1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58neutral detergent fibre content (aNDF)The European Standard EN ISO 16472:2006 has the status of a B
2、ritish StandardICS 65.120Animal feeding stuffs Determination of amylase-treated BRITISH STANDARDBS EN ISO 16472:2006BS EN ISO 16472:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 April 2006 BSI 2006ISBN 0 580 48241 3The British Standa
3、rds which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.This p
4、ublication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations.Summary of pagesThis document comprises a front cover, an inside front co
5、ver, the EN ISO title page, the EN ISO foreword page, the ISO title page, pages ii to iv, pages 1 to 16, an inside back cover and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsA li
6、st of organizations represented on this committee can be obtained on request to its secretary.Cross-referencesenquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.National forew
7、ordThis British Standard is the official English language version of EN ISO 16472:2006. It is identical with ISO 16472:2006.The UK participation in its preparation was entrusted to Technical Committee AW/10, Animal feeding stuffs, which has the responsibility to: aid enquirers to understand the text
8、; present to the responsible international/European committee any EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 16472April 2006ICS 65.120English VersionAnimal feeding stuffs - Determination of amylase-treated neutraldetergent fibre content (aNDF) (ISO 16472:2006)Aliments des animaux - Dtermi
9、nation du contenu en fibredtergente neutre traite lamylase (ISO 16472:2006)Futtermittel - Bestimmung des amylase-behandeltenneutral gereinigten Fasergehalts (ISO 16472:2006)This European Standard was approved by CEN on 23 March 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regul
10、ations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This Europ
11、ean Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national
12、 standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.E
13、UROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 16472:2006: EForeword Th
14、is document (EN ISO 16472:2006) has been prepared by Technical Committee ISO/TC 34 “Agricultural food products“ in collaboration with Technical Committee CEN/TC 327 “Animal feeding stuffs - Methods of sampling and analysis“, the secretariat of which is held by NEN. This European Standard shall be gi
15、ven the status of a national standard, either by publication of an identical text or by endorsement, at the latest by October 2006, and conflicting national standards shall be withdrawn at the latest by October 2006. According to the CEN/CENELEC Internal Regulations, the national standards organizat
16、ions of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovaki
17、a, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 16472:2006 has been approved by CEN as EN ISO 16472:2006 without any modifications. EN ISO 16472:2006Reference numberISO 16472:2006(E)INTERNATIONAL STANDARD ISO16472First edition2006-04-15Animal feeding st
18、uffs Determination of amylase-treated neutral detergent fibre content (aNDF) Aliments des animaux Dtermination du contenu en fibre dtergente neutre traite lamylase EN ISO 16472:2006ii iiiContents Page Foreword iv 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 1 4 Principle. 1 5 Reag
19、ents 2 6 Apparatus 2 7 Sampling 3 8 Preparation of test sample. 3 9 Procedure 4 9.1 Procedure for traditional method as described in Reference 1 4 9.2 Determination using Fibertec-type apparatus . 5 9.3 Modifications for specific types of samples 7 9.4 Quality assurance. 8 10 Calculation and express
20、ion of results 8 10.1 Calculation. 8 10.2 Expression of results . 9 11 Precision 9 11.1 Interlaboratory test . 9 11.2 Repeatability 9 11.3 Reproducibility 10 12 Test report . 10 Annex A (informative) Results of interlaboratory test 11 Annex B (informative) Standardization of heat-stable alpha-amylas
21、e working solution 14 Bibliography . 16 EN ISO 16472:2006iv 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 commit
22、tees. 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 In
23、ternational 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
24、 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
25、subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 16472 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 10, Animal feeding stuffs. EN ISO 16472:20061Animal feeding stuffs Determination of amylase-treated neutr
26、al detergent fibre content (aNDF) WARNING The use of this International Standard may involve the use of hazardous materials, operations and equipment. This International Standard does not purport to address all the safety risks associated with its use. It is the responsibility of the user of this In
27、ternational Standard to establish appropriate safety and health practices and determine the applicability of local regulatory limitations prior to use. 1 Scope This International Standard specifies methods for the determination of amylase-treated neutral detergent insoluble fibrous residue content i
28、n all types of animal feed. It includes a gravimetric routine method and a reference method. 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 edit
29、ion of the referenced document (including any amendments) applies. ISO 6498, Animal feeding stuffs Preparation of test samples 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 amylase-treated neutral detergent fibre content aNDF content mass f
30、raction of insoluble fibre residues determined by the procedure specified in this International Standard NOTE The aNDF content is expressed as a percentage by mass. 4 Principle Neutral detergent (ND) solution and heat-stable alpha-amylase are used to dissolve the easily digestible proteins, lipids,
31、sugars, starches and pectins in feeds, leaving an insoluble fibrous residue that is primarily cell wall components of plant materials (cellulose, hemicellulose and lignin) and indigestible nitrogenous matter in animal products. EN ISO 16472:20062 5 Reagents Use only reagents of recognized analytical
32、 grade, unless otherwise specified, and distilled or demineralized water or water of equivalent purity. 5.1 Sodium sulfite, anhydrous (Na2SO3). 5.2 Dried hominy corn (corn grits, raw), ground to pass through a 1 mm screen in a cutter mill. 5.3 Iodine solution, containing 2 g of potassium iodide and
33、1 g of iodine in 100 ml of water. Store the solution in an amber or opaque bottle. 5.4 Heat-stable alpha-amylase, as a solution or a water extract of lyophilised enzyme powder (approx. 1 g of powder extracted in 100 ml of water). EXAMPLE Termamyl 120 l from Novo Enzymes or equivalent. Standardize th
34、e heat-stable alpha-amylase solution or enzyme powder extract so that two additions of 2 ml will remove starch from 0,5 g of raw corn starch (5.2). For a detailed procedure on standardizing heat-stable alpha-amylase solution, see Annex B. 5.5 Neutral-detergent (ND) solution Pour between 400 ml and 5
35、00 ml of water into a 1 l flask. Add 4,0 g of sodium hydroxide (NaOH) 14,6 g of EDTA, 4,56 g of sodium hydrogen phosphate (Na2HPO4), and 6,81 g of sodium borate decahydrate (Na2B4O710 H2O) and mix until dissolved (heat if necessary). The NaOH and EDTA may be replaced with 18,6 g of disodium EDTA. Un
36、der a safety hood, add 30 g of sodium lauryl sulfate and, after dissolution, add 10 ml of triethylene glycol (anti-foaming aid). Add water to about 950 ml and mix. Adjust the pH to between 6,95 and 7,05 with concentrated hydrochloric acid (HCl) or sodium hydroxide (NaOH) and dilute to 1 000 ml with
37、water. If the pH is off the range by more than 0,5, discard the solution. Store the ND solution at room temperature. If precipitation occurs, warm the solution to 25 C and mix before use. Record the date the ND solution was prepared, the pH measurements and any adjustments in a reagent log book. 6 A
38、pparatus Usual laboratory apparatus and, in particular, the following. 6.1 Analytical balance, capable of weighing to the nearest 0,1 mg, with a readability of 0,1 mg. 6.2 Cyclone mill with 2 mm screen, or cutter mill with 1 mm screen, capable of grinding samples to obtain a geometric mean particle
39、size of 220 m to 260 m 6.3 Refluxing apparatus, with individual heating units and cold water condensers that fit 600 ml flasks. Any conventional apparatus suitable for crude fibre determinations is acceptable. Calibrate the heating unit settings so that 50 ml of water boils within 4 min to 5 min whe
40、n using cold water condensers. A Fibertec type apparatus may be used and should boil 50 ml of water within 10 min. 6.4 Fritted-disc Gooch crucibles, coarse porosity (pore size 40 m to 60 m) crucibles, high-form, 40 ml to 50 ml capacity, or P2 (pore size 40 m to 100 m), 26 ml to 28 ml capacity. EN IS
41、O 16472:20063Clean new crucibles and ash at 500 C for 1 h. Clean crucibles after each use by ashing at 500 C for 3 h, removing ash, inverting in a detergent solution and sonicating for 7 min to 10 min. Rinse crucibles in hot water, and soak in water at room temperature for at least 30 min. Fit the t
42、op of each crucible with a rubber stopper fitted with a port that is connected to a trap and vacuum line. Back-flush each crucible with water, by repeatedly plunging and removing the bottom of the crucible into water to create a vigorous rinsing action. Occasionally check the filtration rate as foll
43、ows. Fill each crucible with 50 ml of distilled water (25 ml for Fibertec P2 crucibles) and record the time required to drain completely without vacuum (should be 180 s 60 s for Gooch or 75 s 30 s for P2). If the drain time is 240 s (or 105 s for P2), clean the crucible with acid or alkaline cleanin
44、g solution (see Reference 1). If cleaning does not improve the filtration rate, discard the crucible. Instead of P2 crucibles, stainless-steel metal crucibles with a 90 m aperture stainless-steel metal sieve may also be used. 6.5 Vacuum filter manifold (e.g. Fibertec type), that allows adequate soak
45、ing of fibrous residues. The manifold should provide a vacuum-tight seal with the crucible to reduce foam formation in vacuum lines. Use thick-walled vacuum tubing to connect the manifold to a trap (4 l to 18 l) and vacuum source. A vacuum reservoir (18 l) between the trap and vacuum source is recom
46、mended to ensure adequate vacuum capacity to remove the foam. 6.6 Boiling water supply Use a continuous boiling water generator as described in Reference 1 or a suitable alternative. The apparatus shall be capable of supplying boiling water ( 95 C) in a quantity sufficient for all samples being wash
47、ed at one time, through a nozzle producing a fine stream (flow rate of 35 ml to 40 ml per 10 s; a 2,5 ml disposable plastic pipette tip makes an acceptable nozzle). A fine nozzle minimizes the water needed to transfer particles to the crucible, but provides the water pressure needed to remove residu
48、es attached to the side of the flask. It is critical that water is boiling when added to the crucibles, especially for samples containing starches, pectic substances, mucilages or glyco-proteins. For Fibertec type apparatus, use a syringe with a cone-spray nozzle to rinse the condensers and a 60 ml
49、disposable syringe with 12 gauge needle that is 10 cm in length to dislodge any residues adhering to the condensers. 7 Sampling Sampling is not part of the method specified in this International Standard. A recommended sampling method is given in ISO 6497. It is important that the laboratory receive a sample which is truly representative and has not been damaged or changed during transport or storage. 8 Preparation of test sample Prepare the test samples in accordance with ISO 6498. For sample stor
