(ISO 5515 NTERNATIONAL STANDARD INTERNATIONAL ORGANIZATION FOR STANDARDIZATIONMEXAYHAPOAHAR OPrAHM3AUMA NO CTAHAAPTM3ALWWORGANISATION INTERNATIONALE DE NORMALISATION Fruits, vegetables and derived products - Decomposition of organic matter prior to analysis -- Wet method Fruits, legumes et produits derives -- Décomposition des matieres organiques en vue de I'analyse Methode par voie humide First edition -- 1979-02-01 Ref. No. ISO 5515-1979 (E) UDC 634.1/635 : 543.056 5515-1979( Descriptors : food products, fruits, vegetables, fruit and vegetable products, chemical analysis, determination of content, organic materials, digestion. SO Price based on 3 pages 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 International Standards is carried out through ISO technical committees. Every up 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as Internationa! Standards by the ISO Council. Internationai Standard ISO 5515 was developed by Technical Committee ISO/TC 34, Agricultural food products, and was circulated to the member bodies in November 1976. It has been approved by the member bodies of the following countries : India Poland Australia Austria Iran Portugal Bulgaria Ireland Romania Canada South Africa, Rep. of Israel Chile Korea, Rep. of Spain Mexico Turkey Czechoslovakia France Netherlands United Kingdom Germany, F.R. New Zealand Yugoslavia Hungary Peru Nomemberbodyexpresseddisapprovalofthedocument. @ International Organization for Standardization, 1979 : Printed in Switzerland Copyright International Organization for Standardization ted without license from IHS Not for Resale INTERNATIONAL STANDARD ISO 5515-1979 (E) Fruits, vegetables and derived products -- Decomposition of organic matter prior to analysis -- Wet method 0 INTRODUCTION 4.1 Nitric acid, P20 1,42 g/ml. There are two methods for decomposition of the organic 4.2 Sulphuric acid, P20 1,84 g/ml. matter present in fruits, vegetabies and derived products : a) wet decomposition method, described in this 4.3 Hydrogen peroxide, 30 % (m/m) solution, if necessary International Standard; (see 6.3.2). b) ashing method (see ISO 5516). 4.4 Perchloric acid, P20 1,67 g/ml, if necessary (see 6.4). The specific International Standards on analysis of the products will, if necessary, identify which method to use 4.5 Hydrochioric acid, 5 N solution, if necessary (see 6.4). and any modifications to be made to the method. Dilute 382,5 ml of concentrated hydrochloric acid, P20 1,19 g/ml, to 1 000 ml with water. 1 SCOPE AND FIELD OF APPLICATION 4.6 Ammonium oxalate [(COONH4’2], concentrated This International Standard specifies a method for the solution, approximately 5 g in 100 ml, in the case of decomposition of the organic matter in fruits, vegetables determination of tin (see 6.4). of their mineral (metal) content. 2 REFERENCES ISO 2173, Fruit and vegetable products - Determination 5 APPARATUS of soluble solids content -- Refractometric method. Usual laboratory apparatus, and in particular : Is0 5516, Fruits, vegetables and derived products Decomposition of organic matter prior to analysis -- Ashing 5.1 Kjeldahl flask, 300 ml, made from borosilicate glass method. or silica. 5.2 Digestion rack with controllable heating. 3 PRINCIPLE Heating of the test portion until all organic matter is 'pooh 's decomposed and a clear solution is obtained, either 5.4 Beads made from borosilicate glass. with sulphuric acid and nitric acid and in certain cases with hydrogen peroxide, or 5.5 One-mark volumetric flasks, 50 ml or 100 ml, with sulphuric acid and nitric acid with the addition complying with ISO 1042. of perchlor