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STD BSI B S EN 12147 ENGL 1777 1b24bb7 Ob217LL 1 2 2 BRITISH STANDARD Method for Determination of titratable acidity of fruit and vegetable juices BS EN 12147 1997 The European Stanhd EN 12147 1996 ha[.]

S T D - B S I B S E N 12147-ENGL 1777 1b24bb7 Ob217LL 2 BRITISH STANDARD BS EN 12147 : 1997 Method for ```,-`-`,,`,,`,`,,` - Determination of titratable acidity of fruit and vegetable juices The European S t a n h d EN 12147 : 1996 has the status of a British Standard ICs 67.160.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Not for Resale S T D - B S I B S EN LZLLi7-ENGL 7 = LbZLIbb7 Ob21712 Ob7 BS EN 12147 :1997 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technid Committee AW/21, Fi-uit and vegetable juices, upon which the followingbodies were represented: British Fniit Juice Irnport~rs’ Association British Retail Consortium British Soft Drinks Association Limited Campden and Chorleywood Food Research Association Department of ?iade and Industry (Laboratory of the Government Chemist) Leatherhead Food Research Associalion Minishy of Agnculture, Fisheries and Food Royal Society of Chemistry @ BSI 1997 ```,-`-`,,`,,`,`,,` - This British Standard, having been prepared under the direction of the Consumer Products and Services Sector Board, was published under the authority of the Standards Board and comes into effect on 15 June 1997 Amendments issued since publication Amd No Date Text affected The following B I references relate to the work on this standard Committee reference Awl21 Draft for comment 91157094 DC ISBN O 580 27424 Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Not for Resale ~ ~ S T D S B S I B S E N 12Lq7-ENGL 7 M Lb2Libb7 Ob217L3 T T BS EN 12147 : 1997 Contents committees responsible National foreword Foreword Text of EN 12147 O BSI 1997 Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS page Inside front cover ii i ```,-`-`,,`,,`,`,,` - Not for Resale BS EN 12147 :1997 National foreword This British Standard has been prepared by Technid Committee AW/21, and is the English language version of EN 12147 : 1996 h i t and wgetablejukes Determ,imt.ion of titratubk acidity, published by the European Committee for standardization (CEN) EN 12147was produced as a result of ink&onal discussions in which the United Kingdom took an active part Cross-references Publication referred to Corresponding British Standard EN IS0 3696 : 1995 BS EN IS0 3696 : 1995 Spec&fht.ionfor waterfor lubomtory use IS0 5725 : 1986, to which informative reference is made in the text, has been superseded by IS0 57251 : 1994, IS0 57252 : 1994, IS0 57253 : 1994, IS0 5725-4 : 1994 and IS0 57254 : 1994 which are identical with BS IS0 5725 Accu(trueness and precision) of r n m s u m t methods and results,BS IS0 57251 : 1994 GerwmL pinciples and definitions, BS IS0 57252 : 1994B& method f o r ỵhe determination of repeutubility aná reproducibility of a standard rneusurernent method, BS IS0 57253 : 1994, Interrnedkte measures of the precìs.ion of a stu&rd measurement method, BS IS0 5725-4 : 1994 B& method for the determination of the trueness of a standard m e a s u m t method, and BS IS0 5725-6 : 1994 Use in practice of accumc2/ values Compliance with a British Standard does not of itself confer immunity from legal obligations Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages to 6, an inside back cover and a back cover ```,-`-`,,`,,`,`,,` - ii Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Q BSI 1997 Not for Resale S T D n B S I B S E N 12LLi7-ENGL 9 Lb2Libb9 Ob21915 878 EN 12147 EUROPEAN STANDARJD NORMì3 EUR0PEE”E 1EuROP- NORM December 1996 ICs 67.160.20 Descriptors: Food products, beverages, fruit and vegetable juices, chemical anaiysis, determination, acidity, titration English version Fruit and vegetable juices - Determinaton of titratable acidity h c h t - und Gemusesaffe - Bestimmung der tittierbmn Saure i’aciditk titrable This European Standard was approved by CEN on 1W5-09 CEN members are bound to compiy with the CENICENELEC hted Regulations which stipuiate the conditions for giving this European Standard the status of a nationai standard without any alteration Uptodate lists and bibliographical references concerning such nationai standards may be obtained on application to the Central Secretariat or to any CEN member This European Standard exists in three official vemions (English,French, German) A version in any other ianguage made by translation under the responsibility of a CEN member into its own language and notified to the Centrai Secretariat has the same status as the officiai versions CENmembers are the nationai standards bodies of Austria, Beigium, Denmark, Finiand, h c e , Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom ```,-`-`,,`,,`,`,,` - Jus de fruits et de légumes - Dékmnimíion de CEN European Committee for Standardization Comité Européen de Normalisaton Europäisches Komitee für Normung Central Secretariat: rue de Stassart 36, B-1060 Brussels O 1996 Copyright reserved to CEN members Ref No EN 12147 : 1996 E Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Not for Resale ~ STD.BSI B S EN LZL47-ENGL 9 L b b b S O b Z L L b 704 Page EN 12147 : 1996 Foreword This European Standard has been prepared by Technical Committee CENmC 174, the secretariat of which is held by AFNOR This European Standard shall be given the status of a national standard,either by publication of an identical text or by endorsement, at the latest by June 1997, and conflicting national standards shall be withdrawn at the latest by June 1997 According to the CENKENELEC interml Regulations, the national standards organizations of the following countries are bound to implement this European Standad Austria, Belgium, Denmark, Fïnlmd, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom Contents Foreword Scope Normative references Defmition and symbol Principle Reagents APPProcedure Calculation Precision Testreport 10 Annexes A (iormative) Bibliography B (ionnative) statistical resuits of the inter-lab0mS-ytest page 3 3 3 4 5 ```,-`-`,,`,,`,`,,` - Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS O BSI 1997 Not for Resale Page EN 12147 : 1996 = - - This European Standard specifies a method for the determination of the tikitable acidity of fniit and vegetable juices and related products Usual laboratory apparatus and, in particular, the following: Normative references 6.2 pH glass electrode This European Standard incorporates by dated or undated reference, provisions from other publications These normative references are cited at the appropriate piaces in the text and the publications are listeà hereafter For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard ordy when incorporated in it by amendment or revision For undated references the l.est edition of the publication referred to applies 6.3 Refmme electrode, e.g calomel electrode Deñnition and symbol ```,-`-`,,`,,`,`,,` - * Apparatus EN EO 3696 : 1995 Waterfor analytkai l.abomtu?y use - Specìfication and test methods IS0 5725 : 1986 PrecLSum of test methods Determination of repeatability and reproducibuity for a standard test method by inter-labomtory tests - * m scope For the purposes of this standard the following defmition applies 3.1 titratable acidity A measure of the content of minerai and organic acids determined by titration, according to this standard 3.2 Symbol For the purposes of this standard the following symbol applies: G substance concentration 6.4 Combination g h s ekctmde, alternatively to 6.2 and 6.3 6.6 Magnetic s t i m 6.6 Burette, 25 mi capacity, graduated in 0,05 mi divisions 6.7 Lcnu fomt beaker (typically 50 mi) 6.8 One-markpipette, 25 ml capacity Procedure 7.1 Preparation of the test sample Nonnally products shall not be pretreated and their anaiysis by this method shall be on a volumetric basis, results being expressed per litre of sample Anaìysis of concentrated products may also be carried out on a volumetric basis, after dilution to a known relative density, in this case, the relative density shall be indicated Based on a weighed sample and taking the djiution factor for analysis into account, the results may also be expressed per kilogram of product In products with a high viscosity and/or a very high content of cells (for exampie pulp), a detemination on the basis of a weighed test sample is the usuitl procedure If the sample contains appreciable quantities of carbon dioxide, degas it by shaking in a st~pperedconical flask and removing the stopper from time to time, or by using vacuum or ultrasound treatment untiì no more gas evolves 7.2 Calibration Principle Potentiometric titration with standard volumetric soàium hydroxide solution to a pH value of €41 Reagents Use onìy reagents of recognized analyticai grade and oniy degassed water in accordance with at least grade of EN IS0 3696 : 1995 6.1 Sodium hydm-, 6.1 p H meter, accurate to at least 0,Ol pH units standard volumetric solution, c (NaOH) = 0,25 moM 6.2 Buffer solutim, of suitable pH Perform two-point calibration of the pH meter at 20 "C using the buffer solution (6.2) with agitation and foliowing the instrument manufacturer's instructions If the pH meter is equipped with a temperature compensation f a d @ , the caiibration can be &ed out at a temperature other than 20 OC, but in any case between 10 "C and 30 "C 7.3 Determination 'II.ansfer at 20 by means of the pipette (6.8),25 ml of the test sample (Vo) into the beaker (6.7) Start the sikrer (6.6) and titrate by means of the burette (6.6) with soàium hydroxide solution (6.1) una a pH of 8,l is obtained Record the amount of solution (VI) used if the pH meter is equipped with a temperature O C , compensation facility, the determination can be carried out at a temperature other than 20 OC, but in any case between 10 "C and 30 "C BSI 1997 Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Not for Resale ~ STD.BS1 B S EN 12147-ENGL 7 L b b b ï Ob21718 ```,-`-`,,`,,`,`,,` - Page EN i2147 : 1996 Cdculation Precision 8.1 Calculation as titratable acidity The titratable acidity CH+,expressed in millimoles of H+ per litre of product, is given by the form& 1Ooox v1xc (1) cH+ = Details of the inter-laboratorytest on the precision of the method are given in annex B The d u e s derived from the inter-laboiatorytest may not be applicable to d y t e concentmiion ranges and matrices other thCui those given in annex B VO 9.1 Repeatability The absolute difference between two single test results found on identicai test material by one operator using the same apparatus within the shortest feasible time interval will exceed the repeability limit r in not more than % of the cases The d u e is: = 1,03 mm01 H+A where Vo is the volume, in milliiitres, of the test portion (see 7.3) (as a rule 25 mi); VI is the volume, in milliiitres, of the sodium hydroxide solution (see 7.3) used for the determination; is the exact concentsaton, in moles per litre, of G the sodium hydroxide solution (6.1) If Vo is 25 ml and c is 0,25 moM, as specified in this European Standard, the titrable acidity CH+, expressed in millimoles of H+ per litre of product, is given by the formuh c H + = v1 x 10 (2) Report the result without a decimal place 8.2 Calculation as acid content It is also possible to calculate the titratable acidity conventionally as acid content expressed in grams per litre of product, by multiplying the formula (8.1) by a factor corresponding to the acid given in table Tgble Factors corresponding to different [acids I Acid I Factor 10,075 0,067 Citric acid, anhydrous 0,064 9.2 Reproducibility The absolute difference between two single test results on identicai test material reported by two laboratories will exceed the reproducibility limit R in not more than5%ofthecases The value is: R = 2,28 mm01 H+A 10 l k s t report I I The test report shall contain the following dah - ali information necessary for the identification of the sample (kind of sample, origin of sample, designation); - a reference to this European Standard -the date and type of sampling procedure (if Iniown); -the date of receipt; -the date of test; - the test resuits and units in which they have been expressed; -whether the repeatability of the method has been verified; - any particular points observed in the course of the test; - any operation not specified in the method or regarded as optional, which might have affected the results Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS O BSI 1997 Not for Resale - ~ ~ S T D - B S I B S E N - E N G L 1797 W L b b b Ob21717 3 Page EN 12147 : 1996 Annex A (informative) Bibliography Determimtion of titmtabie acidity : No 3,1991 In: The CouaCted Analyses of the IntenzatFederation of h i t Juice Producers Loose-leaf edition, as of 1991 Zug: Swiss Fniit Union Annex B (informative) S t a l i s t i d results of the inter-laboratorytest in accordance with IS0 5725 : 1986, the foliowing parameters have been defined in an inter-laboratory test (for iiterature pertaining to the method see annex A) The test was conduced by the Max von Pettenkofer Institute of the Federal Health Office, Food Chemistry Department, Berlin, BRD Year of interlaboratory test: Number of laboratories: Number of samples: 1993; 14; I Sample Number of laboratories retained after elhmmg outliers Number of outliers (laboratories) Number of accepted results Mean value (mmol H+A) Repeatability standard deviation (sr)(mm01H+/l) Repeatabiiity relative standard deviation (RSD,) (%) * * vi I Repeatability limit (r) ( m o l H+A) Reproducibility standad deviation (SR) ( m o l H+A) Reproducibility relative standard deviation (RSDR) (%) Rey>roducibilitylimit (R) (mmol H+A) Sample types: A: apple juice; B apricotnectar; C grapejuice; D: orangejuice; E grapefruitjuice ```,-`-`,,`,,`,`,,` - O BSI 1997 Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Not for Resale A B 13 12 C 13 14 l I 352 l 391 I -41 39 72 82 118 E D 153 13 I l 51 222 I ~ ~ ~ S T D - B S I BS E N 12147-ENGL 1777 m L b b b Ob21720 135 m BS EN 12147 :1997 List of references see national foreword ```,-`-`,,`,,`,`,,` - BSI 1997 O Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Not for Resale S T D - B S I B S EN - E N G L 1777 Lb2Libb7 Ob21721 O71 BS EN 12147 : 1997 BSI - British Standards Institution BSI is the independent national body responsible for preparing British Standards It presents the UK view on standards in Europe and at the international level It is incorporated by Royal Charter Contract requirements A British Standard does not purport to include all the necessary provisions of a contract Users of British Standards are responsible for their correct application Revisions British S t a n h d s are updated by amendment or revision Users of British Standards should make sure that they possess the latest amendments or editions It is the constant aim of BSI to improve the quality of our products and services We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard wouId inform the Secretary of the responsible technical commit&!, the identity of which can be found on the inside front cover Tek 0181 9969o00, Fax: 0181 996 7400 BSI offers members an individual updating service called PLUS which ensures that subscribersautomatidy receive the latest editions of standards Buying standards Orders for all BSI, internationaland foreign standards publications should be addressed to Customer Services, Sales Department at Chiswick Tek 0181 9967000, Fax: 0181 996 7001 In response to orders for international standards, it is BSI policy to supply the BSI implementation of those that have been published as British Standards,unless otherwise requested Information on standards BSI provides a wide range of informaíion on national, European and international standards through its Library, the Standardhe Database, the BSI Information Technology Service (BITS) and its Technical Help to Exporters Service Contact the Information Department at Chiswick Tek 0181 996 7111; Fax: 0181 996 7048 Subscribing members of BSI are kept up to date with standards developments and receive substantialdiscounts on the purchase price of standards For details of these and other benefits contact Customer Services, Membership at Chiswick Tek 0181 9967002; Fax: 0181 996 7001 Copyright This does not preclude the free use, in the c o m of implementing the standard, of necessary detaiìs such as symbols, and size, type or grade designations If these details are to be used for any other purpose than implementation then the prior written permission of BSI must be obtained If permission is granted,the terms may include royalty payments or a licensing agreement Details and advice can be obtained from the Copyright Manager, BSI, 389 Chiswick High Road, London W4 4AL BSI 389 Chiswick High Road London w4 4AL Copyright European Committee for Standardization Provided by IHS under license with CEN No reproduction or networking permitted without license from IHS Not for Resale ```,-`-`,,`,,`,`,,` - Copyright subsists in ali BSI publications BSI also holds the copyright, in the UK, of the publications of the internaiional standardization bodies Except as permitted under the Copyright, Designs and Patents Act 1988no extract may be reproduced, stored in a retrieval system or hmmutkd * in any form or by any means - eledxonic, photocopying, recording or otherwise - without prior written permission from BSI

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