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1、INTERNATIONAL STANDARD IS0 1442 Second edition 1997-02-01 Meat and meat products - Determination of moisture content (Reference method) Viande et produits base de viande - Dtermination de lhumidit (Mthode de rfrence) This material is reproduced from IS0 documents under International Organization for
2、 Standardization (ISO) Copyright License number iHSllCCi1996. Not for resale. No part of these IS0 documents may be reproduced in any form, electronic retrieval system or otherwise, except as allowed in the copyright law of the country of use, or with the prior written consent of IS0 (Case postale 5
3、6,1211 Geneva 20, Swiizerland, Fax +41 22 734 10 79), IHS or the IS0 Licensors members. Reference number IS0 1442:1997(E) Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 02:49:23
4、 MDTNo reproduction or networking permitted without license from IHS -,-,- Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 t
5、echnical committees. Each member body interested in a subject for which a technical committee has been established 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. IS0 collaborates clos
6、ely with the International Electrotechnical Commission (IEC) 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 Standard requires approval by at least 75
7、 % of the member bodies casting a vote. International Standard IS0 1442 was prepared by Technical Committee ISORC 34, Agricultural food products, Subcommittee SC 6, Meat and meat products. This second edition cancels and replaces the first edition (IS0 1442:1973), which has been technically revised.
8、 Annex A of this International Standard is for information only. O IS01997 All rights reserved. Unless otherwise specified, no pari of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in wri
9、ting from the publisher. International Organization for Standardization Case postale 56 CH-121 1 Genve 20 Switzerland Internet central iso.ch X.400 c=ch; a=400net; p=iso; o=isocs; s=central Printed in Switzerland II Copyright International Organization for Standardization Provided by IHS under licen
10、se with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 02:49:23 MDTNo reproduction or networking permitted without license from IHS -,-,- STD.IS0 1442-ENGL 1977 Y85l1903 Ob98843 91Z INTERNATIONAL STANDARD o IS0 IS0 1442: 1 997( E) Meat and meat products - Determination
11、 of moisture content (Reference method) 1 Scope This International Standard specifies a reference method for the determination of the moisture content of meat and meat products. 2 Definitions For the purposes of this International Standard, the following definitions apply. 2.1 moisture content of me
12、at and meat products: Loss in mass obtained under the operating conditions specified in this International Standard, divided by the mass of the test portion. Moisture content is expressed as a percentage by mass. 2.2 test result: The value of a characteristic obtained by carrying out a specified tes
13、t method. IS0 5725-11 3 Principle Thorough mixing of the test portion with sand and drying to constant mass at 103 “C 2 2 “C. 4 Material 4.1 Sand, clean, acid-washed, of a size such that it passes through a sieve of aperture size 1,4 mm and stays on a sieve of aperture size 250 p,m. Dry the sand bef
14、ore use at 150 “C to 160 “C and store in an airtight closed bottle. NOTE - If clean (acid-washed) sand is not available, the sand may be cleaned by the following procedure. Wash the sand with running water. Boil the sand with dilute hydrochloric acid, = 1,19 g/rnl, diluted (1 + I), for 30 min while
15、stirring continuously. Repeat the boiling operation with another portion of the acid until the acid no longer turns yellow after boiling. Wash the sand with distilled water until the test for chloride is negative. For storage, dry the sand at 150 “C to 160 O C . 5 Apparatus Usual laboratory apparatu
16、s and, in particular, the following. 5.1 Mechanical or electrical equipment capable of homogenizing the laboratory sample. This includes a high- speed rotational cutter, or a mincer fitted with a plate with holes not exceeding 4,O mm in diameter. 5.2 Flat dish, made of porcelain or metal (e.g. nicke
17、l, aluminium, stainless steel), of diameter at least 60 mm and height about 25 mm. 5.3 Thin glass rod, flattened at one end, slightly longer than the diameter of the dish (5.2). 5.4 Drying oven, electrically heated, capable of operating at 103 “C I 2 OC. 1 Copyright International Organization for St
18、andardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 02:49:23 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 1442:1997(E) 5.5 Desiccator, containing an efficient desiccant, such as silica gel. 5.
19、6 Analytical balance, capable of weighing to the nearest 0,001 g. o IS0 6 Sampling It is important that the laboratory receive a sample which is truly representative and has not been damaged or changed during transport or storage. Sampling is not part of the method specified in this International St
20、andard. A recommended sampling method is given in IS0 3100-1. Proceed from a representative sample of at least 200 g. Store the sample in such a way that deterioration and change in composition are prevented. 7 Preparation of test sample Homogenize the laboratory sample with the appropriate equipmen
21、t (5.1). Take care that the temperature of the sample material does not rise above 25 OC. If a mincer is used, pass the sample at least twice through the equipment. Fill a suitable airtight container with the prepared test sample, close the container and store in such a way that deterioration and ch
22、ange in composition are prevented. Analyse the test sample as soon as practicable, but always within 24 h after homogenization. 8 Procedure NOTE - If it is required to check whether the repeatability limit (10.2) is met, carry out two single determinations in accordance with 8.3 under repeatability
23、conditions. 8.1 Preparation of the dish and sand Transfer to the dish (5.2) a quantity of sand (4.1) equal to three to four times the mass of the test portion (see 8.2) and dry the dish, sand and glass rod (5.3) for 30 min in the oven (5.4) set at 103 “C. Allow the dish with its contents and the gla
24、ss rod to cool in the desiccator (5.5) to room temperature and weigh to the nearest 0,001 g (mo). 8.2 Test portion Transfer between 5 g to 8 g of the prepared test sample (clause 7) to the prepared dish (8.1) and weigh the dish with its contents and the glass rod to the nearest 0,001 g (rnl). 8.3 De
25、termination 8.3.1 Mix the contents of the dish by means of the glass rod (5.3). NOTE - In cases of difficulty in mixing the test portion with sand, ethanol may be added as necessary. In this case, the ethanol should be evaporated gently before drying the sample in the oven. Heat the dish with its co
26、ntents and the glass rod for 2 h in the oven (5.4) ser at 103 OC. Remove the dish with its contents and the glass rod from the oven and place them in the desiccator (5.5). Allow the dish, its contents and the glass rod to cool to room temperature, then weigh to the nearest 0,001 g. 8.3.2 Repeat the
27、heating, cooling and weighing operations specified in 8.3.1 until the results of two successive weighings (mp), separated by 1 h of heating, do not differ by more than 0,l % of the mass of the test portion. 2 Copyright International Organization for Standardization Provided by IHS under license with
28、 ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 02:49:23 MDTNo reproduction or networking permitted without license from IHS -,-,- o IS0 STD.ISO L942-ENGL L777 I p Y851703 Llb788Y5 775 IS0 1442:1997(E) 9 Expression of results Calculate the moisture content, w, as a per
29、centage by mass, using the following equation: where t710 is the mass, in grams, of the dish, rod and sand (8.1); nil is the mass, in grams, of the dish containing the test portion, rod and sand, before drying (8.2); m2 is the mass, in grams, of the dish containing the test portion, rod and sand, af
30、ter drying (8.3.2). Report the result rounded to one decimal place. 10 Precision 10.1 Interlaboratory test Details of an interlaboratory test on the precision of the method are given in ref. 3. The values derived from this interlaboratory test may not be applicable to concentration ranges and matric
31、es other than those given. 10.2 Repeatability The absolute difference between two independent single test results, obtained using the same method on identical test niaterial in the same laboratory by the same operator using the same equipment within a short interval of time, should not be greater th
32、an the value of r given by the formula r = 0,593 /O + 0,001 7 W where W is the mean moisture content of both results, expressed as a percentage by mass. 10.3 Reproducibility The absolute difference between two single test results obtained using the same method on identical test material in different
33、 laboratories with different operators using different equipment, should not be greater than the value of R given by the formula. R = 0,797 Yo + 0,004 71 W where tL; is the mean moisture content of both results, expressed as a percentage by mass. 11 Test report The test report shall specify -the met
34、hod in accordance with which sampling was carried out (if known); -the method used; -the test result(s) obtained; and - if the repeatability has been checked, the final quoted result obtained. It shall also mention all operating details not specified in this International Standard, or regarded as op
35、tional, together with details of any incidents which may have influenced the result. The test report shall include all information necessary for the complete identification of the sample. 3 Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA
36、Technical Standards 1/9972545001 Not for Resale, 04/27/2007 02:49:23 MDTNo reproduction or networking permitted without license from IHS -,-,- STD*ISO LLIlZ-ENGL L777 LI851703 Ob788Yb b2L I IS0 1442:1997(E) o IS0 Annex A (i n f o r m a t ive) Bibliography l IS0 31 00-1 :1991, Meat and meat products
37、- Sampling and preparation of test samples - Part 1: Sampling. 2 IS0 5725-1 :1994, Accuracy (trueness and precision) of measurement methods and results - Part 1: General principles and definitions. 3 Nordic Committee on Food Analysis (NMKL), No. 23, 3rd edn., 1991. Available from NMKL, Statens Tekni
38、ska Forskningscentral, Livmedelslaboratoriet, SF-O2150 Esbo, Finland. 4 Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 02:49:23 MDTNo reproduction or networking permitted withou
39、t license from IHS -,-,- STD-IS0 1442-ENGL 1977 Y851903 Obl8817 5b0 E IS0 1442: 1 997( E) o IS0 ICs 67.1 20.1 O Descriptors: agricultural products, animal products, food products, meat, meat products, tests, determination of content, water, reference methods. Price based on 4 pages Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/27/2007 02:49:23 MDTNo reproduction or networking permitted without license from IHS -,-,-