EN ISO 11085-2015 en Cereals cereals-based products and animal feeding stuffs - Determination of crude fat and total fat content by the Randall extraction method《谷物 谷物基产品和动物饲料 使用Ra.pdf

1、BSI Standards PublicationBS EN ISO 11085:2015Cereals, cereals-based productsand animal feeding stuffs Determination of crude fat andtotal fat content by the Randallextraction methodBS EN ISO 11085:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 11085:20

2、15. It supersedes BS EN ISO 11085:2010 which iswithdrawn.The UK participation in its preparation was entrusted to Technical Committee AW/4, Cereals and pulses.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to includ

3、e all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 83937 5 ICS 67.060 Compliance with a British Standard cannot confer immunity from legal obligations.This Briti

4、sh Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 11085 September 2015 ICS 67.060 Supersedes EN ISO 11085

5、:2010English Version Cereals, cereals-based products and animal feeding stuffs -Determination of crude fat and total fat content by the Randall extraction method (ISO 11085:2015) Crales, produits craliers et aliments des animaux -Dtermination de la teneur en matires grasses brutes et en matires gras

6、ses totales par la mthode dextraction de Randall (ISO 11085:2015) Getreide, Getreideerzeugnisse und Futtermittel - Bestimmung des Rohfettgehalts und des Gesamtfettgehalts mit dem Extraktionsverfahren nach Randall (ISO 11085:2015) This European Standard was approved by CEN on 13 June 2015. CEN member

7、s 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

8、 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 Managemen

9、t 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, Li

10、thuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17,

11、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 ISO 11085:2015 EBS EN ISO 11085:2015EN ISO 11085:2015 (E) 3 European foreword This document (EN ISO 11085:2015) has been prepared by Technical Committee ISO/TC 34

12、 “Foodproducts“ in collaboration with Technical Committee CEN/TC 338 “Cereal and cereal products” thesecretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of anidentical text or by endorsement, at the latest by March 201

13、6, and conflicting national standards shallbe withdrawn at the latest by March 2016. Attention is drawn to the possibility that some of the elements of this document may be the subject ofpatent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patentrights. Thi

14、s document supersedes EN ISO 11085:2010. According to the CEN-CENELEC Internal Regulations, the national standards organizations of thefollowing countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugo

15、slav 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 the United Kingdom. Endorsement notice The text of ISO 11085:2015 has b

16、een approved by CEN as EN ISO 11085:2015 without any modification. BS EN ISO 11085:2015ISO 11085:2015(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 15 Reagents 26 Apparatus . 27 Sampling 38 Procedure. 38.1 Preparation of the test sample 38.2 Test portion 38.3

17、 Preliminary extraction . 38.4 Hydrolysis 48.4.1 General 48.4.2 Hydrolysis with apparatus I (6.2) . 48.4.3 Hydrolysis with apparatus II (6.3) . 48.5 Extraction 59 Calculation and expression of results . 69.1 Determination with preliminary extraction 69.2 Determination without preliminary extraction

18、610 Precision . 610.1 Interlaboratory test. 610.2 Repeatability . 610.3 Reproducibility . 710.4 Critical difference 710.4.1 General 710.4.2 Comparison of two groups of measurements in one laboratory 710.4.3 Comparison of two groups of measurements in two laboratories . 710.5 Measurement uncertainty

19、. 811 Test report . 8Annex A (informative) Results of an interlaboratory test 9Annex B (informative) Comparison of fat contents for the samples used in the interlaboratory test 14Bibliography .16 ISO 2015 All rights reserved iiiContents PageBS EN ISO 11085:2015ISO 11085:2015(E)ForewordISO (the Inter

20、national 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

21、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 st

22、andardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accor

23、dance with the editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directivesAttention 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. Details of an

24、y patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received. www.iso.org/patentsAny trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For a

25、n explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for thi

26、s document is ISO/TC 34, Food products, Subcommittee SC 4, Cereals and pulses.This second edition of ISO 11085 cancels and replaces the first edition (ISO 11085:2008), which has been technically revised.iv ISO 2015 All rights reservedBS EN ISO 11085:2015INTERNATIONAL STANDARD ISO 11085:2015(E)Cereal

27、s, cereals-based products and animal feeding stuffs Determination of crude fat and total fat content by the Randall extraction method1 ScopeThis International Standard specifies procedures for the determination of the fat content of cereals, cereal-based products, and animal feeding stuffs. These pr

28、ocedures are not applicable to oilseeds and oleaginous fruits.The choice of procedure to be used depends on the nature and composition of the material analysed and the reason for carrying out the analysis.Procedure A is a method for the determination of directly extractable crude fats, applicable to

29、 all materials, except those included within the scope of procedure B.Procedure B is a method for the determination of total fats, applicable to all materials from which the oils and fats cannot be completely extracted without prior hydrolysis.NOTE Most cereals, as well as feeds of animal origin, ye

30、asts, potato protein, compound feeds with milk products, glutens, and products subjected to processes such as extrusion, flaking, and heating, yield significantly higher total fat contents when tested by procedure B than by procedure A. See Annex B.2 Normative referencesThe following documents, in w

31、hole 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.ISO 3696, Water for analytical labora

32、tory use Specification and test methodsISO 6498, Animal feeding stuffs Guidelines for sample preparation3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1crude fat contentmass fraction of substances extracted from the sample by the specified proce

33、dure ANote 1 to entry: The crude fat content is expressed as a percentage mass fraction.3.2total fat contentmass fraction of substances extracted from the sample by the specified procedure BNote 1 to entry: The total fat content is expressed as a percentage mass fraction.4 PrincipleFat is extracted

34、using light petroleum as a solvent and the Randall modification of the Soxhlet method. The test portion is submerged in boiling solvent prior to rinsing in cold solvent, reducing the time needed for extraction. The solvent dissolves fats, oils, pigments, and other soluble substances. After ISO 2015

35、All rights reserved 1BS EN ISO 11085:2015ISO 11085:2015(E)extraction, the solvent is evaporated and recovered by condensation. The resulting fat residue is determined gravimetrically after drying.For total fat determination, the sample is treated under heating with hydrochloric acid. Hydrolysis make

36、s chemically or mechanically bound fats accessible to solvent extraction. The mixture is cooled and filtered. The residue is washed and dried and submitted to the above extraction procedure.For total fat determinations of samples with a “high” fat content (i.e. at least 150 g/kg), a preliminary extr

37、action is performed before applying procedure B.5 ReagentsUse only reagents of recognized analytical grade.5.1 Water, complying with the requirements of at least grade 3 of ISO 3696.5.2 Light petroleum (petroleum ether), consisting mainly of hydrocarbons with six carbon atoms, boiling range 30 C to

38、60 C. The bromine value shall be less than one. The evaporation residue shall be less than 20 mg/l.5.3 Glass beads, of diameter 5 mm to 6 mm or silicon carbide chips.5.4 Hydrochloric acid, c(HCl) = 3 mol/l.5.5 Filtration aid, e.g. diatomaceous earth, boiled for 30 min in hydrochloric acid, c(HCl) =

39、6 mol/l, washed with water (5.1) until acid-free, then dried at 130 C.5.6 Acetone.5.7 Cotton wool, defatted.5.8 Fat-free filter paper.6 ApparatusUsual laboratory apparatus and, in particular, the following.6.1 Solvent extraction system, consisting of a 2-stage Randall extraction process unit enablin

40、g solvent recovery, fitted with fluoroelastomer or polytetrafluoroethylene seals compatible with petroleum ether.6.2 Hydrolysis apparatus I, multiple position unit enabling boiling with acid, compatible with the solvent extraction system (6.1), used for hydrolysis according to 8.4.1.6.3 Hydrolysis a

41、pparatus II, consisting of either a beaker of capacity 400 ml and, as a cover, a watch glass of appropriate diameter, or a conical flask of capacity 300 ml with a reflux condenser, used for hydrolysis according to 8.4.2.6.4 Drying oven, capable of being maintained at (103 2) C.6.5 Microwave oven, wi

42、th defrost setting.6.6 Desiccator, containing an efficient desiccant.2 ISO 2015 All rights reservedBS EN ISO 11085:2015ISO 11085:2015(E)6.7 Filter cartridge, adapted to the hydrolysis apparatus used.6.8 Extraction thimbles, of cellulose, free from petroleum ether-extractable products, and stand to h

43、old thimbles.6.9 Extraction cups, of aluminium or glass, compatible with the solvent extraction system (6.1).6.10 Glass thimbles for hydrolysis.6.11 Analytical balance, enabling weighing at 102mg accuracy.6.12 Mill or grinder, fitted with a 1 mm screen or for samples with a fat mass fraction of betw

44、een 15 % and 20 %, a water-cooled knife mill.6.13 Bchner funnel.7 SamplingA representative sample should have been sent to the laboratory. It should not have been damaged or changed during transport and storage.Sampling is not part of the method specified in this International Standard. Recommended

45、sampling methods are given in ISO 24333.8 Procedure8.1 Preparation of the test sampleGrind (6.12) laboratory samples to a particle size 1 mm.For animal feeding stuff, prepare the test sample as specified in ISO 6498.8.2 Test portionThe test portion consists of 1 g to 5 g, m1, of the ground test samp

46、le weighed to the nearest 1 mg.If the fat content of the test sample is higher than 150 g/kg, start the procedure with 8.3 for total fat determination and continue with 8.4 and 8.5.In all other cases, start the procedure with 8.4 for total fat determination (procedure B) and with 8.5 for crude fat d

47、etermination (procedure A).8.3 Preliminary extraction8.3.1 Comply with the manufacturers instructions for the operation of the solvent extraction system (6.1).8.3.2 Add 5 to 10 glass beads (5.3) and place the extraction cups (6.9) in the drying oven (6.4) for at least 30 min at 103 C 2 C. Transfer t

48、he extraction cups to a desiccator (6.6) and cool to room temperature. Weigh the extraction cups and record their mass, m2, to the nearest 0,1 mg. ISO 2015 All rights reserved 3BS EN ISO 11085:2015ISO 11085:2015(E)8.3.3 Weigh the test portion into a glass thimble (6.10), if using hydrolysis apparatu

49、s I (6.2) or into an extraction thimble (6.8) if using hydrolysis apparatus II (6.3).If recommended by the manufacturer, add filtration aid (5.5).8.3.4 Set the temperature to achieve a reflux of light petroleum (5.2) that is 3 drops/s to 5 drops/s (about 10 ml/min). Preheat the instrument and make sure the cooling water for the reflux condenser is turned on. With cooling water at approximately 15 C, the flow should be adjusted to 2 l/min to prevent solvent evaporation from the condensers.8.3.5 Place thimbles containing test portions i