EN 16620:2015

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Lebensmittelanalytik - Bestimmung von Furan in Kaffee und Kaffee-Erzeugnissen mit Headspace-Gaschromatographie und Massenspektrometrie (HS GC-MS)Analyse des produits alimentaires - Dosage du furane dans le café et les produits à base de café par chromatographie en phase gazeuse avec espace de tête couplée à la spectrométrie de masse (ET-CPG-SM)Food analysis - Determination of furan in coffee and coffee products by headspace gas chromatography and mass spectrometry (HS GC-MS)67.140.20Kava in kavni nadomestkiCoffee and coffee substitutesICS:Ta slovenski standard je istoveten z:EN 16620:2015SIST EN 16620:2015en,fr,de01-julij-2015SIST EN 16620:2015SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 16620
April 2015 ICS 67.140.20
English Version
Food analysis - Determination of furan in coffee and coffee products by headspace gas chromatography and mass spectrometry (HS GC-MS)
Analyse des produits alimentaires - Dosage du furane dans le café et les produits à base de café par chromatographie en phase gazeuse avec espace de tête couplée à la spectrométrie de masse (ET-CPG-SM)
Lebensmittelanalytik - Bestimmung von Furan in Kaffee und Kaffee-Erzeugnissen mit Headspace-Gaschromatographie und Massenspektrometrie (HS GC-MS) This European Standard was approved by CEN on 7 February 2015.
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.
CEN members are the national standards bodies 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, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
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Avenue Marnix 17,
B-1000 Brussels © 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16620:2015 E SIST EN 16620:2015

2 Contents Page Foreword .3 1 Scope .4 2 Normative references .4 3 Principle .4 4 Reagents .4 5 Apparatus .5 6 Procedure .6 7 Calculation .9 8 Precision . 10 9 Test report . 11 Annex A (informative)
Typical chromatograms . 12 Annex B (informative)
Precision data . 14 Bibliography . 15
4 1 Scope This European Standard specifies a method for the determination of furan in coffee and coffee products with headspace-gas chromatography-mass spectrometry (HS-GC-MS), see [1] and [2]. Coffee products in the scope of this method are extracts which have been spray-dried, agglomerated or freeze-dried. The method has been validated in an interlaboratory study via the analysis of naturally contaminated samples of spray-dried coffee, freeze-dried coffee and ground roasted coffee ranging from 264 µg/kg to 2 840 µg/kg. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO 3696:1995, Water for analytical laboratory use - Specification and test methods (ISO 3696:1987) 3 Principle Coffee and coffee products are weighed into headspace vials, diluted with water and incubated at 50 °C for 30 min. The furan content in the headspace is measured with HS-GC-MS. Quantification is done by using a standard addition curve, taking into account deuterated furan (d4-furan) as internal standard. 4 Reagents Use only reagents of recognized analytical grade and water complying with grade 1 of EN ISO 3696:1995, unless otherwise specified. Solvents shall be of quality for HPLC analysis. 4.1 Furan, (CAS 110-00-9), mass concentration
= 0,936 g/ml. 4.2 d4-Furan, (CAS 6142-90-1),
= 0,991 g/ml. 4.3 Methanol. 4.4 Potassium hydroxide, aqueous solution,
= 250 g/l. 4.5 Stock solutions 4.5.1 Furan stock solution,
approximately 2,50 mg/ml. Place 20 ml of methanol in a headspace vial and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 50 µl of furan through the septum of the vial into the methanol. Reweigh the sealed vial. Mix the contents well. The solution is stable for 2 weeks at 4 °C. Pierced headspace vials shall be re-capped. 4.5.2 d4-Furan stock solution,
approximately 2,50 mg/ml. Place 20 ml of methanol in a headspace vial and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 50 µl of d4-furan through the septum of the vial into the methanol. Reweigh the sealed vial. Mix the contents well. The solution is stable for 2 weeks at 4 °C. Pierced headspace vials shall be re-capped. SIST EN 16620:2015

approximately 25 µg/ml. Place 10 ml of water in a headspace vial and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 100 µl of furan stock solution (4.5.1) through the septum of the vial into the water. Reweigh the sealed vial. Mix the contents well. Prepare the solution daily. 4.6.3 d4-Furan standard solution 1,
approximately 25 µg/ml. Place 10 ml water in a headspace vial and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 100 µl of d4-furan stock solution (4.5.2) through the septum of the vial into the water. Reweigh the sealed vial. Mix the contents well. Prepare the solution daily. 4.6.4 Furan standard solution 2,
approximately 250 ng/ml. Place 10 ml water in a headspace vial and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 100 µl of furan standard solution 1 (4.6.2) through the septum of the vial into the water. Reweigh the sealed vial. Mix the contents well. Prepare the solution daily. 4.6.5 d4-Furan standard solution 2,
approximately 250 ng/ml. Place 10 ml water in a headspace vial and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 100 µl of d4-furan standard solution 1 (4.6.3) through the septum of the vial into the water. Reweigh the sealed vial. Mix the contents well. Prepare the solution daily. 5 Apparatus Usual laboratory glassware and equipment and, in particular, the following: 5.1 Positive displacement pipette. 5.2 Microlitre syringes. 5.3 Hand crimper and de-crimper. 5.4 Homogenizer or mill. 5.5 Test tube shaker. 5.6 Gas chromatograph for capillary gas chromatography, with split/splitless injector and headspace autosampler. SIST EN 16620:2015

6 5.6.1 Fused silica capillary column, suitable for analysing volatile organic compounds e.g. non-polar polysiloxane with 5 % phenyl. The following column has been shown to be suitable: J&W DB-5 from Agilent1) length of 60 m, internal diameter (i.d.) of 0,32 mm and film thickness (df) of 1 µm. 5.6.2 PLOT column for separation of very volatile compounds, e.g. HP® Plot Q from Agilent1), length of 15 m, i.d. of 0,32 mm and df of 20 µm coupled to a restriction column HP-5MS from Agilent1), length of 30 m, i.d. of 0,25 mm and df of 0,25 µm. This column is an alternative for the column given under 5.6.1. 5.6.3 Rt®Q-Bond.2) 5.6.4 Carrier gas, helium. 5.6.5 Mass spectrometer with capability of single ion monitoring, coupled to gas chromatograph. 5.7 Headspace vials, 20 ml, with aluminium crimp seals and PTFE-faced silicone septa. 6 Procedure 6.1 Sample preparation The samples shall be stored refrigerated in unopened original packages. Immediately prior to analysis the original packages should be opened and weighed with minimal delay to avoid losses of furan. Powdered samples should be weighed without further treatment. Coffee beans should be milled under conditions that do not raise the temperature and weighed. Although not tested in the interlaboratory study, the use of cooled milling equipment is recommended for milling in order to avoid losses of furan. Milling tests minimizing losses of furan should be performed ahead of the sample preparation. 6.2 Estimation of furan content The furan content in a sample is quantified by means of standard addition. The amount of furan and/or d4-furan which is added to the test portions is based on a rough estimation (x0) in relation to the initial sample weight. This rough estimation (x0) is done as follows: to 0,5 g to 5 g of the sample (normally 1 g) water is added (normally 5 ml), an amount of d4-furan (internal standard) in ng is added (approximately corresponding to the expected amount of furan in the sample) and is analysed with HS-GC-MS as described in 6.4. Using the peak area ratio furan/d4-furan (m/z = 68/72, see 7.2) and the amount of added internal standard in ng the furan content in relation to the initial weight of the sample solution can be estimated (equivalent to a simple isotope dilution analysis). In order to avoid the forming of furan from precursors, the pH value is adjusted to ca. pH = 10. For this 5 drops to 6 drops of potassium hydroxide solution (4.4) are added into the headspace vial.
1) These are examples of suitable products available commercially. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of these products. 2) Rt®-Q-Bond is an example of a suitable product available commercially. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of this product. SIST EN 16620:2015
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