1、July 2017 English price group 14No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 67.050!%h8Y“2692154www.din.deDIN EN
2、 16943Foodstuffs Determination of calcium, copper, iron, magnesium, manganese, phosphorus, potassium, sodium, sulfur and zinc by ICPOES;English version EN 16943:2017,English translation of DIN EN 16943:2017-07Lebensmittel Bestimmung von Calcium, Kupfer, Eisen, Magnesium, Mangan, Phosphor, Kalium, Na
3、trium, Schwefel und Zink mit ICPOES;Englische Fassung EN 16943:2017,Englische bersetzung von DIN EN 16943:2017-07Produits alimentaires Dosage du calcium, du cuivre, du fer, du magnsium, du manganse, du phosphore, du potassium, du sodium, du soufre et du zinc par ICPOES;Version anglaise EN 16943:2017
4、,Traduction anglaise de DIN EN 16943:2017-07www.beuth.deDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.Document comprises 32 pages 06.17 2 A comma is used as the decimal marker. National foreword This document (EN 16943:2017) has b
5、een prepared by Technical Committee CEN/TC 275 “Food analysis Horizontal methods” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was the DIN-Normenausschuss Lebensmittel und landwirtschaftliche Produkte (DIN Standards Committee Food and Agricultural Products), W
6、orking Committee NA 057-01-09 AA “Elements and their chemical species”. The DIN Standard corresponding to the International Standard re ferred to in this document as follows: ISO 5725 (all parts) DIN ISO 5725 (all parts) National Annex NA (informative) Bibliography DIN ISO 5725 (all parts), Accuracy
7、 (trueness and precision) of measurement methods and results DIN EN 16943:2017-07 isEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16943 May 2017 ICS 67.050 English Version Foodstuffs - Determination of calcium, copper, iron, magnesium, manganese, phosphorus, potassium, sodium, sulfur and zinc
8、 by ICP-OES Produits alimentaires - Dosage du calcium, du cuivre, du fer, du magnsium, du manganse, du phosphore, du potassium, du sodium, du soufre et du zinc par ICP-OES Lebensmittel - Bestimmung von Calcium, Kupfer, Eisen, Magnesium, Mangan, Phosphor, Kalium, Natrium, Schwefel und Zink mit ICP OE
9、S This European Standard was approved by CEN on 20 February 2017. 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
10、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
11、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 Mace
12、donia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISA
13、TION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16943:2017 E-EN 16943:2017 (E) 2 Contents Page European foreword . 3 1 Scope
14、4 2 Normative references 4 3 Principle . 4 4 Reagents . 5 5 Apparatus . 7 6 Procedure. 8 6.1 Sample preparation 8 6.2 Optical emission spectrometry with inductively coupled plasma 8 6.2.1 ICP-OES working conditions 8 6.2.2 Determination with ICP-OES . 8 6.3 Quality control of the analysis . 10 7 Cal
15、culation 10 8 Precision 11 8.1 General . 11 8.2 Repeatability 11 8.3 Reproducibility . 11 9 Test report 14 Annex A (informative) Spectral interferences 15 Annex B (informative) Precision Data . 18 B.1 Details on the inter-laboratory study . 18 Bibliography . 30 DIN EN 16943:2017-07 EN 16943:2017 (E)
16、 3 European foreword This document (EN 16943:2017) 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 standard, either by publication of an identical text or
17、 by endorsement, at the latest by November 2017, and conflicting national standards shall be withdrawn at the latest by November 2017. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifyi
18、ng any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav
19、Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. DIN EN 16943:2017-07 EN 16943:2017 (E) 4 1 Sc
20、ope This European Standard describes a method for the determination of calcium, copper, iron, magnesium, manganese, phosphorus, potassium, sodium, sulfur and zinc in different foodstuffs using optical emission spectrometry with inductively coupled plasma (ICP-OES) after pressure digestion. This meth
21、od has been validated in an interlaboratory study according to ISO 5725 1 on infant formula soya based, cheese, chicken meat, wheat flour, apple juice, lobster and milk (see elements ranges Table 1 and validation data in Annex B). HorRat values greater than 2 have been observed for certain analyte/m
22、atrix combinations during the validation study. Table 1 Validated element ranges Element Range mg/kg Calcium 70 to 7178 Copper 0,60 to 16,40 Iron 0,88 to 77 Magnesium 45 to 1 174 Manganese 0,44 to 5,12 Phosphorus 72 to 9 708 Potassium 605 to 14 312 Sodium 11 to 2 220 Sulfur 26 to 8 542 Zinc 0,16 to
23、43,5 At European or International level, vertical standards for the determination of specific minerals can exist, e.g. for milk and milk products or for animal and vegetable fats and oils 2. 2 Normative references The following documents, in whole or in part, are normatively referenced in this docum
24、ent 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 13804, Foodstuffs - Determination of elements and their chemical species - General conside
25、rations and specific requirements EN 13805, Foodstuffs - Determination of trace elements - Pressure digestion 3 Principle After digestion of the sample with the pressure digestion process described in EN 13805, calcium, copper, iron, magnesium, manganese, phosphorus, potassium, sodium, sulfur and zi
26、nc are determined quantitatively with the ICP-OES 2. The digestion solution is nebulized, the aerosol is directed into an inductively coupled argon plasma, where the elements are atomized and excited for radiation. The emission radiation is resolved spectrally and its intensity determined at element
27、-specific wavelengths with a detector system. Ionization interference can be minimized using an ionization buffer. DIN EN 16943:2017-07 EN 16943:2017 (E) 54 Reagents The concentration of the elements to be determined shall be low enough in the reagents and water not to affect the results. 4.1 Nitric
28、 acid, minimum w = 65 % 1, density about 1,4 g/ml 4.2 Hydrochloric acid, w = 30 %, density = 1,15 g/ml 4.3 Hydrogen peroxide, w = 30 % Hydrogen peroxide (4.3) can contain phosphoric acid as a stabilizing agent. Hydrogen peroxide stabilized with phosphoric acid contaminates the samples with phosphoru
29、s and thus leads to incorrect results. 4.4 Caesium chloride solution as ionization buffer, e.g. w = 10 % (see 6.2.2) 4.5 Internal standard, e.g. scandium, ytterbium, yttrium Depending on the matrix, e.g. for samples with high total salt content, the application of an internal standard can be advanta
30、geous in order to reduce physical interference. In doing so, it shall be ensured that no faults from line interference result due to the internal standard. NOTE It has been shown that if an internal standard is used, it is applicable to all elements mentioned in the scope. 4.6 Stock solutions, = 1 0
31、00 mg/l 2per element Calcium, copper, iron, magnesium, manganese, phosphorus, potassium, sodium, sulfur and zinc individual element stock solutions and internal standard used. The individual element stock solutions may not contain any of the elements to be determined here as accompanying substances
32、or impurities, which could affect the correctness of the results. Alternatively, commercial mixed stock solutions can also be used. 4.7 Standard solutions, = 100 mg/l per element Copper, iron, manganese and zinc standard solution, produced by dilution of the respective stock solution (4.6). Pour 10
33、ml of water into a 50-ml volumetric flask, add 2 ml of nitric acid (4.1) and mix. After cooling to room temperature, add exactly 5 ml respectively of the copper, iron, manganese and zinc stock solution (4.6) by pipette and fill up with water to the mark. These standard solutions are stable for at le
34、ast six months. 4.8 Element reference solutions 4.8.1 General The concentrations of the reference solutions indicated in 4.8.3 to 4.8.6 serve as examples and shall be modified corresponding to the instrument sensitivity, the direction of viewing (axial or radial) and the concentration range to be ex
35、amined, if necessary. If possible, the calibration shall be performed in the 1w = mass fraction 2 = mass concentration DIN EN 16943:2017-07 EN 16943:2017 (E) 6 linear range. Minimum 3, in the nonlinear range 5, reference solutions of different concentrations should be prepared for the calibration. T
36、he concentration of the reagents (acids, if applicable ionization buffer and internal standard) shall correspond to the sample measuring solution. For reasons of stability and purity, the phosphorus and sulfur reference solutions should be prepared separately from the multi-element reference solutio
37、ns of the cations. 4.8.2 Preparation of the flask Pour 10 ml to 20 ml of water into a 100-ml volumetric flask, add 10 ml of nitric acid (4.1) and 2 ml of hydrochloric acid (4.2) and mix. After cooling to room temperature, add stock (4.6) and standard solutions (4.7) by pipette. If using an ionizatio
38、n buffer, add 10 ml of 10 % caesium chloride solution (4.4). If using an internal standard (4.5), add the corresponding amount. Alternatively, the ionization buffer and/or the internal standard can be pumped via a Y-piece into the sample flow during the measurement. These reference solutions are sta
39、ble for a month. The following data under 4.8.3 to 4.8.6 serve as examples and shall be adapted corresponding to the device sensitivity and the emission wavelength selected, and the direction of viewing (axial or radial), if necessary. 4.8.3 Reference solution 1 Pipette the following amounts of stoc
40、k solutions (4.6) into the prepared 100-ml volumetric flask (4.8.2): 2,0 ml calcium 3) = 20 mg/l calcium; 1,0 ml magnesium = 10 mg/l magnesium; 2,0 ml potassium = 20 mg/l potassium; 1,0 ml sodium = 10 mg/l sodium; Furthermore, pipette the following amounts of standard solutions (4.7) into the same f
41、lask and fill up to the mark with water: 0,50 ml copper = 0,5 mg/l copper; 0,50 ml iron = 0,5 mg/l iron; 0,50 ml manganese = 0,5 mg/l manganese; 0,50 ml zinc = 0,5 mg/l zinc. 4.8.4 Reference solution 2 Pipette the following amounts of stock solutions (4.6) into the prepared 100-ml volumetric flask (
42、4.8.2): 10,0 ml calcium = 100 mg/l calcium; 5,0 ml magnesium = 50 mg/l magnesium; 10,0 ml potassium = 100 mg/l potassium; 5,0 ml sodium = 50 mg/l sodium. 3) the sign “ means: “which leads to a mass concentration of“ DIN EN 16943:2017-07 EN 16943:2017 (E) 7Furthermore, pipette the following amounts o
43、f standard solutions (4.7) into the same flask and fill up to the mark with water: 2,0 ml copper = 2,0 mg/l copper; 2,0 ml iron = 2,0 mg/l iron; 2,0 ml manganese = 2,0 mg/l manganese; 2,0 ml zinc = 2,0 mg/l zinc. 4.8.5 Reference solution 3 Pipette the following amounts of stock solutions (4.6) into
44、the prepared 100-ml volumetric flask (4.8.2): 20,0 ml calcium = 200 mg/l calcium; 10,0 ml magnesium = 100 mg/l magnesium; 20,0 ml potassium = 200 mg/l potassium; 10,0 ml sodium = 100 mg/l sodium. Furthermore, pipette the following amounts of standard solutions (4.7) into the same flask and fill up t
45、o the mark with water: 5,0 ml copper = 5,0 mg/l copper; 5,0 ml iron = 5,0 mg/l iron; 5,0 ml manganese = 5,0 mg/l manganese; 5,0 ml zinc = 5,0 mg/l zinc. 4.8.6 Reference solutions phosphorus and sulfur Pipette the following amounts of stock solutions (4.6) into the prepared 100-ml volumetric flask (4
46、.8.2) and fill up to the mark with water: 1,0 ml respectively phosphorus and sulfur = 10,0 mg/l phosphorus and sulfur; 5,0 ml respectively phosphorus and sulfur = 50,0 mg/l phosphorus and sulfur; 10,0 ml respectively phosphorus and sulfur = 100,0 mg/l phosphorus and sulfur. 4.9 Zero value solution T
47、he zero value solution contains water, 10 ml of nitric acid (4.1), 2 ml of hydrochloric acid (4.2), if applicable 10 ml caesium chloride solution (4.4) and a corresponding amount of internal standard (4.5) in 100 ml. 5 Apparatus 5.1 General All equipment and labware that come into direct contact wit
48、h the sample and the solutions used shall be carefully pretreated/cleaned corresponding to EN 13804 to minimize the blank value. 5.2 ICP-OES, optical emission spectrometer with inductively coupled argon plasma, sample supply and atomization system as well as device control and evaluation unit. DIN E
49、N 16943:2017-07 EN 16943:2017 (E) 8 6 Procedure 6.1 Sample preparation Mineralize the sample in a pressure digestion corresponding to EN 13805. In the case of dry, powdery or free-flowing materials (water content below 20 %), add 2 ml of water in relation to a test portion of 400 mg, and mix intensively so that the samp
