxes have been eluted. Evaporate the resultant fraction in a rotary evaporator (6.6) until the solvent is almost removed. Remove the last 2 ml of solvent under a weak stream of nitrogen, then add 2 ml to 4 ml of n-heptane. 9.2 Gas chromatographic analysis 9.2.1 Preliminary procedure If the column is being used for the first time, it is advisable to condition it. Run a light flow of gas through the column, then switch on the gas chromatograph. Heat gradually for approximately 4 h until a temperature of
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