1、BRITISH STANDARD BS 4325-5: 1978 Methods for Analysis of oilseed residues Part 5: Determination of diethyl ether extract UDC 633.85:665.3.002.68:543.832:547.272.1BS4325-5:1978 This British Standard, having been prepared under the directionof the Oil and Fats Standards Committee was published under t
2、he authority ofthe Executive Board on 29December1978 BSI 10-1999 First publishedJuly1968 First revisionDecember1978 The following BSI references relate to the work on this standard: Committee reference OFC/24 Draft for approval 78/50361 ISBN 0 580 10473 7 Cooperating organizations The Oils and Fats
3、Standards Committee, under whose direction this BritishStandard was prepared, consists of representatives from the following Government department and scientific and industrial organizations: Chemical Industries Association Chemical Society, Analytical Division* Department of Industry, Laboratory of
4、 the Government Chemist* Greater London Council Lard Association Margarine and Shortening Manufacturers Association* Overseas Development Administration Tropical Products Institute* Royal Institute of Public Health and Hygiene Seed Crushers and Oil Processors Association* Soap and Detergent Industry
5、 Association* United Kingdom Renderers Association Ltd. The organizations marked with an asterisk in the above list, together with the following, were directly represented on the committee entrusted with the preparation of this British Standard: Association of Fatty Acid Distillers British Food Manu
6、facturing Industries Research Association British Resin Manufacturers Association Co-operative Wholesale Society Ltd. Federation of Gelatine and Glue Manufacturers Limited Federation of Oils, Seeds and Fats Association Ltd. Ministry of Agriculture Fisheries and Food National Linseed Oil Processors A
7、ssociation Oil and Colour Chemists Association Rubber Growers Association Society of Chemical Industry United Kingdom Glycerine Producers Association Amendments issued since publication Amd. No. Date of issue CommentsBS4325-5:1978 BSI 10-1999 i Contents Page Cooperating organizations Inside front co
8、ver Foreword ii 0 Introduction 1 1 Scope and field of application 1 2 References 1 3 Definition 1 4 Principle 1 5 Reagents and materials 1 6 Apparatus 1 7 Procedure 1 8 Expression of results 2 9 Notes on procedure 2 10 Test report 2 Publications referred to Inside back coverBS4325-5:1978 ii BSI 10-1
9、999 Foreword This Part of BS 4325, which was prepared under the direction of the Oils and Fats Standards Committee, constitutes the first revision of BS 4325-5:1968. It is identical with ISO 736 “Oilseed residues Determination of diethyl ether extract”, except for changes in clauses 0, 1, 2, 7.1.1,
10、8.1.2 and 10. In clauses 1 and10 the words “International Standard” have been replaced by “BritishStandard”. Clause2 and the sampling instructions given in 7.1.1 have been altered because the ISO text refers to a sampling standard which is not yet available. In clauses 0, 2 and 8.1.2 the references
11、to International Standards have been replaced by references to British Standards. The text of the International Standard has been used as the basis of this BritishStandard; therefore certain conventions are not identical with those normally used in British Standards; attention is especially drawn to
12、 the following. The comma has been used as a decimal marker. In British Standards it is current practice to use a full point on the baseline as the decimal marker. Important note. Attention is drawn to Statutory Instrument 1973 No 1521 (Agriculture. The Fertilisers and Feeding Stuffs Regulations 197
13、3) and to Statutory Instrument 1976 No 840 (Agriculture. The Fertilisers and Feeding Stuffs (Amendment) Regulations 1976), which control the sale of oilseed residues and compound cakes or meals intended for animal feeding purposes in the UnitedKingdom and prescribe methods for determining specified
14、analytical characteristics. Where differences exist between these methods and those given in this British Standard the latter may be used only for purposes which do not fall within the scope of the Statutory Instruments. Additional information. A sieve complying with the requirements of BS410 “Speci
15、fication for test sieves” will satisfy the requirement in6.3. A Soxhlet extractor complying with the requirements of BS 2071 “Soxhlet extractors” will satisfy the requirement in6.5 A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards a
16、re responsible for their correct application. 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, pagesi andii, pages1 and2, an inside back cover and a back cover. This standard h
17、as been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS4325-5:1978 BSI 10-1999 1 NOTEThose parts of the text which differ from ISO736 are indicated by a vertical line in the margin. Otherwise this stand
18、ard is identical with ISO736. 0 Introduction This British Standard was established because the principal users of oilseed residues, namely the manufacturers of animal feeding stuffs, have always determined the oil content of oilseed residues by extraction with diethyl ether and have accumulated a la
19、rge amount of data on the subject. However, as the determination of the oil content of oilseeds is carried out according to BS 4289-3, it was thought necessary that the oil content of oilseed residues should be determined in the same way in order to provide for control of oil production. That method
20、 is therefore the subject of BS 4325-4. The two methods do not always give the same results. 1 Scope and field of application This British Standard specifies a method for the determination of the diethyl ether extract of residues (excluding compounded products) obtained by the extraction of oil from
21、 oilseeds by pressure or solvent. 2 References The titles of the publications referred to in this standard are given on the inside back cover. NOTEAn International Standard, ISO 5500 “Oilseed residues Sampling”, is in course of preparation. It is intended to publish a British Standard dealing with s
22、ampling of oilseed residues at a later date. Until such time, preparation of the contract sample should be in accordance with7.1.1. 3 Definition 3.1 diethyl ether extract the whole of the substances extracted by diethyl ether under the operating conditions specified below 4 Principle Extraction of a
23、 test portion with diethyl ether in a suitable apparatus. 5 Reagents and materials 5.1 Diethyl ether, anhydrous, practically free from peroxides ( 200,712 to 0,716 g/ml, boiling point34,5 C), analytical quality, the non-volatile residue of which at 80 C is not greater than 0,001% (m/m). 5.2 Sand, wa
24、shed with hydrochloric acid and calcined. 5.3 Pumice stone, in small particles, previously dried. 5.4 Sodium sulphate, anhydrous, analytical quality. 6 Apparatus 6.1 Analytical balance 6.2 Mechanical mill, easy to clean and allowing the residues to be ground, without heating and without appreciable
25、change in moisture, volatile matter and oil content, to particles passing completely through the sieve (6.3). 6.3 Sieve, with apertures of diameter 1 mm. 6.4 Extraction thimble and cotton wool, or filter paper. Materials shall be free from matter soluble in diethyl ether. 6.5 Suitable extraction app
26、aratus (capacity of flask200 to 250 ml, for example). 6.6 Electric heating bath (sand bath, water bath, etc.). 6.7 Pestle and mortar, of porcelain, iron or bronze,or, preferably, a suitable mechanical micro-grinder. 6.8 Electrically heated vacuum oven, with thermostatic control. 6.9 Desiccator, cont
27、aining an efficient desiccant. 7 Procedure 7.1 Preparation of the test sample 7.1.1 It is essential to ensure that the contract sample is fully representative of the material under test. (See also note to clause2.) 7.1.2 Grind the contract sample, if necessary, in the previously well-cleaned mechani
28、cal mill (6.2). First, use about one-twentieth of the sample to complete the cleaning of the mill, and reject these grindings; then grind the rest, collect the grindings, mix carefully and carry out the analysis without delay. 7.2 Test portion As soon as grinding is completed, weigh, to the nearest
29、0,01g, about 5 to 10g of the test sample(7.1.2), according to the expected content of extractable matter. 7.3 Preliminary drying Mix the test portion (7.2) in a suitable vessel with2to 3g of the anhydrous sodium sulphate (5.4) per 5g of grindings. Transfer the mixture to a thimble (6.4) and close th
30、is with a plug of cotton wool (6.4). If a filter paper is used, wrap the mixture in it. Mixing may be carried out in the thimble itself.BS4325-5:1978 2 BSI 10-1999 7.4 Determination Weigh, to the nearest 0,001g, the flask of the extraction apparatus (6.5) containing one or two particles of pumice st
31、one (5.3), which have been previously dried at a temperature near 100 C and then allowed to cool for at least1h in the desiccator(6.9) to ambient temperature. Put the thimble or filter paper containing the test portion into the extractor. Pour into the flask the necessary quantity of the diethyl eth
32、er (5.1). Fit the flask to the extractor on the electric heating bath(6.6) and carry out the heating so that the extraction rate is at least 3 drops per second (boiling briskly but not violently). After extraction for 4h, allow to cool. Remove the thimble from the extractor, and place it in a curren
33、t of air in order to remove the greater part of the solvent impregnating it. Empty the thimble into a mortar (6.7), add about10g of the sand (5.2) and triturate as finely as possible (if a micro-grinder is used, grind without adding sand). Put the mixture back into the thimble and put the latter bac
34、k into the extractor. Extract again for2h, using the same flask (see9.1 and 9.2). Expel the greater part of the solvent from the flask by distillation on a boiling-water bath. Continue to remove solvent by carefully turning the flask, until only traces are left. Expel the last traces of solvent by h
35、eating the flask at 75 C for 1,5h in the vacuum oven (6.8) (pressure 133mbar maximum) (except as provided for in9.3). Allow the flask to cool in the desiccator (6.9) for a least 1h to ambient temperature, and weigh to the nearest 0,001g. Carry out a second heating for30min under the same conditions,
36、 cool again and weigh. The difference between these two weighings should not exceed 0,01g. If it does, heat again for periods of30min until the difference in mass does not exceed 0,01g. Record the last weighing of the flask. Carry out two determinations on the same test sample. 8 Expression of resul
37、ts 8.1 Method of calculation and formulae 8.1.1 The diethyl ether extract, expressed as a percentage by mass of the sample as received, is equal to where Take as the result the arithmetic mean of the two determinations, provided that the requirement concerning repeatability (see8.2) is satisfied. Ot
38、herwise, repeat the determination on two other test portions. If this time the difference again exceeds0,2g per100g of sample, take as the result the arithmetic mean of the four determinations carried out. Report the result to one decimal place. 8.1.2 If requested, the diethyl ether extract may be e
39、xpressed in relation to the dry matter by multiplying the result obtained in accordance with8.1.1 by where U is the percentage by mass of moisture and volatile matter determined as specified in BS 4325-1. 8.2 Repeatability The difference between the results of two determinations carried out simultan
40、eously or in rapid succession by the same analyst should not exceed 0,2g of diethyl ether extract per 100g of sample. 9 Notes on procedure 9.1 For most oilseed residues, a single extraction for6h, without an additional trituration, gives equivalent results, but it is the responsibility of the analys
41、t to confirm this in each particular case. 9.2 The solution obtained in the extraction flask should be clear. If it is not, filter it through a filter paper, collecting the filtrate in another flask which has been previously dried and weighed, and wash the first flask and the filter paper several ti
42、mes with diethyl ether. Expel the solvent and dry the residue as described in7.4. 9.3 In the case of residues rich in volatile acids (residues of copra, palm-kernel, etc.), the extract should be dried at 60 C and at atmospheric pressure. 10 Test report The test report shall show the method used and
43、the result obtained, indicating clearly whether this is expressed in relation to the product as received or in relation to the dry matter. It shall also mention any operating conditions not specified in this BritishStandard, or regarded as optional, as well as any circumstances that may have influen
44、ced the result. The report shall include all details required for complete identification of the sample. m 0 is the mass, in grams, of the test portion(7.2); m 1 is the mass, in grams, of the extract in the extraction flask at the last weighing. m 1 100 m 0 - 100 100U -BS4325-5:1978 BSI 10-1999 Publ
45、ications referred to BS 4289, Methods for the analysis of oilseeds. BS 4289-3, Determination of n-hexane extract (or light petroleum extract), called “oil content” (ISO 659) 1) . BS 4325, Methods for the analysis of oilseed residues. BS 4325-1, Determination of moisture and volatile matter content (
46、ISO 771). BS 4325-4, Determination of n-hexane extract (or light petroleum extract), called “oil content” (ISO 734) 1) . 1) Revision in course of preparation; referred to in Introduction only.BS 4325-5: 1978 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independe
47、nt national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or revision. Users of BritishStandards should make sure that they posse
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