ISO INTERNATIONAL STANDARD 7514 First edition 1990-10-01 Instant tea in solid form --- Determination of total ash The soluble sous forme solide -- Determination des cendres totales Referencenumber ISO7514:1990(E) pyIHS underlic Not for Resale ISO 7514:1990(E) Foreword IsO(theInternationalOrganizationforStandardization)isaworldwide federation of national standards bodies (Iso member bodies).The work of preparing international Standards is normally carried out through iso technical committees. Each memberbody interested in a subject for which atechnical committee has been established has the right to be represented on that committee. International organizations, govern- mental 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 standardization. Draft International Standards adopted by the technical committees are bodies casting a vote. International Standard IsO7514was prepared byTechnicai Committee ISO/TC 34, Agricultural food products. ISO 1990 or by any means, electronic or mechanical, including photocopying and microfim, without permissioninwritingfromthepublisher. International Organization for Standardization Case Postale 56·CH-1211Geneve 20·Switzerland Printed in Switzerland CopyrightInternational Organization for Standardization itted without license from IHS Not ftr Resale ISO 7514:1990(E) INTERNATIONAL STANDARD Instant tea in solid form --- Determination of total ash 1 Scope 5 Reagent This International Standard specifies a method for 5.1 Hydrochloric acid, concentrated solution the determination of the total ash of instant tea in (p20 = 1,16 g/ml to 1,18 g/ml), of recognized ana- solid form. lytical grade. WARNING Concentrated hydrochloric acid sol- ution is corrosive, has an irritant vapour and causes Normative references burns; it shall be handled in accordance with good laboratory practice. The following standards contain provisions which through reference in this text, constitute provisions Apparatus of this International Standard. At the time of publi- cation, the editions indicated were valid. All stan- Usual laboratory apparatus and, in particular, the dards are subject revision, and parties to following. agreements based on this International Standard are encouraged to investigate the possibility of ap- 6.1 Dish, of approximately 50 ml capacity, made of plying the most recent editions of the standards in- platinum, porcelain or any other material unaffected dicated below. Members of IEC and ISO maintain by the conditions of the test. registers of currently valid International Standards. 6.2 Furnace, capable of being controlled at Iso 7513:1990, Instant tea in solid form -- Determi- 550 °C ± 25 °C. nation of moisture content (loss in mass at 103 °C) Iso 7516:1984, Instant tea in solid form -- Sampling. 6.3 Hot-plate, thermostatically controlled 6.4 Desiccator, containing an efficient desiccant Definition 7 Sampling 3 For the purposes of this International Standard, the Sampling shall have been carried out in accordance following definition applies. withSO7516. total ash: The residue obtained after treatment with 8 Preparation of the test sample hydrochloric acid and incineration 550 °C ± 25 ° under the conditions specified in Thoroughly mix the instant tea sample as received this International Standard. by shaking or inverting the sealed sample container. 9 Procedure 4Principle 9.1 Preparation of the dish Destruction of organic matter by treatment with Ensure that the dish (6.1) is completely clean, and concentrated hydrochloric acid solution and heating then heat it in the furnace (6.2) at 550 °C ± 25 °C at 550 °C. Weighing of the residue. for at least 30 min. Cool in the desiccator (6.4). After for Standardization 1 No reproduction or networking permitted without license from IHS Not for Resale