EVALUATION OF TWO METHODS FOR SEPARATING HEAD RICE

Transcription

1 EVALUATION OF TWO METHODS FOR SEPARATING HEAD RICE FROM BROKENS FOR HEAD RICE YIELD DETERMINATION B. J. Lloyd, A. G. Cnossen, T. J. Sieenmorgen ABSTRACT. Milled rice from lortory mill nd commercil scle mill ws evluted for hed rice yield using shker tle nd mchine vision system clled the GrinCheck. Comprisons were mde for oth medium nd long grin rice vrieties. For ech vriety, smples with different levels of roken kernels were nlyzed to determine the performnce of the two instruments over rnge of hed rice yields. Percentge hed rice ws lso mesured y the FGIS for commercilly milled smples to compre the shker tle nd the GrinCheck with n officil mesurement. Hed rice yield vlues were found significntly different etween the two instruments for ll of the lortory milled smples ut the men hed rice yield vrition ws equivlent for oth instruments. Commercilly milled rice showed tht the FGIS nd GrinCheck percentge whole kernel mesurements were equivlent while the shker tle verge ws seven percentge points less. Similr trends were found for oth vrieties. Keywords. Rice, Hed rice yield, Milling, Shker tle, GrinCheck. Hed rice yield (HRY) is one of the primry fctors tht currently determine the officil mrket grde of rice. Hed rice, or the whole" kernels in well milled rice smple, is defined y the USDA Federl Grin Inspection Service (1999) s, Unroken kernels of rice nd roken kernels of rice, which re t lest three fourths of n unroken kernel." HRY is the weight percentge of rough rice smple tht remins s hed rice fter complete milling. Hed rice is generlly worth twice s much s the roken kernel clsses of rewers, second heds, nd screenings. Thus, HRY primrily determines the economic vlue of rice since it is n indictor of the milling qulity of rice lot. End users of rice py premium prices for hed rice nd typiclly specify mximum tolernces of percentge roken kernels for ny given sle. Becuse of the importnce of HRY s n indictor of rice qulity, ccurte HRY mesurement y lortory milling tests is essentil. In ddition to its importnce in estlishing commercil economic vlue, HRY is lso used to quntify the effects of other processing opertions, such s drying, tempering, nd storge on milling qulity. Therefore, precise nd ccurte Article ws sumitted for review in My 2000; pproved for puliction y the Food nd Process Engineering Institute of ASAE in Mrch Pulished with the pprovl of the Director of the Agriculturl Experiment Sttion, University of Arknss. Mention of trdemrk or proprietry products does not constitute gurntee or wrrnty y the University of Arknss nd does not imply its pprovl to the exclusion of other products tht my lso e suitle. The uthors re Brin J. Lloyd, Grdute Student, Deprtment of Food Science, North Crolin Stte University, Rleigh, North Crolin, Auke G. Cnossen, Reserch Specilist, nd Terry J. Sieenmorgen, ASAE Memer Engineer, Professor, Food Science Deprtment, University of Arknss, Fyetteville, Arknss. Corresponding uthor: T. J. Sieenmorgen, 272 Young Ave., Fyetteville, AR 72704; phone: ; fx: ; e mil: tsieenm@comp.urk.edu. mesurement of HRY is importnt to producers, processors, nd end users of rice. Stndrds for test milling of rice re pulished y the USDA FGIS (1999). These stndrds specify the use of McGill No. 3 mill. Mny lortories hve opted for smller, more convenient mills. However, for most lortory methods, HRY determintion consists of three opertions: the lortory shelling of the rough rice smple, the lortory milling of the resulting rown rice, nd the seprtion of the hed rice from the roken kernels. The lortory milling opertion consists of milling n pproprite size smple of hulled rough rice in McGill No. 2 or No. 3 test mill, or other equivlent rice mill t pproprite predetermined mill settings. These mill settings include smple mount, mill weight plcement, nd milling durtion. Reid et l. (1998) nd Andrews et l. (1992) presented thorough evlutions of the mill settings for the McGill No. 2 rice mill. The test smple must e milled equl to degree of rn removl or etter thn the officil degree of well milled" rice for proper HRY mesurement (USDA FGIS, 1999). After milling, the next opertion of the HRY mesurement consists of ccurtely seprting hed rice from roken kernels. Typiclly, this procedure is done y mechnicl sizing method or y hnd picking. Both of these seprting methods re opertor dependent with opertor sujectivity ecoming fctor, especilly in hnd picking. Mechnicl seprting cn utilize sieves, riddles, nd indent cylinders. The most common lortory method used is device consisting of inclined indent pltes developed y Smith (1955). However, this device hs een shown to provide inccurte nd highly vrile seprtion of milled rice kernels s noted y Stermer nd Beerwinkle (1970). They compred 10 different sizers (lso clled shker tles) nd noted tht fctors such s stility of the supporting tle nd vritions in virtion of the crrige tle ffected sizer performnce. They concluded tht cceptle precision mong sizers ws otined y djusting virtion frequency Applied Engineering in Agriculture Vol. 17(5): Americn Society of Agriculturl Engineers ISSN

2 of the crrige tle using suitle vrile speed drive. The shker tle hs lso een noted s time consuming, requiring opertor supervision to ensure dequte seprtion. Previous reserchers used other devices to seprte the different frctions of long grin rice. Mthewson et l. (1990) uilt mechnicl system to seprte milled rice smple into four frctions using sieves. The system required 30 to 40 min to seprte 100 g of milled rice into frctions. They evluted their sieving system using n imge nlysis system, plcing five susets of 45 to kernels (or roken kernels) on lck velvet ckground. By cpturing the projected re of the kernels, ech piece ws ctegorized s whole kernels or rokens. Imge nlysis hs een used to successfully evlute nd/or seprte other grin commodities in fst nd effective mnner. Spirstein et l. (1987) used mchine vision system to clssify whole kernel smples of hrd red spring whet, rley, rye, nd ots sed on physicl fetures such s kernel length, width, nd re. Gunsekrn et l. (1988) used mchine vision system to evlute the qulity of corn nd soyens. Mjumdr et l. (1997) used n utomted mchine vision system to clssify kernels of Cnd Western red spring whet, Cnd Western Amer Durum whet, rley, ots nd rye. Tlsm et l. (1989) developed mchine vision system to clssify roken, whole, nd fissured rice kernels. They developed two imge processing techniques tht were reported to e 77 nd 92.4% effective compred to USDA inspected smples. Although the ove work ws importnt for imge processing of grins, most of the work ws done only with prototype systems. These systems hve not een commercilly mrketed or implemented in the grin industry or in grin inspection sttions due to slow opertionl speeds, cost, or other fctors. A new commercilly ville nlyticl instrument clled the GrinCheck" hs een designed to incorporte the non sujectivity of imge nlysis with recent dvnces in imge processing speed to evlute qulity of milled rice nd other grins. The GrinCheck uses CCD cmer, n imge processing system, nd mteril hndling system to utomticlly mesure HRY nd other importnt fctors in grding rice such s chlky kernels or foreign seeds. The GrinCheck is eing used y some rice processors to replce the shker tle for determintion of HRY or to mesure the percentge of whole kernels in milled rice smple. The purpose of this project ws to evlute the GrinCheck nlysis system versus the conventionl shker tle method in mesuring HRY for long grin nd medium grin milled rice smples. MATERIALS AND METHODS SEPARATION EQUIPMENT The shker tle used for this experiment ws Grinmn Model (Grin Mchinery Mfg. Corp., Mimi, Fl.). The originl single speed motor ws replced y vrile speed DC motor to llow djustment of the shker crrige virtion frequency for optimum seprtion of rokens from hed rice. Virtion frequency ws pproximtely Hz (0 cpm) with n mplitude of 3 mm. The screens used in the shker device were two No. 10 screens for seprtion of the medium grin vriety nd two No. 12 screens for the long grin vriety. The hole size in the screens ws 3.97 mm for the No. 10 screens nd 4.76 mm for the No. 12 screens. A GrinCheck model 310 system (Foss North Americ, Eden Pririe, Minn.) ws used to simultneously seprte hed rice from rokens nd mesure HRY. The GrinCheck system uses pre clirted Artificil Neurl Networks (ANN) softwre. The ANN softwre is trined to identify roken kernels using consensus of experts. Therefore, the decisions mde y the GrinCheck should e equivlent to the decisions mde e experienced inspectors. However, the vrince etween inspectors is eliminted when using the GrinCheck ecuse every GrinCheck instrument uses the sme softwre. A schemtic of the GrinCheck 310 is shown in figure 1. A 40 to g smple of milled rice ws loded into the mchine to feeder conveyor elt. The kernels were then utomticlly distriuted onto n nlysis conveyor elt moving in step wise mnner. The nlysis elt ws illuminted y fluorescent lmp encircling CCD cmer, which took sttic imge of severl kernels per frme s they pssed. The imge ws then digitized nd segmented to split the imge into individul kernels. The individul kernels were identified s either whole or roken y PC with the pre clirted ANN softwre. A pixel weight (g/pixel) ws determined y clculting the rtio of the totl smple mss s determined y n internl electronic lnce, over the totl numer of pixels using the sum of the projected re of ll the kernels present in the smple. The mss (nd percentge) of oth hed rice nd roken kernels ws internlly clculted y multiplying the totl numer of pixels of ech frction y the pixel weight. A windows sed disply softwre llowed user interfce for the UNIX control system of the GrinCheck. The computer displyed vrious outputs such s mss nd percentge of ech frction with n option to disply imges of ech kernel long with vrious other kernel dimensions. The hed rice percentge given y the GrinCheck ws multiplied y the smple s milled rice yield (sum of hed rice nd roken kernels) of the McGill No. 2 mill to otin HRY mesurement. This vlue then corresponded to the HRY mesurement from the shker tle method for equivlent comprison. Anlysis time for the GrinCheck ws pproximtely 5 to 7 min for smple size of 40 to g of milled rice. PROCEDURE FOR EXPERIMENT 1: LABORATORY MILLED SAMPLES Two rice vrieties were used, Cypress, long grin vriety, nd Bengl, medium grin vriety. Both vrieties were grown nd hrvested t the University of Arknss Rice Reserch nd Extension Center t Stuttgrt, Arknss. The moisture content t hrvest ws pproximtely 18 to 20% (unless otherwise stted; ll moisture content vlues re expressed on wet sis.). Both vrieties were dried using ir t C nd 17% reltive humidity for different durtions to produce three distinct levels of HRY noted s low, medium, nd high. Drying durtions were chosen tht would result in HRY levels round 55,, nd 65%, respectively. Detiled explntion of the drying procedures is found in Cnossen nd Sieenmorgen (2000) The finl equilirium moisture content of ll of the smples ws 12.5%, which is the typicl moisture content of rice for milling in the United Sttes. Six smples (1 g) of ech vriety nd drying condition comintions 644 APPLIED ENGINEERING IN AGRICULTURE

3 Figure. 1. Schemtic of the GrinCheck system. (36 smples totl) were then hulled in Stke lortory huller (model APS30 CXM, Stke, Houston, Tex.) to produce rown rice. Ech rown rice smple ws then milled in McGill No. 2 lortory rice mill (Rpsco, Brookshire, Tex.) for 30 s to produce well milled white rice smple comprised of hed rice nd roken kernels. The degree of milling (DOM) of the smples ws mesured with Stke MM 1B milling meter (Stke, Houston, Tex.) corresponding to DOM of 80 to 90. The white rice produced from the 1 g smples ws pproximtely 90 to 100 g. The entire milled rice smple ws loded onto the shker tle for seprtion nd only one person operted the shker tle for mesurement uniformity. As mentioned erlier, the GrinCheck required out one hlf of the milled rice smple. A Boerner divider ws used to split ech milled smple, nd then pproximtely 45 to 55 g ws loded into the GrinCheck for seprtion of hed rice nd rokens. The HRY of ech of the 36 milled rice smples ws determined y performing five mesurements with the shker tle method nd five mesurements using the GrinCheck imge nlyzer. The five replicte mesurements were verged nd the verge of the six replicte smples of ech drying condition nd seprtion method comintion re reported in figure 2 for Cypress nd figure 3 for Bengl. Anlysis of vrince ws performed for ll the dt using the GLM procedure in SAS (1998) for 3 fctor nested fctoril design for the 12 tretment comintions. PROCEDURE FOR EXPERIMENT 2: COMMERCIALLY MILLED SAMPLES A second experiment ws performed to compre the shker tle nd the GrinCheck s ility to seprte nd mesure the hed rice percentge for commercilly milled rice. The HRY could not e clculted ecuse the initil rough rice weight ws unknown. This experiment ws incorported into the study ecuse commercilly milled rice is generlly clener with less dust nd other smll prticulte mtter found in lortory test smple, due to efficient spirtion equipment found in commercil mills. An ccurte nd precise percentge hed rice mesurement is importnt to commercil rice millers in order to check milling nd grding process prmeters. Two medium grin nd two long grin milled rice of pproximtely 900 g ech were otined from Ricelnd Foods (Stuttgrt, Ark.) These smples contined vrying levels of hed rice nd rokens ecuse they hd originted from seprte, individul commercil rice lots with different post hrvest ckgrounds. These smples hd een commercilly spirted to remove most of the dust from the rn nd hulls. Ech of the four individul lots ws divided into six su smples nd ws mesured for percentge of hed rice with the shker tle nd the GrinCheck. After ll mesurements using the shker tle nd the GrinCheck Hed Rice Yield (%) Shker tle GrinCheck Shker tle GrinCheck Shker tle GrinCheck High rekge drying durtion (low HRY) Medium rekge drying durtion (medium HRY) Low rekge drying durtion (high HRY) Figure 2. Comprison of shker tle nd GrinCheck methods for seprtion nd determintion of HRY of Cypress long grin rice for three kernel rekge levels produced y three drying durtions. Ech HRY vlue represents the men of six smples mesured five times. Error rs represent two stndrd devitions of ech smple men. Vol. 17(5):

4 Hed Rice Yield (%) Shker tle GrinCheck Shker tle GrinCheck Shker tle GrinCheck High rekge drying durtion (low HRY) Medium rekge drying durtion (medium HRY) Low rekge drying durtion (high HRY) Figure 3. Comprison of shker tle nd GrinCheck methods for seprtion nd determintion of HRY of Bengl medium grin rice for three drying conditions incurring three kernel rekge levels. Ech HRY vlue represents the men of six smples mesured five times. Error rs represent two stndrd devitions of ech smple men. were mde, the su smples from ech of the four originl lots were recomined, then split gin into six su smples using Seeduro Boerner divider. These 24 su smples were then sent to the USDA FGIS grding sttion in Stuttgrt, Arknss, for officil hed rice percentge determintion y hnd picking. RESULTS AND DISCUSSION LABORATORY MILLED SAMPLES As seen in figure 2, HRY mesurements for long grin Cypress rice were significntly (α < 0.05) different within ech of the three HRY levels for the two seprtion methods. For ech of the three HRY levels, the HRYs mesured with the shker tle were lower thn those with the GrinCheck. These results indicted tht the shker tle nd the GrinCheck system produced different HRY mesurements for the sme long grin milled rice smples. One oservtion ws tht the shker tle often retined some hed rice wedged in the outer edges of the frmes of the indent screens, which ws consequently clssified s rokens. Tle 1 shows the stndrd devitions of ech of the men vlues for ech drying durtion, seprtion method, nd vriety. An ssocited F test for equivlence of stndrd devition showed tht none of the stndrd devitions were significntly different for ech drying durtion/seprtion Tle 1. P vlues for testing equivlence of the men HRY nd stndrd devitions for HRY mesurements of long nd medium grin lortory milled rice mesured y shker tle nd GrinCheck. Stndrd Devition of p Vlue for the Smple Men Drying Equivlence of Vriety Durtion Men HRY Shker Tle GrinCheck Cypress Low Cypress Medium Cypress High Bengl Low Bengl Medium [] Bengl High Pooled stndrd devition [] No significnt difference (α > 0.05) in men HRY. method tretment comintion. This result indicted tht oth the shker tle nd the GrinCheck hd equivlent mesurement vrition for the sme set of long grin l milled smples. Figure 3 gives the results for the medium grin Bengl rice. The HRY mesurements for ech seprtion method were significntly (α < 0.05) different for the low nd high drying durtion etween ech seprtion method. However for the medium drying durtion, HRY mesurements for the shker tle nd the GrinCheck were not significntly (α < 0.05) different. This occurrence ws the only cse when the GrinCheck nd the shker tle produced equivlent HRY mesurements for the l milled smples. While the GrinCheck system produced HRY mesurements close to the shker tle, the men HRY mesurements were consistently higher thn the shker tle (figs. 1 nd 2). Therefore sttisticl estimte of the ctul difference etween the men HRY of oth seprtion methods for ech drying durtion nd vriety ws tested for equivlence (SAS, 1998). Tle 2 gives these differences cross the drying durtions to determine if significnt equivlence occurred etween the sutrction of men HRY seprtion methods cross the drying durtions. For oth Cypress nd Bengl, the estimted differences in seprtion methods t high HRY level nd low HRY level were significntly different. This finding showed tht the GrinCheck gve higher HRY vlue, ut the difference ws not constnt cross these HRY levels. Compring the low nd medium HRY levels, oth vrieties hd high p vlues of nd indicting tht the differences in these cses were equivlent. Finlly, when compring the medium nd high HRY levels, n equivlent difference existed for Cypress. These comprisons illustrted tht simple proportionlity constnt sutrcted from the GrinCheck s HRY mesurement to mtch the shker tle would need to e specific for ech HRY level nd ech vriety. A pooled smple vrince ws clculted for oth seprtion methods for oth vrieties nd drying conditions. The reported stndrd devitions of the pooled dt re presented in tle 1. Like the individul stndrd devitions, these pooled devitions were not significntly different Tle 2. Comprison of the difference in men HRY for two seprtion methods (shker tle nd GrinCheck) for lortory milled rice. [] Difference in HRY Vriety Seprtion Method nd Smple Tretment HRY etween ech Mesurement Method Cypress Shker High HRY Foss High HRY Shker Medium HRY Foss Medium HRY Shker Low HRY c Foss Low HRY Bengl Shker High HRY c Foss High HRY Shker Medium HRY Foss Medium HRY Shker Low HRY c Foss Low HRY [] Within ech vriety, like letters indicte tht there ws no significnt difference (α > 0.05) in the differences etween seprtion methods. 646 APPLIED ENGINEERING IN AGRICULTURE

5 etween the GrinCheck nd the shker tle. This comprison showed tht for lortory milled smples, oth methods hd equl vrition cross rnge of HRY levels for lortory milled long nd medium grin rice. COMMERCIALLY MILLED SAMPLES Figure 4 shows the results for the commercilly milled long grin rice lots. For lot no. 1, which hd the highest percentge of roken kernels, ll three seprtion methods produced significntly different percentges of hed rice. The shker tle nd FGIS mesurements differed y more thn 7 percentge points. This difference could result in high HRY discrepncies for such wide mrgin in percentge hed rice. Comprison of the stndrd devitions of lot no. 1 for ech method (tle 3) reveled tht the GrinCheck nd FGIS vrition were not significntly different. However, the shker tle hd stndrd devition tht ws pproximtely three times lrger thn those y the other two methods. For lot no. 2, the GrinCheck nd FGIS men hed rice vlues were not significntly different. This result could e explined y the fct tht the GrinCheck ws clirted using smples with high percentge of hed rice (>80% hed rice) from the FGIS. Thus, equivlent mesurements were nticipted nd usully oserved for the smples of the commercilly milled lots with higher hed rice percentges. The shker tle hed rice men ws pproximtely 7 percentge points less thn the FGIS. When compring stndrd devitions for lot no. 2, no significnt difference ws found mong the three methods. The higher shker tle stndrd devition ws ttriuted to n incresed likelihood of ech method identifying nd removing the rokens ecuse there ws smller popultion of roken kernels. A fewer numer of roken kernels would llow the shker tle screens to cpture more of them ecuse less indents would e filled. Figure 5 shows lmost identicl results for medium grin commercilly milled rice s those found for the long grin rice. For the low HRY smple (lot no. 3), ech method produced significntly different hed rice men vlue. Agin, the shker tle men ws pproximtely 7 percentge points lower thn the FGIS vlue. The stndrd devitions for the three methods were not significntly % Hed Rice Lot # c Shker tle GrinCheck FGIS Shker tle GrinCheck FGIS Lot #2 Figure 4. Comprison of the shker tle, GrinCheck, nd FGIS methods for determintion of percentge hed rice in two long grin rice lots milled in commercil milling system. Dt represents the men of six mesurements with error rs representing two stndrd devitions. Like letters indicte tht the men hed rice mesurements within lot were not significntly different. Tle 3. Stndrd devitions for percentge hed rice of long nd medium grin commercilly milled rice s mesured y the shker tle, the GrinCheck, nd the FGIS. Stndrd Devition of the Smple Men [] Vriety Lot No. Shker Tle GrinCheck FGIS Long grin Long grin Medium grin Medium grin Pooled stndrd devition [] Like letters cross mesurement methods indicte significnt difference (α > 0.05) did not occur. different for lot no. 3. For the higher hed rice lot no. 4, the GrinCheck nd the FGIS hed rice mens were not significntly different. The shker tle gin produced the lowest hed rice percentge vlue. The stndrd devition ws not significntly different for the GrinCheck nd the FGIS methods. The shker tle, however, hd stndrd devition over five times lrger thn those y the other two methods. It ws speculted tht the higher shker tle vrition could e prtilly ttriuted to slight mislignment of the indent screens when they were secured to the shker tle crrige tle fter they were tken off to remove the rokens. This prolem would cuse the kernels to migrte to one side of the indent plte minimizing the effect of the indent holes to retin the roken kernels. A pooled vrince for ech method ws lso clculted from the entire commercilly milled dt set using ll four lots. These pooled vrinces gve n indiction of the mesurement error for ech method over the rnge of ll commercilly milled rice lots used in this study. Tle 3 shows the mgnitude of the pooled stndrd devitions. The shker tle hd pooled stndrd devition pproximtely twice s lrge s the FGIS method. The GrinCheck hd pooled stndrd devition not significntly different thn tht y the FGIS method indicting tht the GrinCheck s overll mesurement vrince for two vrieties t two hed rice levels ws nering tht of hnd picking y experienced FGIS personnel. % Hed Rice Lot # c Lot # Shker tle GrinCheck FGIS Shker tle GrinCheck FGIS Figure 5. Comprison of the shker tle, GrinCheck, nd FGIS methods for determintion of percentge hed rice in two medium grin white rice lots milled in commercil milling system. Dt represents the men of six mesurements with error rs representing two stndrd devitions. Like letters indicte tht men hed rice mesurements within lot re not significntly different. Vol. 17(5):

6 The GrinCheck system performed etter with fewer clenings required etween smples for the commercilly milled rice thn tht of l milled rice. A 5 min clening procedure ws necessry pproximtely every 10 smples for the l milled rice. This clening lod ws lessened with the commercilly milled smples. These smples hd less rn dust nd other foreign mteril tht could lter pttern recognition s well s cot the cmer lens with excessive dust, cusing possile devitions. CONCLUSIONS Hed rice yield for lortory milled long nd medium grin rice ws mesured for smples otined from three drying conditions using shker tle nd GrinCheck system. HRY vlues were significntly different etween methods for ll three HRY levels nd oth vrieties. The GrinCheck mesured slightly higher HRYs in every cse, nd the differences in seprtion methods were equivlent for only few HRY level nd vriety comintions. The vrition in men HRY ws equivlent for oth the shker tle nd the GrinCheck for ll tretment comintions for the lortory milled smples. Commercilly milled rice smples lso proved tht the shker tle nd the GrinCheck provided significntly different HRY mesurements. At low hed rice levels, the shker tle, the GrinCheck, nd officil hnd picking y the FGIS provided significntly different hed rice percentge determintions for oth long nd medium grin rice. At higher hed rice levels, the shker tle gve mesurement of percentge hed rice out 7 percentge points lower thn the other two methods. The GrinCheck nd FGIS vlues were not significntly different for the high hed rice smples for long or medium grin milled rice. The GrinCheck proved to e n effective instrument in mesuring percentge hed rice for milled rice, especilly for clen, commercilly milled smples. For these smples, the GrinCheck mesured equivlent hed rice percentges to the FGIS ut higher thn the conventionl shker tle hed rice percentge mesurements. REFERENCES Andrews, S. B., T. J. Sieenmorgen, nd A. Muromoustkos Evlution of the McGill No. 2 rice miller. Cerel Chemistry 69(1): Cnossen, A. G., nd T. J. Sieenmorgen The glss trnsition temperture concept in rice drying nd tempering: effect on milling qulity. Trnsctions of the ASAE 43(6): Evers, G. W., J. P. Crigmiles, nd R. H. Brown Clirtion of the indent plte rice sizer. PR 3104, Rice Reserch in Texs, Texs Agriculturl Experiment Sttion, PR Gunsekrn, S., T. M. Cooper, nd A. G. Berlge Evluting qulity fctors of corn nd soyens using computer vision system. Trnsctions of the ASAE 31(4): Mjumdr, S., D. S. Jys, nd N. R. Bulley Clssifiction of cerel grins using mchine vision. ASAE Pper No St Joseph, Mich.: ASAE. Mthewson, P. R., I. Zys, nd R. Rousser A simple mechnicl device for mrket clssifiction of milled rice. Cerel Foods World 35(2): Reid, J. D., T. J. Sieenmorgen, nd A. Muromoustkos Fctors ffecting the slope of hed rice yield vs. degree of milling. Cerel Chemistry 75(5): Spirstein, H. D., M. Neumn, E. H. Wright, E. Swedyk, nd W. Bushuk An instrumentl system for cerel grin clssifiction using digitl imge nlysis. J. of Cerel Sci. 6(1): SAS Institute Inc User s guide for the SAS system, version Cry, N.C.: SAS Institute Inc. Smith, W. D The determintion of the estimte of hed rice nd totl yield with the use of the sizing device. The Rice Journl Nov.: 9. Stermer, R. A., nd K. R. Beerwinkle Clirtion of the indent plte rice sizer. The Texs Agriculturl Experiment Sttion Progress Reports. PR Tlsm, S., P. devisser, nd E. Dekker A crck detector for milled rice. ASAE Pper No St. Joseph, Mich.: ASAE. USDA, Federl Grin Inspection Service (FGIS) Code of Federl Regultions for Grin Inspection, Pckers, nd Stockyrd Administrtion. Code of Federl Regultions. 7 (Ch. VIII): prts ACKNOWLEDGEMENTS We wish to thnk the University of Arknss Rice Processing Progrm Industry Allince Group for contriuting finncilly to this project. In ddition to their sponsorship to this Progrm, we wish to cknowledge Foss North Americ for providing equipment for this project. 648 APPLIED ENGINEERING IN AGRICULTURE