6541 (ISO International Standard INTE RNATIONAL ORGANIZATION FOR STANDARDIZATIONMEXAYHAPOAHAR OPrAHW3AuMR IO CTAHAAPTW3AUWWORGANISATION INTERNATIONALE DE NORMALISATION Agricultural food products Determination of crude fibre content - Modified Scharrer method Produits agricoles alimentaires -- Détermination de I'indice d'insoluble dit 《cellulosiquew MethodedeScharrermodifiée First edition - 1981-06-01 UDC 664 : 543.868 Ref. No. ISO 6541-1981 (E) (3) 6541-1981 Descriptors : agricultural products, food products, cereal products, tests, determination, indexes (ratios), insoluble matter. SO Price based on 4 pages Copyright International Organization for Standardization ted without license from IHS Not for Resale Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards institutes (Iso member bodies). The work of developing Inter- national Standards is carried out through ISo technical committees. Every member and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISO Council. International Standard ISO 6541 was developed by Technical Committee ISO/TC 34, Agricultural food products, and was circulated to the member bodies in September 1979. Portugal Austria Hungary Brazil India Romania Bulgaria Israel South Africa, Rep. of Canada Korea, Rep. of Spain Cyprus Libyan Arab Jamahiriya Thailand Malaysia Turkey Czechoslovakia Egypt, Arab Rep. of Mexico United Kingdom Ethiopia Netherlands USSR France Yugoslavia New Zealand Germany, F.R. Poland No member body expressed disapproval of the document. This International Standard has also been approved by the International Union of Pure and Applied Chemistry (IUPAC). - This International Standard is based on Standard No. 113 of the International Associ- NOTE ation for Cereal Chemistry (ICC). International Organization for Standardization, 1981 ? Printed in Switzerland ed without license from IHS Not for Resale ISO 6541-1981 (E) INTERNATIONAL STANDARD Agricultural food products - Determination of crude fibre content - Modified Scharrer method Scope 1 6.1 Scharrer reagent, consisting of a mixture having the following composition : This International Standard specifies a conventional method for - acetic acid solution, prepared by diluting 730 g the determination of the crude fibre content of agricultural food of 96 % (m/m) glaciai acetic acid with water to products. 1 000 g 900 ml nitric acid, concentrated, 020 = 1,38 g/ml 60 ml 2 Field of application 24 g - trichloroacetic acid, crystalline The method is applicable to cereals and cereal products, as well as to certain products containing less than 1 % of crude fibre, 6.2 Acetone. application of Iso 5498. 6.3 Diethyl ether. 3 Reference 6.4 Sea sand, prepared as follows. Sieve the sand successively through sieves of wire gauze of ISO 5498, Agricultural food products -- Determination of crude aperture sizes 160 μm and 125 μm, complying with the re fibre content - General method. quirements of ISo 3310/1. 4 Definition Boil the sand retained by the 125 μm aperture size sieve for 30 min in 4 mol/1 hydrochloric acid solution. Rinse the sand crude fibre content : Conventionally, the whole of the with water until the rinsing water is free from chloride, as in- dicated by the absence of a reaction with silver nitrate solution, substances which are insoluble and combustible under the and incinerate in the muffle furnace (7.9) at 550 ± 25 °C to operating conditions described in this International Standard. constant mass (usually at least 6 h are required). 6.5 Boiling aid : crushed porcelain. content of the product. NOTE -- In French, the term "indice d'insoluble dit cellulosique" has Apparatus brute"". Usual laboratory apparatus, and in particular 7.1 Grinding device, easy to clean, suited to the nature of 5 Pri