500 1099e50 E06t55h E6 2*1d 2t% 051 ISO INTERNATIONAL STANDARD 8128-2 First edition 1993-07-01 Apple juice, apple juice concentrates and drinks containing apple juice Determination of patulin content - Part 2: Method using thin-layer chromatography Jus de pommes, concentres de jus de pommes et boissons a base de jus de pommes Determination de la teneur en patuline Partie 2: Méthode par chromatographie sur couche mince Referencenumber ISO8128-2:1993(E) Copyright International Organization for Standardizatior Not for Resale 1h1 2099e50 E0659h E6 2*1d 279 051 ISO 8128-2:1993(E) 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 committees. Each member body interested in a subject for which a technical committee has been established has the right to be collaborates closely with the International Electrotechnical Commission (lEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International a vote. International Standard ISO 8128-2 was prepared by Technical Committee ISO/TC 34, Agricultural food products, Sub-Committee SC 3, Fruit and vegetableproducts. Iso 8128 consists of the following parts, under the general title Apple juice, apple juice concentrates and drinks containing apple juice - Deter mination ofpatulin content. Part 1:Method using high-performance liquid chromatography Part 2: Method using thin-layer chromatography Annex A of this part of ISO 8128 is for information only. @ISO1993 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without per- mission in writing from the publisher. International Organization for Standardization CasePostale56·CH-1211Geneve20·Switzerland Printed in Switzerland i No reproduction or networking permitted without license from IHS Not fr Resale I0 8128 T*2 93 4851903 0538803 988 INTERNATIONAL STANDARD ISO 8128-2:1993(E) Apple juice, apple juice concentrates and drinks containing apple juice -- Determination of patulin content : Part 2: Method using thin-layer chromatography Scope 3.2 Developing solvents, for two-directional TLC: This part of ISO 8128 specifies a method using thin- benzene/methanol/acetic acid (80 % by mass layer chromatography for the determination of the mixture (19:2:1 by volume); patulin content of apple juice, apple juice concentrates and drinks containing apple juice. toluene/ethyl acetate/formic acid (90 % by mass) mixture (5:4:1 by volume). The limit of detection of the method is 25 μg/l, based on 50 ml of ready-to-drink apple juice. 3.3 Silica gel, for column, chromatography. of NOTE1 For more precise analyses or in case of a dis. 0,063 mm to 0,2 mm particle size. pute, the HPLC method specified in ISO 8128-1 should be used. 3.4 Eluting solution, toluene/ethyl acetate mixture (75:25 by volume). 2 Principle 3.5 Patulin standard solution (C,HO4). Extraction of patulin in a mixture of ethyi acetate and chloroform (3:2 by volume). Filtration of the extract 3.5.1 Preparation on a silica-gel column and qualitative and semi quantitative determination by means oftwo directional thin-layer chromatography (TLC). The spots Weigh, to the nearest 0,1 mg, 10,0 mg of patulin in a 100 ml one-mark volumetric flask and dissolve it in are developed using a 3-methyl-2-benzothiazoline hy- drazone (MBTH) hydrochloride solution. ethyl acetate (3.1). Make up to the mark with ethyl acetate. Pipette 100 ml of this solution into another 100 ml Reagents one-mark volumetric flask and make up to the mark with ethylacetate. Use only reagents of recognized analytical grade and The patulin content of this standard solution is water of the purity required for chr