U.S. G.S. A.-G.I. Form No. 174 Issued February, 1927 
 
 U. S. Department of Agriculture 
 
 Bureau of Agricultural Economics 
 
 Handbook 
 
 of 
 
 United States Grades 
 
 for 
 
 Rough Rice 
 
 I 
 Revised a$JE»egffii^(3«a2<lBfiyi927 
 
 United States 
 
 Government Printing Office 
 
 Washington 
 
 1927 
 
CONTENTS 
 
 Page 
 Rough rice grades 1 
 
 Class and grade requirements for — 
 
 Honduras, Edith, Fortuna, Caro- 
 lina, Lady Wright, Blue Rose, 
 Early Prolific, and Japan rough 
 
 rice : 1-3 
 
 California Japan rough rice_ 4-5 
 
 Grades for mixed rough rice 6 
 
 Grades for damp and wet rice 7 
 
 Grades for seedy and very seedy rough 
 
 rice 8-9 
 
 Grades for weevily rice 9 
 
 Grades for stained, mud-dragged, and 
 
 musty rice 10 
 
 Milling quality 11 
 
 Definitions 12-14 
 
 Important features of grading rough rice__ 15 
 
 Sampling of rough rice 15-20 
 
 Method of making moisture tests 21-25 
 
 Determination of milling quality 26 
 
 Smith shelling device 26-28 
 
 Bates laboratory aspirator 28-29 
 
 Determination of foreign material and 
 
 finely broken kernels 3 1-34 
 
 Apparatus for grading rough rice — 35-37 
 
U.S.G.S.A.-G.I. Form No. 174 Issued February, 1927 
 
 U. S. Department of Agriculture 
 
 Bureau of Agricultural Economics 
 
 Handbook of 
 United States Grades 
 
 for 
 
 Rough Rice 
 
 As revised 
 Effective March 1, 1927 
 
 COMPILED BY 
 
 E.G.BOERNER 
 I n charge, Grain Investigations 
 
 W.D.SMITH 
 
 In charge, Rice Investigations 
 
 R.M.GEHL 
 Rice Investigations, Grain Division 
 
 United States 
 
 Government Printing Office 
 
 Washington 
 
 1927 
 
ADDITIONAL COPIES 
 
 OF THIS PUBLICATION MAY BE PROCURED FROM 
 
 THE SUPERINTENDENT OF DOCUMENTS 
 
 GOVERNMENT PRINTING OFFICE 
 
 WASHINGTON, D. C. 
 
 AT 
 
 10 CENTS PER COPY 
 
UNITED STATES GRADES FOR 
 ROUGH RICE 
 
 For the purposes of the United States grades 
 for rough rice: 
 
 Rough rice. — Rough rice shall be rice grown 
 in continental United States which contains not 
 less than 50 per cent of kernels of rice from 
 which the hulls have not been removed, and 
 which may contain not more than 50 per cent 
 of matter other than rice and not more than 10 
 per cent of cereal grains of a kind or kinds other 
 than rice. 
 
 HONDURAS ROUGH RICE (CLASS I) 
 
 This class shall include the rices known 
 commercially as Honduras and Mortgage Lifter, 
 and may include not more than 10 per cent of 
 whole kernels of rice of any other class or classes. 
 
 EDITH ROUGH RICE (CLASS H) 
 
 This class shall include the rice known com- 
 mercially as Edith, and may include not more 
 than 10 per cent of w r hole kernels of rice of any 
 other class or classes. 
 
 FORTUNA ROUGH RICE (CLASS TO) 
 
 This class shall include the rice known com- 
 mercially as Fortuna, and may include not more 
 than 10 per cent of whole kernels of rice of any 
 other class or classes. 
 
 CAROLINA ROUGH RICE (CLASS IV) 
 
 This class shall include the rices known com- 
 mercially as Carolina and Storm Proof, and 
 may include not more than 10 per cent of whole 
 kernels of rice of any other class or classes. 
 
 1 
 
LADY WRIGHT ROUGH RICE (CLASS V) 
 
 This class shall include the rice known com- 
 mercially as Lady Wright, and may include 
 not more than 10 per cent of whole kernels of 
 rice of any other class or classes. 
 
 BLUE ROSE ROUGH RICE (CLASS VI) 
 
 This class shall include the rices known com- 
 mercially as Blue Rose, Greater Blue Rose, and 
 Improved Blue Rose, and may include not more 
 than 10 per cent of whole kernels of rice of any 
 other class or classes. 
 
 EARLY PROLIFIC ROUGH RICE (CLASS VH) 
 
 This class shall include the rice known com- 
 mercially as Early Prolific, and may include not 
 more than 10 per cent of whole kernels of rice 
 of any other class or classes. 
 
 JAPAN ROUGH RICE (CLASS VHI) 
 
 This class shall include the rices known com- 
 mercially as Japan, and may include not more 
 than 10 per cent of whole kernels of rice of any 
 other class or classes. This class shall be 
 divided into two subclasses designated as (a) 
 Japan rough rice, and (b) California- Japan 
 rough rice. 
 
 SUBCLASS (A) JAPAN ROUGH RICE 
 
 This subclass shall include all rices known 
 commercially as Japan possessing the charac- 
 teristics of rice of this class as grown east of the 
 Rocky Mountains. 
 
 2 
 
Grade requirements for the classes Hofiduras, 
 Edith, Fort una, Carolina, Lady Wright, Blue 
 Rose, and Early Prolific rough rice, and for the 
 subclass Japan rough rice 
 
 Grade Xo. 1 
 
 l 
 2 
 
 3 
 4 
 5 
 
 G 
 
 Da: 
 kernels 
 
 Total 
 
 ,ct. 
 
 2 
 
 4 
 
 7 
 
 10 
 
 15 
 
 15 
 
 dam- 
 age 
 
 Red 
 rice 
 
 Foreign man : 
 finely broken kernels 
 
 Sepa- 
 rable 
 
 P.ct. 
 
 P.ct. 
 
 0.0 
 
 0.5 
 
 .1 
 
 3.0 
 
 .2 
 
 6.0 
 
 .3 
 
 10.0 
 
 .4 
 
 20.0 
 
 • 5 
 
 CO.O 
 
 I 
 
 2 
 
 4 
 
 7 
 
 10 
 
 15 
 
 15 
 
 Inseparable 
 
 Mud 
 lumps 
 
 0.0 
 
 .1 
 o 
 
 . mi 
 
 .3 
 
 .5 
 
 1.0 
 
 Cereal 
 grains 
 
 P.ct. 
 0.0 
 .1 
 .2 
 .3 
 .5 
 1.0 
 
 Rice of 
 
 other 
 classes 
 
 1 
 2 
 4 
 6 
 1C 
 10 
 
 Sample Sample grade shall be rough rice of the class Ilon- 
 grade. duras, or Edith, or Fortuna, or Carolina, or Lady 
 
 Wright, or Blue Rose, or Early Prolific, or the 
 subclass Japan, respectively, which does not come 
 within the requirements for any of the grades 
 from Xo. 1 to Xo. 6, inclusive, or which has any 
 commercially objectionable foreign odor, or is 
 sour, heating, or hot, or is otherwise of distinctly 
 low quality. 
 
 1 For special grade designations for weevily, damp, wet, seedy, 
 very seedy, mud-dragged, stained, and musty rough rice see 
 specifications given on pp. 7 to 10, inclusive. 
 
 The rough rice in each grade above sample grade shall be cool. 
 
SUBCLASS (B) CALIFORNIA-JAPAN ROUGH RICE 
 
 This subclass shall include all rices known 
 commercially as Japan possessing the charac- 
 teristics of rice of this class as grown wes,t of 
 the Great Plains area of the United States. 
 
Grade requirements for the subclass California' 
 
 Japan rough rice 
 
 
 Damaged 
 
 kernels 
 
 Red 
 
 Fomiin material and 
 
 finely broken kcriul- 
 
 
 Grade No. 1 
 
 Total 
 
 dam- 
 age 
 
 Sepa- 
 rable 
 
 Inseparable l 
 
 Rice of 
 
 other 
 clisses 
 
 
 Mud 
 lumps 
 
 < ''Teal 
 grains 
 
 
 1 
 
 P.ct. 
 
 0.2 
 
 .4 
 
 .7 
 1.0 
 1.5 
 2.0 
 
 P.ct. 
 0.0 
 .1 
 .2 
 .3 
 .4 
 .5 
 
 P.ct. 
 0.1 
 .2 
 .5 
 1.0 
 2.0 
 5.0 
 
 P.ct. 
 
 2 
 
 4 
 
 7 
 
 10 
 
 15 
 
 20 
 
 P.ct. 
 
 0.0 
 .1 
 .2 
 .3 
 .5. 
 
 1.0 
 
 P.ct. 
 
 0.0 
 .1 
 .2 
 .3 
 .5 
 
 1.0 
 
 P.ct. 
 0.1 
 
 2 
 
 .2 
 
 3 
 
 .4 
 
 4 
 
 .6 
 
 5 
 
 1.0 
 
 6 
 
 1.0 
 
 Sample 
 grade. 
 
 Sample grade shall be rough rice of the subclass 
 California- Japan which does not come within 
 the requirements for any of the grades from 
 No. 1 to Xo. 6, inclusive or which has any 
 commercially objectionable foreign odor, or is 
 sour, heating, or hot, or is otherwise of distinctly 
 low quality. 
 
 1 For special grade designations for weevily, damp wet, 
 seedy, very seedy, mud-dragged, stained, and musty rough 
 rice see specifications given on pp. 7 to 10, inclusive. 
 
 The rough rice in each grade above sample grade shall be cool. 
 
GRADES FOR MIXED ROUGH RICE 
 
 Mixed rough rice. — Mixed rough rice shall 
 be a mixture of any two or more of Classes I, 
 II, III, IV, V, VI, VII, and VIII which does 
 not meet the requirements of any one of such 
 classes. 
 
 Mixed rough rice shall be graded according 
 to each of the grade requirements common to 
 the class or subclass of rough rice which pre- 
 dominates over each other class or subclass in 
 the mixture, except that all of the grade require- 
 ments in any class as to the maximum per- 
 centages of other rices shall be disregarded. 
 The grade designation of mixed rough rice shall 
 include, successively, in the order named, the 
 number of the grade, the word " mixed," and, 
 in the order of its predominance, the name and 
 approximate percentage of each class or sub- 
 class of rough rice which constitutes 10 per cent 
 or more of the mixture; but if only one class 
 or subclass exceeds 10 per cent of the mixture 
 the name and approximate percentage of that 
 class or subclass shall be added to the grade 
 designation, followed by the name and approxi- 
 mate percentage of at least one other class or 
 subclass. 
 
 6 
 
GRADES FOR DAMP AND WET ROUGH 
 
 RICE 
 
 DAMP ROUGH RICE 
 
 In the case of rice other than of the subclass 
 California-Japan rough rice all rough rice con- 
 taining more than 14 per cent but not more than 
 15.5 per cent of moisture shall be considered 
 damp. 
 
 In the case of rice of the subclass California- 
 Japan rough rice all rough rice containing more 
 than 15 per cent but not more than 16 per cent 
 of moisture shall be considered damp. 
 
 Damp rough rice shall be graded and desig- 
 nated according to the grade requirements of 
 the grade applicable to such rice if it were not 
 damp, and there shall be added to and made a 
 part of such grade designation the word "damp." 
 
 WET ROUGH RICE 
 
 ill the case of rice other than of the subclass 
 California-Japan rough rice all rough rice con- 
 taining more than 15.5 per cent but not more 
 than 17 per cent of moisture shall be considered 
 wet. 
 
 In the case of rice of the subclass California- 
 Japan rough rice all rough rice containing more 
 than 16 per cent but not more than 17 per cent 
 of moisture shall be considered wet. 
 
 Wet rough rice shall be graded and designated 
 according to the grade requirements of the grade 
 applicable to such rice if it were not wet, and 
 there shall be added to and made a part of such 
 grade designation the word "wet." 
 
 Note. — All rough rics containing more than 17 per cent of 
 moisture shall be considered of low quality and shall be graded 
 "Sample grade." 
 
 24030°— 27 2 <7 
 
GRADES FOR SEEDY AND VERY SEEDY 
 
 ROUGH RICE 
 
 • 
 
 The determination of whether rough rice is 
 seedy, very seedy, or sample grade on account 
 of seeds shall be made after the removal of 
 separable foreign material. 
 
 SEEDY ROUGH RICE 
 
 If, after the removal of separable foreign 
 material, in the case of rice other than of the 
 subclass California-Japan rough rice, rough rice 
 contains more than 0.1 per cent but not more 
 than 0.5 per cent of weed seeds it shall be con- 
 sidered seedy. 
 
 If, after the removal of separable foreign 
 material, in the case of rice of the subclass Cali- 
 fornia-Japan rough rice, rough rice contains 
 more than 0.5 per cent but not more than 1.5 
 per cent of weed seeds it shall be considered 
 seedy. 
 
 Seedy rough rice shall be graded and desig- 
 nated according to the grade requirements of 
 the grade applicable to such rice if it were not 
 seedy, and there shall be added to and made a 
 part of such grade designation the word " seedy." 
 
 VERY SEEDY ROUGH RICE 
 
 If, after the removal of separable foreign 
 material, in the case of rice other than of the 
 subclass California- Japan rough rice, rough 
 rice contains more than 0.5 per cent but not 
 more than 1 per cent of weed seeds it shall be 
 considered very seedy. 
 
 8 
 
If, after the removal of separable foreign 
 material, in the case of rice of the subclass 
 California-Japan rough rice, rough rice contains 
 more than 1.5 per cent but not more than 3 
 per cent of weed seeds it shall be considered 
 very seedy. 
 
 Very seedy rough rice shall be graded and 
 designated according to the grade requirements 
 of the grade applicable to such rice if it were not 
 verv seedv, and there shall be added to and 
 
 ft «. ' 
 
 made a part of such grade designation the 
 words "very seedy." 
 
 Note.— If, after the removal of separable foreign material, in 
 the case of rice other than of the subclass California-Japan 
 rough rice, rough rice contains more than 1 per cent of weed 
 seeds it shall be considered of low quality and shall be graded 
 "Sample grade." If, after the removal of separable foreign 
 material, in the case of rice of the subclass California-Japan 
 rough rice, rough rice contains more than 3 per cent 'of weed 
 seeds it shall be considered of low quality and shall be graded 
 "Sample grade." 
 
 GRADES FOR WEEVILY ROUGH RICE 
 
 Weevily rough rice. — Weevily rough rice 
 shall be all rough rice which is infested with live 
 weevils or other insects injurious to stored rice. 
 
 Weevily rough rice shall be graded and des- 
 ignated according to the grade requirements of 
 the grade applicable to such rice if it were not 
 weevilv, and there shall be added to and made a 
 part of such grade designation the word 
 "weevily," 
 
 9 
 
GRADES FOR STAINED, MUD-DRAGGED, 
 AND MUSTY ROUGH RICE 
 
 STAINED ROUGH RICE 
 
 Stained rough rice shall be rough rice which 
 has been distinctly discolored by climatic con- 
 ditions or in any other manner. 
 
 Stained rough rice shall be graded and desig- 
 nated according to the grade requirements of 
 the grade applicable to such rice if it were not 
 stained, and there shall be added to and made 
 a part of such grade designation the word 
 " stained." 
 
 MUD-DRAGGED ROUGH RICE 
 
 Mud-dragged rough rice shall be rough rice 
 in which there are more than 2 per cent of 
 kernels with a distinct amount of mud clinging 
 to them. 
 
 Mud -dragged rough rice shall be graded and 
 designed according to the grade requirements of 
 the grade applicable to such rice if it were not 
 mud-dragged, and there shall be added to and 
 made a part of such grade designation the word 
 " mud-dragged .' ' 
 
 MUSTY ROUGH RICE 
 
 Musty rough rice shall be rough rice which 
 has an unmistakable musty odor. 
 
 Musty rough rice shall be graded and desig- 
 nated according to the grade requirements of 
 the grade applicable to such rice if it were not 
 musty, and there shall be added to and made 
 a part of such grade designation the word 
 "musty." 
 
 10 
 
MILLING QUALITY 
 
 Milling quality shall be based on the value of 
 the rough rice for milling purp The I 
 
 for milling quality shall be determined by use 
 of the Smith shelling device, described in mimeo- 
 graph circular USGSA-GI, No. 34, dated 
 August, 1925, issued by the Bureau of Agricul- 
 tural Economics, United States Department of 
 Agriculture, or as determined by any device 
 or method giving equivalent result-. 
 
 Milling quality shall be determined as prime 
 milling quality, good milling quality, medium 
 milling quality, fair milling quality, ordinary 
 milling quality, or low milling quality. The 
 milling quality so determined and stated shall 
 be added to the grade designation. 
 
 Examples: Xo. 1 Blue Rose rough rice, prime 
 milling quality. 
 No. 1 Blue Rose rough rice, fair 
 
 milling quality. 
 No. 3 Blue Rose rough rice, ordi- 
 nary milling quality. 
 No. 1 California-Japan rough rice, 
 
 prime milling quality. 
 No. 1 California-Japan rough rice, 
 
 good milling quality. 
 No. 3 California- Japan rough rice, 
 prime milling quality. 
 
 11 
 
DEFINITIONS 
 
 Basis of determinations. — Each determina- 
 tion of general appearance, temperature, odor, 
 moisture, separable foreign material and finely 
 broken kernels, milling quality, mud-dragged, 
 and insects injurious to stored rice shall be on 
 the basis of the lot of rice as a whole. Each 
 determination of red rice, damaged kernels, and 
 other classes shall be upon the basis of the rice 
 after shelling. All other determinations shall 
 be upon the basis of the rice when free from 
 separable foreign material and finely broken 
 kernels and before shelling. 
 
 Percentages. — Percentages, except in the 
 case of moisture, shall be percentages ascertained 
 by weight. 
 
 Percentage of moisture. — Percentage of mois- 
 ture shall be that ascertained by the moisture 
 tester and the method of use thereof described 
 in Bulletin No. 1375, dated February, 1926, 
 issued by the United States Department of 
 Agriculture, Bureau of Agricultural Economics, 
 or that ascertained by any device and method 
 giving equivalent results. 
 
 Damaged kernels. — Damaged kernels shall be 
 kernels and pieces of kernels of rough rice which 
 have been distinctly damaged by water, insects, 
 or by any other means. Sound broken kernels 
 
 12 
 
and kernels of which the hulls only have been 
 damaged shall not be considered as damaged 
 kernels. 
 
 Heat-damaged kernels. — Heat-damaged ker- 
 nels shall be kernels and pieces of kernels of 
 rough rice which have been distinctly discolored 
 by external heat or as a result of heating caused 
 by fermentation. 
 
 Separable foreign material and finely broken 
 kernels. — Separable foreign material and finely 
 broken kernels shall be all matter other than 
 rice which will not pass through a No. 12 sieve 
 and all kernels and pieces of kernels of rough 
 rice and all foreign matter which will pass 
 through a No. 63^2 sieve. 
 
 No. 12 sieve. — A metal sieve perforated with 
 round holes twelve sixty-fourths inch in diameter. 
 
 No. 63^2 sieve. — A metal sieve perforated with 
 round holes six and one-half sixty-fourths inch 
 in diameter. 
 
 Mud lumps. — Mud lumps shall be lumps of 
 dried mud which will pass through a No. 12 
 sieve but which will not pass through a No. 
 63^ sieve. Mud lumps which will not pass 
 through a No. 12 sieve or which will pass through 
 a No. 63^ sieve shall function in grading only 
 as " separable foreign material and finely 
 broken kernels." 
 
 Cereal grains. — Cereal grains shall include 
 barley, rye, wheat, emmer, spelt, einkorn, corn, 
 grain sorghums, and oats, and shall not include 
 buckwheat, flaxseed, and wild oats. Cereal 
 
 13 
 
grains which will not pass through a No. 12 
 sieve or which will pass through a No. 6J^ 
 sieve shall function in grading only as " separable 
 foreign material and finely broken kernels." 
 
 Weed seeds. — Weed seeds shall be grains, 
 kernels, or seeds, either whole or broken, of any 
 plant other than rice or other cereal grains. 
 Weed seeds which will not pass through a No. 12 
 sieve or which will pass through a No. 6J^ 
 sieve shall function in grading only as " sepa- 
 rable foreign material and finely broken 
 kernels." 
 
 Red rice. — Red rice shall be whole or broken 
 kernels of rice of which the bran is distinctly 
 red or pink in color. 
 
 14 
 
IMPORTANT FEATURES OF GRAD- 
 ING ROUGH RICE 
 
 THE SAMPLING OF ROUGH RICE 
 
 The obtaining of a representative sample is 
 essential to the determination of the true grade 
 of a given lot of rough rice. If the sample 
 obtained is not representative no amount of 
 care in making determinations for the grading 
 factors will establish the true grade of the rough 
 rice sampled. Consequently, great care should 
 be taken in sampling in order that the sample 
 on which the grade of the rough rice is to be 
 based shall truly represent the rough rice 
 sampled. 
 
 The sample should be approximately 2 quarts 
 in size. If the time to elapse between the draw- 
 ing of the sample and the determination of 
 grade would permit of such change in the con- 
 dition of the sample as to affect the grade, at 
 least lj/g pints should be inclosed in an air-tight 
 container and the remainder, if any, in a clean 
 cloth sack. 
 
 In the case of bulk rough rice in a carload 
 lot, or in a wagon, at least five probes (with a 
 double-shell compartment trier 60 inches long, 
 or one giving equivalent results), and as many 
 more as may be necessary, in the discretion of 
 the sampler, shall be taken from the rice in 
 different parts of the car or wagon, as the case 
 may be. 
 
 24030°— 27- 
 
 15 
 
In case of bulk rice in a canal boat, barge, 
 ship, or other vessel at least five probes (with 
 a double-shell compartment trier, or one giving 
 equivalent results), and as many more as may 
 be necessary, in the discretion of the sampler, 
 shall be taken at points through each hatch or 
 opening in the deck, or may be drawn from the 
 spout or on the belt or other conveyor from the 
 vessel if taken in such a way as to be repre- 
 sentative of the entire lot or parcel. 
 
 SAMPLING DEVICES 
 
 GRAIN TRIER (PROBE) AND SAMPLING CANVAS 
 
 For obtaining a representative sample from a 
 carload of bulk rice the use of the double tube, 
 separate compartment grain trier (probe) shown 
 in Figure 1 is recommended. 
 
 The use of such a trier makes it possible for 
 the sampler to note any unevenness in loading 
 and to ascertain the approximate location and 
 quantity of any mixture of rice or of dirty, heat- 
 ing, or damp spots, etc., found in any part of the 
 rice. To assist in doing this it is advisable to 
 use a canvas 5 by 2 feet in dimensions on which 
 to empty the grain from the trier. The grain 
 should be emptied lengthwise on the canvas, 
 each separate trierful apart from the others, so 
 that the grain from each compartment can be 
 noted separately. 
 
 In case of bulk rice being loaded aboard a 
 canal boat, barge, ship, or other vessel, the 
 sample may be taken from the spout or on the 
 
 16 
 
Ȥ-/^/v/-* tube 
 
 TER TUBE 
 
 ^ JLoV7 
 
 vv~--^^JL-0/ȣ-/V//VC IN TUBES 
 
 J 
 PARTITION \ 
 
 I 
 
 B 
 
 Fig. 1.— Rice trier (probe). Double-tubed, separate- 
 compartment trier (probe), recommended by the 
 Department of Agriculture. A, Trier closed; B, trier 
 open; C, cross section showing double tubes, D, 
 sectional view; and E, longitudinal view, showing 
 compartments 
 
belt or other conveyor to the vessel if taken in 
 such a way as to be representative of the entire 
 lot or parcel. 
 
 In case of rice in sacks, samples shall be drawn 
 from as many individual sacks selected at ran- 
 dom as will enable the sampler to procure an 
 average and representative sample of the entire 
 lot. In case a lot is of such size or is stacked in 
 such a manner that a representative sample can 
 not be obtained, no official inspection of the rice 
 should be made until a representative portion 
 of it is accessible for sampling. 
 
 In case it shall appear that a material portion 
 of a lot or parcel of rice is in any manner dis- 
 tinctly inferior to the remainder of the lot or 
 parcel, a separate sample otherwise complying 
 with these instructions shall be taken from such 
 portion and from the remaining portion. There 
 shall be filed with such sample a statement show- 
 ing the estimated quantity of each portion of 
 the rice from which each such sample was taken. 
 
 SAMPLE DIVIDER (BOERNER SAMPLER) 
 
 After a representative sample of the lot or 
 parcel of rice to be graded is obtained it is 
 usually necessary to reduce its size considerably 
 in order that the grade may be determined by 
 careful analysis. To reduce the size of a sample 
 of rice containing foreign substances of different 
 specific gravity or size than of the rice with which 
 they are mixed and at the same time obtain a 
 sample as representative as the original is 
 scarcely possible except by mechanical means. 
 
 18 
 
Fig. 2. — Modified Boerner sampler. For use in ob- 
 taining a representative portion from a larger sample 
 for analyses purposes 
 
 19 
 
 I 
 
Figure 2 shows a device, generally referred to 
 as the " Modified Boerner sampler," which will 
 divide a sample into smaller portions and still 
 maintain the proper proportions for the various 
 factors of the original sample. In the operation 
 of this device the rice is placed in a hopper at the 
 top of the machine and released, when it passes 
 through an opening at the bottom of the hopper, 
 down the sides of a cone the point of which is 
 directly under the center of the opening. 
 Around the base of the cone are pockets or open- 
 ings. The rice falling down the sides of the cone 
 is cut into separate streams, which, a little farther 
 on, merge into two streams. Streams Nos. 1, 3, 
 5, etc., unite into one stream which empties into 
 one receptacle, and streams 2, 4, 6, 8, etc., unite 
 into another stream which empties into a second 
 receptacle. 
 
 The device is fully described in United States 
 Department of Agriculture Bulletin No. 857. 
 
 20 
 
METHOD OF MAKING MOISTURE TESTS 
 
 Owing to the numerous methods of making 
 moisture determinations and the wide variations 
 in the results obtained by the different methods 
 the tester and method described in Department 
 of Agriculture Bulletin No. 1375, issued by the 
 Bureau of Agricultural Economics, United 
 States Department of Agriculture, have been 
 designated as the standard on which the grades 
 are based. This in no way precludes the use of 
 other methods of making moisture determina- 
 tions so long as the results are corrected to con- 
 form to those secured by the standard method 
 specified. Figure 3 gives a sectional view of the 
 official standard moisture tester. 
 
 In making moisture tests, use the quantities 
 of oil and grain and extinguish the flame as listed 
 in the following table of specifications: 
 
 21 
 
Kind of grain 
 
 Oil in 
 
 flask 
 
 Rough rice 
 
 Brown rice 
 
 Head rice (milled). 
 Second head rice__ 
 
 Screenings rice 
 
 Brewer's rice 
 
 Wheat 
 
 Shelled corn 
 
 Oats 
 
 Rye 
 
 Grain sorghums. .. 
 
 Barley 
 
 Flaxseed 
 
 C.c. 
 
 150 
 i 150 
 » 150 
 
 1 150 
 
 2 150 
 2 150 
 
 150 
 150 
 150 
 150 
 150 
 150 
 150 
 
 Weight 
 of grain 
 in flask 
 
 Grams 
 100 
 100 
 100 
 100 
 100 
 100 
 100 
 100 
 3 50 
 100 
 100 
 100 
 100 
 
 Extin- 
 guish the 
 flame at — 
 
 C. 
 
 200 
 200 
 200 
 200 
 200 
 200 
 180 
 190 
 195 
 175 
 190 
 190 
 175 
 
 1 Use glass-wool pad 2 inches in diameter and one-fourth inch 
 thick in bottom of flask. 
 
 2 Use double-walled flask. 
 
 3 Use special graduate which is one-half of the volume of the 
 regular graduate; however, the regular graduate may be used 
 by doubling the moisture-test reading. 
 
 Special points for consideration: 
 
 (1) Install the moisture tester in a place where 
 it will not be exposed to strong air currents. 
 
 (2) The standard tester is equipped for heating 
 with illuminating gas. 
 
 (3) Keep the wire gauze with asbestos center 
 in good condition and so adjusted that the flame 
 plays directly in the center of the asbestos. 
 
 (4) Place the flask so that the bottom of the 
 flask is not less than three-eighths of an inch 
 above the wire gauze. 
 
 (5) See that the column of mercury in the 
 thermometer is continuous; if broken, it should 
 be shaken down. 
 
 (6) Thoroughly mix the sample before weigh- 
 ing for tests; and unless the test is to be made 
 immediately upon its arrival in the office place 
 in air-tight container. 
 
 22 
 

 Fig. 3. — Moisture tester. Sectional view of 
 the official moisture tester, showing the 
 various parts properly connected for use; 
 A, Distillation flask in position three-eighths 
 of an inch above the wire gauze 
 
 I 
 
(7) Make tests in duplicate, and if duplicates 
 vary over three-tenths of 1 per cent make an- 
 other test. 
 
 (8) Adjust the thermometers so that four- 
 fifths of the mercury bulb is submerged in the 
 grain and oil after the grain has been placed in 
 the flask. (See to the adjustment each time. 
 Do not guess.) 
 
 (9) Use correctly graduated thermometers 
 and graduates. 
 
 • (10) Do not use mushy rubber stoppers, as 
 they absorb some of the moisture that should 
 pass into the graduates. 
 
 (11) Clean and dry each graduate before 
 using for a test. (Do not let them show any 
 moisture in the bottom or along the sides.) 
 
 (12) Do not use oil directly from the previous 
 test. Empty used flasks into a large storage 
 can and never directly into the oil-measuring 
 device. 
 
 (13) Keep a good circulation of cold water 
 through the condenser tank. 
 
 (14) Adjust the heating apparatus so that the 
 required temperature is reached in 20 minutes. 
 A longer time will give results too low and a 
 shorter time too high. 
 
 (15) If the moisture content of the sample is 
 high so that there is a tendency to boil over, 
 lower the flame until a considerable portion of 
 the water is distilled over. 
 
 (16) Cut off the heat at the exact temperature 
 prescribed for each grain. 
 
 (17) After the flame is extinguished a slight 
 gradual rise in the temperature is to be expected. 
 A sudden increase or sudden decrease in tem- 
 
 24 
 
perature of several degrees indicates that the 
 flame was too intense during the latter part of 
 the heating, and the test should be repeated. 
 
 (18) Do not remove covers nor remove ther- 
 mometers until the temperature recedes to 
 160° C. 
 
 (19) After the temperature has fallen to 160° 
 C. or lower disconnect thermometer and then 
 the deliver}' tube. 
 
 (20) Read the percentage of moisture in the 
 graduated cylinder after all the drops clinging 
 to the sides of the graduates have been shaken 
 down. The reading is taken beneath the layer 
 of oil on top of the water. 
 
 (21) Results of tests need not be expressed 
 more closely than one-tenth of 1 per cent. 
 
 (22) If the water which distills over is dis- 
 colored the substance has evidently been burned 
 and the test should be repeated. 
 
 (23) When the machine is not in use keep 
 the thermometers connected in the flasks and 
 the flasks connected with the distilling tubes in 
 the same manner as for making *a test. 
 
 (24) Before making a test in a new flask or 
 before using a machine that has not been in 
 use for a 24-hour period a test should be made 
 on a preliminary sample so that all the flasks 
 will be uniform in condition. 
 
 (25) Place scales on a firm support and see 
 that they are in balance before making a 
 weighing. 
 
 (26) The specific directions given above and 
 in United States Department of Agriculture 
 Bulletin No. 1375 for making tests do not apply 
 to modified forms of testers. 
 
 25 
 
DETERMINATION OF MILLING QUALITY 
 
 SMITH SHELLING DEVICE 
 
 The Smith shelling device illustrated in 
 Figure 4 is recommended for making shellings 
 of rough rice for the purpose of determining its 
 milling quality. The percentage of admix- 
 tures, red rice, damaged kernels, and other 
 factors in rough rice can also be determined more 
 readily after the hulls have been removed with 
 the shelling device. 
 
 The Smith shelling device is fully described 
 in mimeographed circulars USGSA-GI, Nos. 
 34 and 35, issued by the Bureau of Agricultural 
 Economics, United States Department of Agri- 
 culture. 
 
 In making shellings of rough rice it is recom- 
 mended that the following method be used: 
 
 Use only samples which have been freshly 
 drawn or samples which have been kept in air- 
 tight containers for only a short length of time. 
 The hardness of the kernels in a lot will not be 
 correctly shown by a shelling made of a sample 
 of rough rice which has been allowed to remain 
 in the open air or which has been stored in a 
 paper sack or similar container. 
 
 Use a 50-gram portion of rough rice for the 
 shelling. This portion should be "cut" from 
 the sample by the vse of the modified Boerner 
 sampler illustrated on page 19. Great care 
 should be taken to see that this portion is ac- 
 curately weighed. 
 
 26 
 
^ 
 
 I ^s 
 
 Scale m incha 
 
 I ' 1 1 1 1 I . . I ll) 
 
 i » • • » 'i 
 
 Shaft 
 
 Scale in inches 
 r-r i i i i i i i i i i i 
 
 Fig. 4. — Smith shelling device. Used for rubbing the hulls 
 off from the kernels in samples of rough rice to determine 
 its milling quality, (a) The device assembled on a table. 
 The dotted lines show the position of the device while it 
 is being emptied, (b) Cross section of the base illustrat- 
 ing the hook-up of the rubbing block 
 
 27 
 
Place the 50-gram portion in the shelling 
 device and set the machine in motion by starting 
 the motor. The device is equipped with an 
 automatic cut-off switch which stops the machine 
 after the rice has received 100 rubs. Each 
 portion should receive 200 rubs when testing the 
 rice for milling quality. 
 
 When the machine stops at the end of 200 
 rubs the rubbed rice is removed by dumping 
 the device down over the end of the table and 
 brushing the hulls and rice into a pan fastened 
 to the end of the hopper. Care should be used 
 to see that all of the rice and hulls in the "shell- 
 ing" are brushed into this pan, leaving nothing 
 in the device and without losing any of the 
 kernels or hulls. 
 
 BATES LABORATORY ASPIRATOR 
 
 The Bates laboratory aspirator is recom- 
 mended for use in separating the loose hulls from 
 the " rubbed" rice. This apparatus makes it pos- 
 sible to remove the loose hulls from the shelling 
 without the loss of the finely broken particles of 
 rice. 
 
 After the loose hulls have been removed from 
 the shelling the remaining portion may be ana- 
 lyzed for who leand broken kernels, red rice, and 
 damaged kernels, or any other factor which is 
 more readily determined with the hulls removed. 
 
 Plans and specifications for constructing the 
 Bates laboratory aspirator may be obtained 
 without cost from the Bureau of Agricultural 
 Economics, United States Department of 
 Agriculture. 
 
 28 
 
\RiCE,/ 
 
 Fig. 5. — Bates laboratory aspirator. Used for removing 
 the hulls from rubbed samples (shellings) of rough rice 
 
 29 
 
SIEVES HELPFUL IN DETERMINING MILLING 
 
 QUALITY 
 
 In the determination of whole and broken 
 kernels the use of a No. 6J^ sieve and also a 
 No. 5J^ sieve will be found helpful. Most of 
 the broken kernels can be removed from the 
 shelling with the sieves and the remaining broken 
 kernels can then be readily separated from the 
 whole kernels by hand picking. 
 
 30 
 
METHOD OF DETERMINING FOREIGN 
 MATERIAL AND FINELY BROKEN KER- 
 NELS 
 
 EQUIPMENT FOR MAKING THE SEPARATION 
 
 In determining the quantity of foreign material 
 and finely broken kernels in connection with the 
 grading of rough rice the following equipment is 
 used: 
 
 Set of perforated metal hand sieves. The 
 sieves and bottom pan should be circular in 
 shape and made of aluminum, brass, or other 
 suitable material. The smooth surface of the 
 metal in the sieves should be face up. The 
 metal should be 0.025 to 0.035 inch in thickness. 
 
 (a) Bottom pans: The inside diameter across 
 the top of the pan should be 13% inches; the 
 inside diameter across the bottom of the pan 
 should be 13 inches; depth 2^ inches; and roll 
 at top of pan ^ inch in diameter. 
 
 (6) No. 6^2 sieve: With round perforations 
 six and one-half sixtv-fourths inch in diameter; 
 inside diameter across the top of the sieve should 
 be 13% inches; inside diameter across the bot- 
 tom of the sieve should be 13 inches; depth IJ/g 
 inches; and roll at top of sieve ^ inch in diam- 
 eter. 
 
 (c) No. 12 sieve: With round perforations £f 
 inch in diameter; inside diameter across the top 
 
 31 
 
of the sieve should be 13^4 inches, inside diam- 
 eter across the bottom of the sieve should be 13 
 inches; depth 1% inches; and roll at top of 
 sieve ^ inch in diameter. 
 
 Note. — The No. 6H sieve should be made to nest very freely 
 with the bottom pan. The No. 12 sieve should be made to nest 
 very freely with the No. 6M sieve. 
 
 It is absolutely essential that the dimensions 
 of the perforations of the sieves used be exactly 
 as stated above. A slight variation in the dimen- 
 sions materially influences the percentage of 
 matter which will pass through the sieve. To 
 secure the exact size it is necessary that the per- 
 forations be cut with dies especially made for the 
 purpose. Sieves made from tin or galvanized 
 iron with an ordinary punch will not give accu- 
 rate results. The shape and arrangement of the 
 perforations are shown in Figure 6, and the 
 manner of nesting of the sieves is shown in 
 Figure 7. . 
 
 No 6/ 2 
 
 No.12 
 
 Fig. 6. — Illustrating the perforations (full size) for the 
 No. 6)4 and No. 12 sieves adopted by the United States 
 Department of Agriculture in connection with the 
 grading of rough rice 
 
 32 
 
Fig. 7.— Xest of two sieves and bottom pan. Bottom pan 
 has an inside diameter of 13 inches and is 2j^ inches deep. 
 The No. 6H sieve nests freely with the bottom pan and 
 is lj'8 inches deep. The No. 12 sieve nests freely with 
 the No. 6H sieve and is 1% inches deep 
 
 METHOD FOR MAKING THE DETERMINATION 
 
 The following method for determining foreign 
 material and finely broken kernels in rough rice 
 should be used: 
 
 Not less than 50 grams and preferably 100 
 grams of the original sample should be used for 
 screening. The portion should be shaken on 
 the nest of sieves and bottom pan until it is 
 apparent that no more material will pass through 
 the sieves. 
 
 33 
 
Kernels of rice, either single or in clusters, 
 which remain on the No. 12 sieve after screening 
 should be removed and placed with the rice 
 which remains on the No. 6J^ sieve. 
 
 The mud lumps, cereal grains, weed seeds, and 
 other foreign material remaining on the No. 12 
 sieve after screening and all of the material of 
 every land passing through the No. 6J^ sieve 
 function as separable foreign material and finely 
 broken kernels. 
 
 A representative portion of at least 50 grams 
 of the rice remaining on the No. 6J^ sieve after 
 screening should be analyzed for mud lumps, 
 cereal grains, and weed seeds. Mud lumps and 
 cereal grains, when found in this portion of rice, 
 are grading factors, and the sample should be 
 graded for each of these factors according to the 
 limits prescribed in the grades on pages 3 and 5. 
 Weed seeds, when found in excess of 0.5 per cent 
 for the subclass California- Japan and 0.1 per 
 cent for all other rices, after the removal of 
 separable foreign material determine whether a 
 sample is "seedy" or "very seedy" as stated on 
 pages 8 and 9. 
 
 Great care should be used in sieving the 
 samples as the limits for mud lumps, cereal 
 grains, and weed seeds left in the rice after 
 screening are much more stringent than the 
 limits for separable foreign material and finely 
 broken kernels. In so far as possible the foreign 
 material should be removed with the sieves. 
 
 34 
 
APPARATUS FOR GRADING ROUGH RICE 
 
 To equip laboratories for the grading of rough 
 rice according to the United States grades for 
 rough rice the following equipment is regarded 
 as essential: 
 
 1. Brown- Duvel moisture tester, completely 
 equipped with flasks; certified centigrade ther- 
 mometers to read correctly from 170 to 200°; 
 graduates of 25 c. c. capacity; one-hole rubber 
 stoppers, sizes Xos. 5 and 3; condenser tubes; 
 150 c. c. oil measuring device; supply of oil, etc. 
 (See United States Department of Agriculture 
 Bulletin No. 1375.) 
 
 2. Balance, capacity 500 grams, sensitive to 
 one-tenth gram, wath set of weights, 1 gram to 
 500 grams. 
 
 3. Balance, 'capacity approximately 50 grams, 
 graduated beam to read 1 gram and fractions of 
 a gram, sensitive to one-tenth gram, with set of 
 weights 1 gram to 50 grams. 
 
 4. Sieves and pan for use in the determination 
 of " foreign material and finely broken kernels' ' 
 in rough rice: 
 
 (a) Bottom pan: The inside diameter across 
 the top of the pan should be 13% inches; the 
 inside diameter across the bottom of the pan 
 should be 13 inches; depth 2^ inches; and roll 
 at top of pan ^ inch in diameter. 
 
 (6) No. 63^> sieve: With round perforations 
 six and one-half sixty-fourths inches in diameter; 
 
 35 
 
inside diameter across the top of the sieve should 
 
 be 13% inches; inside diameter across the bottom 
 
 of the sieve should be 13 inches; depth, 1% 
 
 inches; and roll at top of sieve, x§ inch in 
 
 diameter. 
 
 (c) No. 12 sieve: With round perforations 
 
 -Jf inch in diameter; inside diameter across the 
 
 top of the sieve should be 13% inches; inside 
 
 diameter across the bottom of the sieve should 
 
 be' 13 inches; depth, 1% inches; and roll at top 
 
 of sieve ^ inch in diameter. 
 
 Note. — The No. 6K sieve should be made to nest very freely 
 with the bottom pan. The No. 12 sieve should be made to nest 
 very freely with the No. 6^ sieve. 
 
 5. A modified Boerner sampler for correctly 
 dividing a sample into smaller portions for 
 analysis and moisture determinations. (See 
 United States Department of Agriculture 
 Bulletin No. 857.) 
 
 6. Trier for bulk rough rice. The trier should 
 be double-shelled and divided into compartments, 
 and should be 60 inches long. 
 
 7. Sampling canvas, 5 by 2 feet in dimensions, 
 on which to empty the rice from the trier. 
 
 8. Trier for sacked rough rice. 
 
 9. Air-tight containers (sample cans), capacity 
 approximately 450 grams. 
 
 10. Cloth sample bags, waterproofed, capacity 
 at least 2 quarts. 
 
 11. Grain pans, with spout for pouring into 
 other containers. 
 
 12. Smith shelling device, equipped with motor 
 and automatic cut-off switch. 
 
 36 
 
13. Laboratory aspirator for removing loose 
 hulls from shellings of rice. 
 
 In addition to the apparatus listed above, the 
 following equipment will be found convenient 
 and desirable: 
 
 1. Extra moisture-testing equipment: Flasks, 
 thermometers, graduates, rubber stoppers, test- 
 tube cleaners, etc. 
 
 2. Five-gallon oil can equipped with faucet. 
 
 3. Five-gallon oil can equipped with strainer 
 funnel to recover oil. 
 
 4. Five-gallon refuse can. 
 
 5. Small funnel to fit in moisture flasks for 
 pouring sample into the flasks. 
 
 6. Tweezers for mechanical analvsis. 
 
 7. Small grain scoop. 
 
 8. Brush for cleaning up rice and rice dust. 
 
 9. Heavy table for handling samples, analysis, 
 etc. 
 
 10. Furniture, including chairs, stationery 
 supplies, files, etc., to keep proper records. 
 
 FURTHER INFORMATION 
 
 For further information regarding the inspec- 
 tion and grading of rough rice in accordance with 
 the provisions of the United States grades for 
 rough rice apply to any Federal field office of 
 rice investigations or to the Bureau of Agricul- 
 tural Economics, United States Department of 
 Agriculture, Washington, D. C. 
 
 o 
 
 37 
 

UNIVERSITY OF FLORIDA 
 
 3 1262 08930 1 
 
 393 
 
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