1、BSI Standards PublicationBS EN 16620:2015Food analysis Determinationof furan in coffee and coffeeproducts by headspace gaschromatography and massspectrometry (HS GC-MS)BS EN 16620:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 16620:2015.The UK participati
2、on in its preparation was entrusted to TechnicalCommittee AW/275, Food analysis - Horizontal methods.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are resp
3、onsible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 80860 9ICS 67.140.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards
4、 Policy and Strategy Committee on 30 April 2015.Amendments issued since publicationDate Text affectedBS EN 16620:2015EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16620 April 2015 ICS 67.140.20 English Version Food analysis - Determination of furan in coffee and coffee products by headspace g
5、as chromatography and mass spectrometry (HS GC-MS) Analyse des produits alimentaires - Dosage du furane dans le caf et les produits base de caf par chromatographie en phase gazeuse avec espace de tte couple la spectromtrie de masse (ET-CPG-SM) Lebensmittelanalytik - Bestimmung von Furan in Kaffee un
6、d 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 stat
7、us 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, Ge
8、rman). 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, Croat
9、ia, 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 Un
10、ited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: 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. E
11、N 16620:2015 E BS EN 16620:2015EN 16620:2015 (E) 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 da
12、ta . 14 Bibliography . 15 BS EN 16620:2015EN 16620:2015 (E) 3 Foreword This document (EN 16620:2015) has been prepared by Technical Committee CEN/TC 275 “Food analysis - Horizontal methods”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national stand
13、ard, either by publication of an identical text or by endorsement, at the latest by October 2015 and conflicting national standards shall be withdrawn at the latest by October 2015. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.
14、CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. WARNING The use of this document can involve hazardous materials, operation
15、s and equipment. This document does not purport to address all the safety problems associated with its use. It is the responsibility of the user of this document to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. According to
16、the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
17、 Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 16620:2015EN 16620:2015 (E) 4 1 Scope This European Standard specifies a method for the determ
18、ination 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 vi
19、a the analysis of naturally contaminated samples of spray-dried coffee, freeze-dried coffee and ground roasted coffee ranging from 264 g/kg to 2 840 g/kg. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its ap
20、plication. 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 cof
21、fee 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 Reagent
22、s 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.
23、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 l of furan through the septum of the vial into th
24、e 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 ch
25、illed syringe, transfer 50 l 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. BS EN 16620:2015EN 16620:2015 (E) 5 4.6 Standard solutions 4.6.1 General T
26、he amount of added solutions is calculated by differential weighing considering the densities. The solutions and additional dilutions should be kept cooled when working. Adapt the concentration of standard and internal standard solutions to the expected values in the samples. If necessary, prepare a
27、dditional dilutions according to the working range. All furan and d4-furan solutions should be prepared in different rooms. Use separate syringes without plastic material. 4.6.2 Furan standard solution 1, approximately 25 g/ml. Place 10 ml of water in a headspace vial and seal the vial. Weigh the se
28、aled vial. Using a chilled syringe, transfer 100 l 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 g/ml. Place 10 ml water in a headspace vi
29、al and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 100 l 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.
30、 Place 10 ml water in a headspace vial and seal the vial. Weigh the sealed vial. Using a chilled syringe, transfer 100 l 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 stan
31、dard 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 l 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. Pre
32、pare 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 chromat
33、ography, with split/splitless injector and headspace autosampler. BS EN 16620:2015EN 16620:2015 (E) 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 ASis the pea
34、k area m/z = 72 d4-furan. 7.3 For the standard calibration graph, plot the resulting peak area ratios (Q, see 7.2) against the fortified furan amount in ng according to the standard addition series. Calibration graph Q = bx + a or rather baQx)( = (2) where x is the mass of furan in ng in the sample;
35、 a is the intercept of the calibration graph; BS EN 16620:2015EN 16620:2015 (E) 10 b is the slope of the calibration graph. NOTE Calculation is done automatically by any modern chromatography software (mode: calculation with internal standard). 7.4 Calculate the furan content of the sample, in g/kg,
36、 by determination of the point of intersection with the prolonged calibration graph and the axis of abscissae. Determine the furan content in the sample in g/kg mathematically using Formula (3): baQx)( = (3) with Q = 0 becomes x = -a/b | = x/W where is the amount of furan in the sample (ng/g = g/kg)
37、; x is the mass of furan in ng in the sample (see 7.3); W is the initial sample weight in g (see 6.1). Result is given with 3 significant digits. 8 Precision 8.1 General Details of the interlaboratory test of the precision of the method are summarized in Annex B. The values derived from the interlab
38、oratory test may not be applicable to analyte concentration ranges and/or matrices other than those given in Annex B. 8.2 Repeatability The absolute difference between two single test results found on identical test material by one operator using the same apparatus within the shortest feasible time
39、interval will exceed the repeatability limit r in not more than 5 % of the cases. The values for spray-dried coffee are: x = 264 g/kg r = 53,5 g/kg (naturally contaminated) The values for freeze-dried coffee are: x = 1 140 g/kg r = 238 g/kg (naturally contaminated) The values for roasted coffee are:
40、 x = 2 840 g/kg r = 678 g/kg (naturally contaminated) BS EN 16620:2015EN 16620:2015 (E) 11 8.3 Reproducibility The absolute difference between two single test results found on identical test material reported by two laboratories will exceed the reproducibility limit R in not more than 5 % of the cas
41、es. The values for spray-dried coffee are: x = 264 g/kg R = 142 g/kg (naturally contaminated) The values for freeze-dried coffee are: x = 1 140 g/kg R = 517 g/kg (naturally contaminated) The values for roasted coffee are: x = 2 840 g/kg R = 1 530 g/kg (naturally contaminated) 9 Test report The test
42、report shall contain the following data: a) all information necessary for the identification of the sample (type of sample, origin and designation of the sample); b) a reference to this European Standard; c) the date and type of sampling procedure (if known); d) the date of receipt; e) the date of t
43、est; f) the test results and the units in which they have been expressed; g) any operations not specified in the method or regarded as optional, which might have affected the results. BS EN 16620:2015EN 16620:2015 (E) 12 Annex A (informative) Typical chromatograms a) Furan b) d4-Furan BS EN 16620:20
44、15EN 16620:2015 (E) 13 Key t time Y Abundance 1 m/z = 68 2 m/z = 39 3 m/z = 72 4 m/z = 42 Operating conditions capillary column RtQ-Bond3)(30 m, 0,32 mm, 10 m film thickness) Temperature programme 50 C (0,1 min), 10 C/min to 190 C (0 min), 40 C/min to 225 C (20 min). Flow 2,0 ml/min Figure A.1 Typic
45、al chromatogram of furan and d4-furan 3) 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. BS EN 16620:2015EN 16620:2015 (E) 14 Annex B
46、(informative) Precision data The following data were obtained in an interlaboratory test according to ISO 5725-2 4 for collaborative study procedures to validate characteristics of a method of analysis. This method was worked out by the 64 working group Furan-Analytik of the Bundesamt fr Verbraucher
47、schutz und Lebensmittelsicherheit and tested in an interlaboratory study with 15 participants. Table B.1 Precision data for furan in coffee with headspace GC-MS Sample Spray dried coffee Freeze-dried coffee Roasted coffee Preparation of test material naturally contaminated naturally contaminated nat
48、urally contaminated Year of interlaboratory test 2008 2008 2008 Number of laboratories 15 15 15 Number of laboratories retained after eliminating outliers 13 14 15 Number of outliers (laboratories) 2 1 0 Number of accepted results 13 14 15 Mean value, x , g/kg 264 1 140 2 840 Repeatability standard
49、deviation sr, g/kg 19,1 85,1 242,1 Repeatability relative standard deviation, RSDr,% 7,2 7,5 8,5 Repeatability limit r r = 2,8 sr, g/kg 53,5 238 678 Reproducibility standard deviation sR, g/kg 50,8 185 545 Reproducibility relative standard deviation, RSDR, % 19,3 16,2 19,2 Reproducibility limit R R = 2,8 sR, g/kg 142 517 1 530 HorRat value, according to 5 and 6 0,99 1,04 1,4 BS EN 16620:2015EN 16620:2015 (E) 15 Bibliography 1 FDA-METHOD. “Determination of furan in foods”, h