1、BRITISH STANDARD BS5752-11: 1987 ISO8460:1987 Methods of test for Coffee and coffee products Part11: Instant coffee: determination of free-flow and compacted bulk densities ISO title: Instant coffee Determination of free-flow and compacted bulk densities UDC 633.73+663.93:620.113BS5752-11:1987 This
2、British Standard, having been prepared under the directionof the Food and Agriculture Standards Committee,was published underthe authority of the BoardofBSI and comes into effect on 23December1987 BSI10-1999 The following BSI references relate to the work on this standard: Committee reference FAC/15
3、 Draft for comment85/55659 DC ISBN 0 580 16277 X Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Food and Agriculture Standards Committee (FAC/-) to Technical Committee FAC/15, upon which the following bodies were represented: Associatio
4、n of Public Analysts British Soluble Coffee Manufacturers Association Coffee Trade Federation Ltd. Department of Trade and Industry (Laboratory of the Government Chemist) Food and Drink Federation Institute of Trading Standards Administration Ministry of Agriculture, Fisheries and Food Overseas Deve
5、lopment Administration Tropical Development and Research Institute Amendments issued since publication Amd. No. Date of issue CommentsBS5752-11:1987 BSI 10-1999 i Contents Page Committees responsible Inside front cover National foreword ii 0 Introduction 1 1 Scope and field of application 1 2 Refere
6、nces 1 Section 1. Determination of free-flow bulk density 3 Definition 2 4 Principle 2 5 Apparatus 2 6 Sampling 2 7 Procedure 2 8 Expression of results 2 9 Test report 2 Section 2. Determination of compacted bulk density 10 Definition 3 11 Principle 3 12 Apparatus 3 13 Sampling 3 14 Procedure 3 15 E
7、xpression of results 3 16 Test report 3 Figure 1 Schematic diagram of the apparatus for determining free-flow bulk density 4 Figure 2 Apparatus for determining free-flow bulk density 5 Figure 3 Tapping volumeter for determining compacted bulk density 6 Publications referred to Inside back coverBS575
8、2-11:1987 ii BSI 10-1999 National foreword This Part of BS5752 has been prepared under the direction of the Food and Agriculture Standards Committee. It embodies an agreement, to which the United Kingdom was a party, reached in Subcommittee15, Coffee, of Technical Committee34, Agricultural food prod
9、ucts, of the International Organization for Standardization (ISO). This Part is identical with ISO8460:1987 “Instant coffee Determination of free-flow and compacted bulk densities”. Terminology and conventions. The text of the International Standard has been approved as suitable for publication as a
10、 British Standard without deviation. Some terminology and certain conventions are not identical with those used in British Standards; attention is drawn especially to the following. The comma has been used throughout as a decimal marker. In British Standards it is current practice to use a full poin
11、t on the baseline as the decimal marker. Wherever the words “International Standard” appear, referring to this standard, they should be read as “British Standard”. The symbol “ml” has been used to denote millilitre. In British Standards it is current practice to use the symbol “mL”. A British Standa
12、rd does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references International Standard Corresponding Bri
13、tish Standard ISO787-11:1981 BS3483 Methods for testing pigments for paints PartB10:1982 Determination of tamped volume and apparent density after tamping (Identical) ISO6670:1983 BS6379 Sampling of coffee and coffee products Part2:1984 Methods of sampling instant coffee in cases with liners (Identi
14、cal) Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the insi
15、de front cover.BS5752-11:1987 BSI 10-1999 1 0 Introduction A knowledge of the bulk density of instant coffee is essential to trade in that commodity for it determines the volume occupied by a given mass and hence is an important factor in filling containers correctly and for controlling the mass of
16、instant coffee. Bulk density is defined as the ratio of mass to volume. The volume of a given sample of instant coffee varies, according to its history of handling, due to compaction (reversible) and powder breakdown (irreversible) effects. Bulk densities can be expressed in two ways: free-flow dens
17、ity and compacted density. Instant coffee is friable and subject to irreversible powder breakdown effects which may occur with repeated determinations of the compacted density. Because both bulk densities (and in particular the compacted density) depend so critically on the methods used for handling
18、, it is particularly important that the methods adopted for their measurement be as simple and as independent of the human factors as possible. It is also important that any mechanical apparatus needed is standardized, cheap, and easily available throughout those parts of the world where instant cof
19、fee is produced, blended, reprocessed and packed. 1 Scope and field of application This International Standard specifies two methods for the determination of the bulk density of instant coffee: a) free-flow bulk density (section1); b) compacted bulk density (section2). 2 References ISO787-11, Genera
20、l methods of test for pigments and extenders Part11: Determination of tamped volume and apparent density after tamping. ISO6670, Soluble coffee in cases with liners Sampling. BS5752-11:1987 2 BSI 10-1999 Section 1. Determination of free-flow bulk density 3 Definition For the purposes of this Interna
21、tional Standard, the following definition applies. free-flow bulk density (of instant coffee) the ratio of the mass of instant coffee to the volume it occupies (mass per unit volume) after it has been poured freely into a receptacle under the conditions specified in this International Standard it is
22、 conventionally expressed in grams per millilitre 4 Principle Pouring a sample through a specified funnel into a specified receptacle of known volume and weighing the contents of the receptacle. 5 Apparatus 5.1 Balance, accurate to0,1g. 5.2 Apparatus for determination of free-flow bulk density, havi
23、ng the dimensions shown in Figure 1 and the arrangement shown in Figure 2, and consisting of the following parts. 5.2.1 Funnel, made of stainless steel, firmly mounted on a support attached to a rigid base. The exact dimensions shall conform to those given in Figure 1. 5.2.2 Measuring receptacle, cy
24、lindrical, made of stainless steel, of approximate capacity205ml. The capacity of the receptacle shall be known to the nearest millilitre. The exact dimensions shall conform to those given in Figure 1. The distance between the bottom of the funnel and the top of the receptacle shall be kept constant
25、 at40,0 1,5mm. 5.3 Spatula, or other suitable implement having a straight edge. 6 Sampling See ISO6670, in particular Annex B. 7 Procedure WARNING On account of the hygroscopic character of instant coffee, the determination should not be carried out in a humid atmosphere, for example higher than60%
26、relative humidity. The use of an effective dehumidification unit is therefore recommended. 7.1 Weigh the measuring receptacle(5.2.2) to the nearest0,1g. Pour the laboratory sample from its container into the funnel(5.2.1), allowing it to flow freely into the measuring receptacle(5.2.2) until the lat
27、ter overflows. Remove the excess instant coffee, using the spatula or other suitable implement(5.3) to form a plane surface level with the top of the measuring receptacle. Avoid moving, shaking or vibrating the measuring receptacle before the excess instant coffee has been removed. Remove the measur
28、ing receptacle and weigh the measuring receptacle and its contents to the nearest0,1g. 7.2 Carry out two determinations on the same laboratory sample or on two different laboratory samples if the size of the laboratory sample available is insufficient to carry out two separate determinations. 8 Expr
29、ession of results 8.1 Method of calculation and formula The free-flow bulk density, expressed in grams per millilitre, is equal to where m 1is the mass, in grams, of the measuring receptacle; m 2is the mass, in grams, of the measuring receptacle full of instant coffee; V is the capacity, in millilit
30、res, of the measuring receptacle. Take as the result the arithmetic mean of the values obtained in the two determinations(7.2), provided that the requirement for repeatability (see8.2) is satisfied. If it is not, the determinations shall be repeated. 8.2 Repeatability The difference between the valu
31、es obtained in the two determinations(7.2), carried out in rapid succession by the same operator on the same laboratory sample (however,see7.2) using the same apparatus, shall not exceed2% of the mean. 9 Test report The test report shall show the method used and the results obtained. It shall also m
32、ention any operating details not specified in this International Standard, or regarded as optional, together with details of any incidents likely to have influenced the results. The test report shall include all the information necessary for the complete identification of the sample. m 2 m 1 V -BS57
33、52-11:1987 BSI 10-1999 3 Section 2. Determination of compacted bulk density 10 Definition For the purposes of this International Standard, the following definition applies. compacted bulk density (of instant coffee) the ratio of the mass of instant coffee to the volume it occupies (mass per unit vol
34、ume) after it has been subjected to a fixed number of taps (usually300) under the conditions specified in this International Standard it is conventionally expressed in grams per millilitre 11 Principle Determination of the volume of a given mass of instant coffee after a fixed number of taps (usuall
35、y300) in a tapping volumeter. 12 Apparatus 12.1 Balance, accurate to0,1g. 12.2 Tapping volumeter, as specified in ISO787-11 (see also Figure 3), comprising the following parts. 12.2.1 Graduated measuring cylinder, made of glass, of capacity250ml and graduated in divisions of2ml. 12.2.2 Holder, for t
36、he measuring cylinder(12.2.1), with a shaft. 12.2.3 Cam, which lifts the shaft of the holder and the measuring cylinder once per revolution and which has a frequency of rotation of250 15min 1 . 12.2.4 Anvil, on which the raised shaft falls from a height of3 0,1mm. 12.2.5 Counter, to count the number
37、 of revolutions of the cam. 12.2.6 Sleeve, to guide the shaft, constructed of a suitable material to give minimum friction. 13 Sampling See ISO6670, in particular Annex B. 14 Procedure WARNING On account of the hygroscopic character of instant coffee, the determination should not be carried out in a
38、 humid atmosphere, for example higher than60% relative humidity. The use of an effective dehumidification unit is therefore recommended. 14.1 Set the tapping volumeter(12.2) to give300taps. Weigh25,0g of the laboratory sample to the nearest0,1g and transfer to the graduated measuring cylinder(12.2.1
39、). Attach the cylinder to the tapping volumeter by means of the holder(12.2.2), and allow the volumeter to tap300times. Read the volume of the instant coffee from the cylinder to the nearest2ml. 14.2 Carry out two determinations on the same laboratory sample. 14.3 In cases where it is suspected that
40、 the instant coffee may be subject to breakdown, the volume may be determined using a series of50tap sequences to establish whether there is a limiting minimum volume, or whether the volume diminishes continuously. In the latter case, record all the volumes measured. By agreement between the interes
41、ted parties, the compacted bulk density may be recorded as that derived from the volume after the first100taps or any other number of taps. 15 Expression of results 15.1 Method of calculation and formula The compacted bulk density, expressed in grams per millilitre, is equal to where m is the mass,
42、in grams, of the test portion; V is the volume, in millilitres, occupied by the test portion after compaction. Take as the result the arithmetic mean of the values obtained in the two determinations(14.2), provided that the requirement for repeatability (see15.2) is satisfied. If it is not, the dete
43、rminations shall be repeated. 15.2 Repeatability The difference between the values obtained in the two determinations(14.2), carried out in rapid succession by the same operator on the same laboratory sample using the same apparatus, shall not exceed2% of the mean. 16 Test report The test report sha
44、ll show the method used and the results obtained. It shall also mention any operating details not specified in this International Standard, or regarded as optional, together with details of any incidents likely to have influenced the results. The test report shall include all the information necessa
45、ry for the complete identification of the sample. m V -BS5752-11:1987 4 BSI 10-1999 Figure 1 Schematic diagram of the apparatus for determining free-flow bulk densityBS5752-11:1987 BSI 10-1999 5 Figure 2 Apparatus for determining free-flow bulk densityBS5752-11:1987 6 BSI 10-1999 Figure 3 Tapping vo
46、lumeter for determining compacted bulk densityBS5752-11:1987 BSI 10-1999 Publications referred to See national foreword.BS5752-11: 1987 ISO8460:1987 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards
47、. 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 possess the latest amendments or editions. It is the constant ai
48、m 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 BritishStandard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover. Tel:020899
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