BS 4317-4-1991 Methods of test for cereals and pulses - Determination of impurities size foreign odours insects and species and variety in pulses《谷物和豆类试验方法 第4部分 豆类杂质、粘度、外部气味、昆虫、种和变.pdf

《BS 4317-4-1991 Methods of test for cereals and pulses - Determination of impurities size foreign odours insects and species and variety in pulses《谷物和豆类试验方法 第4部分 豆类杂质、粘度、外部气味、昆虫、种和变.pdf》由会员分享，可在线阅读，更多相关《BS 4317-4-1991 Methods of test for cereals and pulses - Determination of impurities size foreign odours insects and species and variety in pulses《谷物和豆类试验方法 第4部分 豆类杂质、粘度、外部气味、昆虫、种和变.pdf（12页珍藏版）》请在麦多课文档分享上搜索。

1、BRITISH STANDARD BS 4317-4: 1991 ISO 605:1991 Methods of test for Cereals and pulses Part 4: Determination of impurities, size, foreign odours, insects, and species and variety, in pulsesBS4317-4:1991 This British Standard, having been prepared under the directionof the Agriculture andFood Standards

2、 Policy Committee, was published underthe authority of the Standards Board and comes into effect on 28June1991 BSI 10-1999 First published April 1968 Second edition June 1991 The following BSI references relate to the work on this standard: Committee reference AFC/4 Draft for comment 90/50573 DC ISB

3、N 0 580 19836 7 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Agriculture and Food Standards Policy Committee (AFC/-) to Technical Committee AFC/4, upon which the following bodies were represented: Agricultural Engineers Association As

4、sociation of Public Analysts British Edible Pulse Association Department of Trade and Industry (National Weights and Measures Laboratory) Flour Milling and Baking Research Association Food and Drink Federation Grain and Feed Trade Association Home Grown Cereals Authority Institute of Brewing Institu

5、te of Food Science and Technology Intervention Board for Agricultural Produce Ministry of Agriculture, Fisheries and Food NABIM National Association of Commodity Cargo Superintendents and Surveyors National Farmers Union Natural Resources Institute Silsoe Research Institute Society of Chemical Indus

6、try United Kingdom Agricultural Supply Trade Association Ltd. Amendments issued since publication Amd. No. Date CommentsBS4317-4:1991 BSI 10-1999 i Contents Page Committees responsible Inside front cover National foreword ii 1 Scope 1 2 Normative reference 1 3 Sampling 1 4 Preparation of the test sa

7、mple 1 5 Determination of impurities 1 6 Determination of size (of pulses intended for human consumption) 1 7 Tests for the presence of foreign odours 2 8 Tests for infestation by insects (see also ISO 6639) 2 9 Tests to determine species and variety 2 10 Test report 4 Annex A (informative) Bibliogr

8、aphy 5 Publication(s) referred to Inside back coverBS4317-4:1991 ii BSI 10-1999 National foreword This revision of this Part of BS 4317has been prepared under the direction of the Agriculture and Food Standards Policy Committee. It is identical with ISO605:1991 “Pulses Determination of impurities, s

9、ize, foreign odours, insects, and species and variety Test methods”, published by the International Organization for Standardization (ISO), and in the preparation of which the UnitedKingdom played a full part. This revision differs from BS4317-4:1968, which is superseded and withdrawn, principally i

10、n that additional methods have been included (determination of size, test for presence of foreign odour, tests for infestation by insects, and tests to determine species and variety). These tests were previously included in BS4317-5to BS4317-8inclusive, which have been withdrawn. Additional informat

11、ion. With reference to clauses7 to9, water complying with grade3of BS3978 “Specification for water for laboratory use” is suitable. The bibliography (Annex A) contains references to ISO6639-1, ISO6639-2, ISO6639-3and ISO6639-4, which differ technically from the corresponding British Standard, BS4317

12、-18, “Determination of hidden insect infestation”. However, as these references are supplied for information only, their presence does not affect the validity of this Part of BS4317. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards

13、 are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-reference International Standard Corresponding British Standard ISO ISO 951:1979 BS 4511:1980 Methods for sampling pulses (in bags) (Identical) Summary

14、of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1to 6, 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 inside front co

15、ver.BS4317-4:1991 BSI 10-1999 1 1 Scope This International Standard specifies methods not given in other International Standards for testing pulses which have not been processed and which are intended for human consumption or for animal feeding stuffs. 2 Normative reference The following standard co

16、ntains provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investig

17、ate the possibility of applying the most recent edition of the standard indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 951:1979, Pulses in bags Sampling. 3 Sampling The laboratory sample shall have been taken in accordance with ISO951. 4 Pr

18、eparation of the test sample Thoroughly mix the laboratory sample (clause3). 5 Determination of impurities 5.1 Test portion If necessary, reduce the test sample (clause4) using an automatic divider or by quartering by hand, to obtain a test portion, for one determination, of at least200g, except for

19、 butter beans (Phaseolus lunatus L.) and horse beans (Vicia faba L.) for which the test portion shall be at least300g. NOTE 1If the content of impurities is very small, it may be necessary to increase considerably the mass of the test portion. 5.2 Separation Separate the test portion (5.1) into comp

20、onent groups in order to obtain information relevant to the use for which the lot is suitable. Generally the test portion is separated into five groups, as follows: a) seeds typical of the species and variety (see5.2.1); b) seeds typical of the species but of another variety (see5.2.2); c) defective

21、 seeds belonging to the same species (see5.2.3); d) organic impurities (see5.2.4); e) inorganic impurities (see5.2.5). 5.2.1 Seeds typical of the species and variety This group includes all intact sound typical seeds, seeds with a cracked or injured seed coat, seeds slightly damaged by insects and b

22、roken typical seeds larger than one-half their original size. This group may be subdivided if desired. 5.2.2 Seeds typical of the species but of another variety This group includes seeds of varieties which differ significantly in shape, size, colour or appearance from the seeds of the variety under

23、consideration. 5.2.3 Defective seeds belonging to the same species This group includes broken, partially eaten and injured seeds equal to or less than one-half their original size, seeds markedly damaged by insects, and shrivelled, unripe, germinated, rotten, mouldy and diseased seeds. 5.2.4 Organic

24、 impurities This group includes seed coats, parts of stems, pods, leaves, Sclerotia bodies etc., other crop seeds and weed seeds. 5.2.5 Inorganic impurities This group includes lumps of earth, sand, dust, stones, etc. 5.3 Expression of results Report the amount of material in each of the component g

25、roups (generally5.2.1 to5.2.5), as a percentage by mass of the test portion. 6 Determination of size (of pulses intended for human consumption) 6.1 Sizing Carry out the determination of size on pulses falling within the groups described in5.2.1 and5.2.2. According to the species of pulse, use sieves

26、 either with round holes (for example, for peas and lentils) or with suitable elongated holes (for example, for beans). Weigh the amount passing through the sieve with the smallest holes, and the amounts retained on each of the sieves used. 6.2 Expression of results Report the quantity of pulse a) r

27、etained by the sieve with the largest holes; b) in each size range defined by the upper and lower sizes of sieve aperture; c) passing through the sieve with the smallest holes.BS4317-4:1991 2 BSI 10-1999 Express each of these quantities as a percentage by mass of the test portion. 7 Tests for the pr

28、esence of foreign odours 7.1 Procedure 7.1.1 Carry out the examination described in7.1.2 or7.1.3 (a rapid sensitive method) as soon as possible after sampling. 7.1.2 Spread out the sample and smell it. If no strong foreign odour is detected, return the sample to the container and seal it, leave it f

29、or24h and then re-examine the sample. The sample may be further examined during or after grinding. If, after these operations, no foreign odour can be detected with certainty, put about3g to5g of the ground sample into a flask of50ml to100ml capacity. Examine the ground sample heated to a temperatur

30、e not higher than60 C by cautiously moving the open flask over a flame or repeatedly shaking it and immersing it in a water-bath. 7.1.3 Put a small quantity of the ground or unground product in a beaker, pour in some warm water (60 C to70 C) and cover the beaker. After2min to3min decant the water, a

31、nd note whether foreign odours are present. 7.2 Expression of results Report the presence or absence of foreign odours. 8 Tests for infestation by insects (seealso ISO6639) Note the presence of insect pests, especially adults or larvae of the house moth type (for example Endrosis or Hofmannophila sp

32、ecies) or Bruchid beetles, either on sacks or within the bulk of the product. 8.1 Test for visible infestation 8.1.1 Procedure Spread out part of the laboratory sample on a warm plate (about40 C) and cover immediately with a bell jar in order to prevent the escape of insects. NOTE 2In warm climates

33、it may be advisable to cool the sample and then to sieve it quickly using a sieve of aperture size appropriate to the sample and through which the smaller insects will pass. The adult insects can easily be collected in a test tube and, if it is desired to know whether living insects are present, the

34、 closed test tube can be warmed for a few minutes by hand. If no living insects are observed within15min, open if possible100obviously infested seeds to check the possible presence of living or dead insects and larvae. Examine the sample also for webbing produced by the larvae of the house moth and

35、related species. 8.1.2 Expression of results Report the presence of insects, stating the numbers found, whether they are living or dead, the species (if possible) and the stage of development (larvae, adult, etc.). Report also the presence of webbing. 8.2 Chemical test for infestation by Bruchid bee

36、tles of peas and beans 8.2.1 Test solution Use either of the following solutions: a) iodine, 10g/l solution in potassium iodide. Dissolve10g of potassium iodide in water in a500ml flask fitted with a ground glass stopper. Add to the solution5g of crystalline iodine and shake until the latter is comp

37、letely dissolved. Dilute to500ml with water. b) iodine, 20 g/l ethanolic solution (tincture of iodine). Dissolve 10 g of crystalline iodine in500ml of96% (V/V) ethanol. 8.2.2 Procedure Place500seeds on a sieve and immerse the sieve with the seeds in the test solution (8.2.1). Subsequently immerse th

38、e sieve with the seeds in a5g/l potassium hydroxide or sodium hydroxide solution. Take out the sieve with the seeds from the solution and rinse with cold water for20s. NOTE 3The entry openings of the larvae and the points of attack are stained black by this treatment. As soon as possible, examine th

39、e seeds to determine those showing round black spots or stains on their surface. Consider these seeds as infested. NOTE 4It is necessary to carry out the examination as soon as possible since the discoloration will gradually fade. 8.2.3 Expression of results Count the number of seeds with black spot

40、s or stains and express the number determined as a percentage of the number of seeds examined. NOTE 5By agreement between buyer and seller the state of development of the beetles may be determined as follows: open visibly infested seeds and count separately the living and dead insects (larvae, pupae

41、 and adult beetles). 9 Tests to determine species and variety By examination of the seeds, their species and variety can be determined using morphological, physical and chemical methods. 9.1 Determination of rogues in lots of harvest peas (peas for human consumption) Use the morphological method (9.

42、1.1), or, if the two kinds of peas cannot be distinguished in this way, use the chemical method (9.1.2) or the quartz-lamp method (9.1.3). Carry out four tests in parallel.BS4317-4:1991 BSI 10-1999 3 9.1.1 Morphological method NOTE 6The value of harvest peas for human consumption is lowered by the p

43、resence of rogues. Generally, it is not difficult to distinguish them from each other. Examine the seeds to determine the number of rogues present using the following criteria. Harvest peas are, as a rule, light yellow or green, and their hilum has, in almost all cases, a light shade. The seed coat

44、of the rogue is uniformly grey, or shows violet spots or a marbled brown coloration. The hilum is brown or black. 9.1.2 Chemical method Soak the selected seeds in water at room temperature for3h. The test can be accelerated by boiling the seeds for20min instead of soaking them. If the swelling of th

45、e seeds proceeds slowly, extend the period of soaking or boiling as necessary. Score the seed coats of seeds that do not swell. When the seeds have swollen, decant the water and place the seeds in a glass vessel containing a10g/l potassium carbonate solution or a50g/l sodium hydroxide solution. Afte

46、r5min to10min, a dark discoloration (brown or black) can be observed on the rogues or on their hilum, whereas the harvest peas do not change in colour. 9.1.3 Quartz-lamp method WARNING Care should be taken to prevent ultraviolet light from reaching the eyes and other parts of the body. Examine the s

47、eeds under ultraviolet light. The seeds show a blue or pink fluorescence, that of harvest peas being slightly shaded by violet, whereas the rogues show a brownish shade. 9.1.4 Expression of results Take as the result the arithmetic mean of the four determinations, expressed as a percentage of the nu

48、mber of seeds examined. 9.2 Determination of lentil vetch (Vicia sativa var. lentil-sperma) occurring in lentils as an impurity Use the morphological method (9.2.1), or, if the two kinds of seeds cannot be distinguished in this way, use the quartz-lamp method (9.2.2). Carry out four tests in paralle

49、l. 9.2.1 Morphological method Examine the seeds to determine the number of lentil vetch present using the following criteria. Lentil vetches are characterized by rather thick borders of the seeds, by deep centres of the hilum and by a larger hilum than those of the lentils. Lentil seeds have thinner borders and exhibit darker colours along the borders. 9.2.2 Quartz-lamp method WARNING Care should be taken to prevent ultraviolet light from reaching the eyes and other parts of the body. Remove the seed coat from the two flat sides of the seeds and examine them un