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1 As. J. Food Ag-Ind. 2010, 3(04), Asin Journl of Food nd Agro-Industry ISSN Avilble online t Reserch Article Functionl properties of sesme protein concentrtes from sesme mel Eksit Onsrd*, Ptchneepun Pomsmud nd Poonpun Audtum Deprtment of Agro-Industry, Fculty of Agriculture, Ubonrtchthni University, Wrinchumrp, Ubon Thilnd. *Author to whom correspondence should be ddressed, emil: e.onsrd@gmil.com Abstrct Three sesme protein concentrtes were prepred from deftted sesme flour (DSF) by two different methods; (i) slt solution nd isoelectric precipittion (SPC-slt) nd (ii) lkli solution ph 9 or ph 11 nd isoelectric precipittion (SPC-pH 9 nd SPC-pH 11). Protein recovery nd chemicl composition of sesme protein concentrtes were determined nd some of their functionl properties were investigted in comprison with soy protein isolte (SPI). The protein recoveries in SPC-slt, SPC-pH 9 nd SPC-pH 11 bsed on Kjeldhl procedure were 19.5%, 21.9% nd 35.3%, respectively. Protein contents of SPC-pH 9 (82.9%) nd 11 (83.3%) ws higher thn those of SPC-slt (75.5%). The minimum protein solubility of ll SPC smples ws found t ph 5. All SPC smples were more soluble thn SPI t ph 3, 8 nd 9. Emulsion ctivity index (EAI) of ll SPC smples ws superior to those of SPI, while emulsion stbility index (ESI) of ll SPC smples ws inferior to those of SPI. Wter holding cpcity, ft bsorption cpcity nd foming properties of SPC smples were lower thn those of SPI Keywords: deftted sesme flour, isoelectric precipittion, soy protein isolte, chemicl composition, solubility, EAI, ESI, Thilnd Introduction Sesme (Sesmum indicum L.) is n importnt oilseed which is cultivted in mny tropicl countries. In 2007, the Thi Office of Agriculturl Economics reported tht pproximte sesme production nd frm vlue in Thilnd were 43,000 tons nd 1,030 million bht, respectively [1]. Aside from being n importnt source of edible oil, sesme seed is n essentil ingredient for trditionl Asin food nd desserts. Sesme seed is composed of bout % oil, % protein nd % sh [2, 3] In the sesme oil industry, sesme seed is commonly used s the rw mteril for oil extrction, either using orgnic solvents or by mechnicl pressing. The sesme mel is by-product fter oil extrction. It is usully fed to nimls s protein source. The mel is good source of nutrition,

2 As. J. Food Ag-Ind. 2010, 3(04), contining pproximtely 50% protein [4]. This mel hs high potentil for use s protein source or s n ingredient in the food industry. Sesme protein isoltes or concentrtes normlly re prepred by isoelectric precipittion nd slt precipittion [3, 4, 5, 6]. If sesme protein ingredient is going to find widespred ppliction s n ingredient in the food industry, it is importnt to know its functionl properties, for exmple solubility, wter holding cpcity, ft bsorption cpcity, emulsifying properties nd foming properties. Few studies hve been done on the functionl properties of sesme proteins from deftted sesme mel [3, 4, 5, 6]. Therefore, the objective of this the study ws to exmine some functionl properties of sesme protein concentrtes in comprison with soy protein isolte. Mterils nd Methods Mterils Sesme mel used s source of sesme protein throughout this reserch ws obtined from the Lerning Orgniztion nd Development Centre of Sesme for Sustinble Agro-Household Industry, Fculty of Agriculture, Ubonrtchtni University, Thilnd. Soy protein isolte (SPI) ws obtined from Thi Food (Thilnd) Ltd. The powdered SPI hd composition of 81.4% protein, 0.1% ft, 5.0% moisture, 2.2% sh, 0.8% fibre nd 11.2% crbohydrte. All generl chemicls used in this study were of nlyticl grde. Methods Preprtion of deftted sesme flour Deftted sesme flour (DSF) ws prepred following the method of Inyng nd Iduh [4]. Sesme mel ws vcuum-dried (Binder, VD115, Germny) t 50 0 C for 1 h nd then finely sieved through n electric grter. The sesme mel ws deftted with hexne t rtio of 1:4 (w/v) under constnt shking (Innov, New Brunswick Scientific, USA) t 220g for 1 h. The hexne ws chnged three times nd then decnted nd removed in forced-ir oven t 60 o C for 1 h. The DSF obtined hd finl ft content of < 2%. The DSF ws ground to pss through 75 mesh nd kept in vcuum continers t 4 o C prior to use. Preprtion of sesme protein concentrtes Two different methods for sesme protein concentrte (SPC) were studied to estblish the processing conditions for the mximum seprtion of the protein from DSF. Alkli solution nd isoelectric precipittion SPC ws prepred ccording to the method developed by Gndhi nd Srivstv [3], with some modifictions. DSF ws mixed with wter t rtio of 1:10 (w/v). The ph of the suspended sesme mel ws djusted to ph vlues rnging from 7 to 12 using 2.0 M NOH, continuously stirred with mgnetic stirrer for 1 h nd centrifuged t 2,822g for 15 min. The soluble phses were djusted to ph 4.5 using 0.1 or 1.0 M HCl which led to the precipittion of protein. The suspensions were centrifuged t 2,822g for 15 min, fter which the superntnt ws poured wy nd the precipittes were weighed nd ssyed for protein content by the Kjeldhl method. The precipittes were neutrlized to ph 7.0 using 0.1 or 1.0 M NOH, dilyzed by distilled wter overnight t 4 o C nd then freeze-dried. The sesme protein concentrte by lkli solution nd isoelectric precipittion ws clled SPC-pH. Slt solution nd isoelectric precipittion SPC ws prepred ccording to the procedure of Rivs, et l. [5] with some modifictions. DSF ws suspended in 0.0 to 5.0 M NCl t rtio of 1:10 (w/v) t ph 7. The suspended sesme mel ws stirred with mgnetic stirrer for 1 h nd then centrifuged t 2,822g for 15 min to seprte solution phses. The soluble phses were djusted to ph 4.5 using 0.1 or 1.0 M HCl which led to the precipittion of protein. The suspensions were centrifuged t 2,822g for 15 min

3 As. J. Food Ag-Ind. 2010, 3(04), fter which the precipittes were collected nd nlyzed for protein content by the Kjeldhl method. The precipittes were neutrlized to ph 7.0 using 0.1 or 1.0 M NOH, dilyzed by distilled wter overnight t 4 o C nd then freeze-dried. The sesme protein concentrte by slt solution nd isoelectric precipittion ws clled SPC-slt. Protein recovery nd chemicl composition nlysis The chemicl composition of sesme mel, DSF nd SPC were determined ccording to AOAC stndrd methods [7]. The crbohydrte content ws estimted by subtrcting the sum of percentge of moisture, crude ft, crude protein nd sh contents from 100%. The protein recovery ws clculted s follows; Protein recovery (%) = weight (g) of SPC X protein content (%) of SPC X 100 (1) weight (g) of DSF X protein content (%) of DSF Determintion of some functionl properties Protein solubility (PS) SPC solutions (2% w/v) were prepred with dispersing powdered protein into distilled wter djusted to ph 3 to 9. The protein solutions were stirred with mgnetic stirrer t 4 0 C overnight, centrifuged t 2,822g for 30 min. The protein smple ws directly solubilized by 0.5 M NOH for determintion of totl protein. The protein content of the superntnts ws determined by the Biuret method [8] using bovine serum lbumin (BSA) s protein stndrd. Protein solubility ws clculted s: PS (%) = 100 x P S /P T, where P S is the protein content in the superntnt fter centrifugtion nd filtrtion, nd P T is the totl protein content present in the protein smple. Wter holding cpcity (WHC) nd Ft bsorption cpcity (FAC) WHC nd FAC of SPC were determined by the method of Gndhi nd Srivstv [3]. One grm of the smple ws mixed with 10 ml distilled wter or soyben oil in centrifuge tubes nd then llowed to stnd for 30 min. Smples were centrifuged t 2,822g for 30 min. The superntnt ws discrded nd the tube ws weighed. WHC (grms of wter per grm of smple) ws clculted using the eqution; WHC = (W 2 -W 1 )/W 0 (2) where W 0 ws the weight of the dry smple (g), W 1 ws the weight of the tube plus dry smple (g) nd W 2 ws the weight of the tube plus sediment (g). FAC (grms of oil per grm of protein) ws clculted using the eqution; FAC = (F 2 -F 1 )/ F 0 (3) where F 0 ws the weight of the dry smple (g), F 1 ws the weight of the tube plus dry smple (g) nd F 2 ws the weight of the tube plus sediment (g). Emulsifying properties Emulsifying ctivity index (EAI) nd emulsion stbility index (ESI) of SPF were mesured by the method of Lopez, et l. [9]. SPC (4 g) were suspended in distilled wter (100 ml). The protein solution ws stirred with mgnetic stirrer for 30 min nd then centrifuged t 2,822g for 30 min. The superntnt ws collected nd determined by the Biuret method [7] using bovine serum lbumin (BSA) s the protein stndrd. To prepre the emulsion, 60 ml of protein solution nd 20 ml of soyben oil were homogenized t high speed for 1 min by homogenizer (Robot Doupe MP450C, USA). The emulsion ws then diluted 200 fold with 0.1% (w/v) SDS,

4 As. J. Food Ag-Ind. 2010, 3(04), contining 0.1 mol/l sodium chloride t ph 7.0. The bsorbnce of the diluted emulsion ws then mesured t 500 nm in 1 cm pth length cuvette t 0 min (A 0 ) nd 10 min (A 10 ) fter preprtion using spectrophotometer (HACK DR4000, USA). EAI nd ESI were clculted s follows: EAI (m 2 g -1 ) = (2 x x A 0 x N)/(C x φ) (4) ESI (min) = (A 0 x 10)/(A 0 -A 10 ) where N represents dilution fctor; φ is the oil phse volume (φ of soyben oil = 0.25) nd C is the concentrtion of protein (mg/ml). Foming properties Foming cpcity nd foming stbility were determined by the method of Khlid, et l. [10]. Three grms of SPC nd one hundred ml of distilled wter t ph 7 were homogenized t high speed for 5 min by homogenizer (Robot Doupe, MP450C, USA) nd then trnsferred to mesuring cylinder. The volume of fom t 30 s ws clculted nd the volume increse expressed s percent fom cpcity. The fom stbility mesured the decrese in volume of fom s function of time up to period of 90 min. Sttisticl nlysis Triplictes of dt were used for the nlysis. The obtined dt were nlyzed using one wy nlysis of vrince (ANOVA). Mens were compred by Duncn multiple rnge test (DMRT) with men squre error t 5% probbility (SPSS 11.5 for Windows sttisticl softwre). Results nd Discussion Chemicl composition nd protein recovery of sesme protein concentrtes (SPC) The chemicl compositions of sesme mel, DSF, sesme protein concentrte (SPC) by lkli solution nd isoelectric precipittion (SPC-pH) nd sesme protein concentrte by slt solution nd isoelectric precipittion (SPC-slt) re shown in Tbles 1 nd 2. Extrction of oil from sesme mel led to incresed chemicl compositions of DSF. The protein content in DSF incresed, which ws 41.2% higher thn in sesme mel. Similr results were reported by Inyng nd Iduh [4], who found tht protein content incresed from 24.1% in dehulled sesme seed to 59.7% sesme flour. The high protein content in DSF could be considered s potentil source tht could be used in protein concentrtes. Tble 1. Proximte composition (%) of sesme mel nd deftted sesme flour (DSF). Constituents Sesme mel DSF Moisture 7.92 ± ± 0.03 Ft ± ± 0.12 Protein b ± ± 0.96 Fiber 6.22 ± ± 0.63 Ash 5.27 ± ± 0.88 Crbohydrte c ± ± 0.52 vlues re from three repliction b 6.25 ws used s the nitrogen conversion fctor c Estimted by difference The recovery of proteins in SPC-slt nd SPC-pH re presented in Figures 1 nd 2. For SPC-slt, the protein recovery incresed s the concentrtion of NCl incresed to 2.0 M nd then decresed s the concentrtion of NCl incresed from 2.0 to 5.0 M (Figure 1). This is becuse of the slting-in process. The slt ions interct with oppositely chrged groups, which in turn

5 As. J. Food Ag-Ind. 2010, 3(04), decreses electrosttic ttrction between protein molecules nd cuses the proteins to become more solvent [11]. The highest protein recovery ws found t 2.0 M NCl (20%), while the lowest protein recovery ws found t 0.0 M NCl (0.5%). Beyond 2 M NCl, recovery of the protein decresed (slting-out). This slting-out effect results from the competition between the protein nd the slt ions for the wter molecules necessry for their respective solvency. At high slt concentrtions, there re not enough wter molecules vilble for protein solvency, since the mjority of the wter molecules re strongly bound to the slts. Thus, protein-protein interctions become more powerful thn protein-wter interctions. This my led to reduced solubility [12]. 50 Protein recovery (%) g f b c d e NCl (Molr) Figure 1. Protein recovery of sesme protein concentrtes by slt extrction t 0-5 M NCl nd isoelectric precipitte. DMRT (p<0.05) vlues re presented s br. Columns with different letters re significntly different (p<0.05). For SPC-pH, the protein recovery rnged from % (Figure 2). The protein recovery of SPC-pH incresed when the ph incresed from 7 to 12. The highest protein recovery ws found t ph 11 (35.3%), while the lowest protein recovery ws found t ph 7 (7.1%). This my be becuse the solubility nd extrctbility t n lkline ph cn be enhnced by incresing the net electricl chrge of the protein. After slt nd lkline extrction proteins, the proteins were precipitted t their isoelectric point (ph 4.5). The percentges of the protein recovered fter precipittion t the SPC-slt relted to solubility of the protein. The 2 M NCl concentrtion ws chosen for the extrction of protein from DSF, while ph 9 nd 11 were chosen for the extrction of protein from DSF. The protein recovery in 2 M NCl extrction (SPC-slt) (20%) ws lower thn those in ph 9 (SPC-pH 9) (21.9%) nd ph 11 (SPC-pH 11) (35.3%). These results indicted tht lkli solution nd isoelectric precipittion ppered more effective thn slt solution nd isoelectric precipittion.

6 As. J. Food Ag-Ind. 2010, 3(04), Protein recovery (%) e d c b ph Figure 2. Protein recovery of sesme protein concentrtes by lkli extrction t ph 7-12 nd isoelectric precipitte. DMRT (p<0.05) vlues re presented s br. Columns with different letters re significntly different (p<0.05). The chemicl composition of SPC-slt, SPC-pH 9 nd SPC-pH 11 re shown in Tble 2. The SPC-pH 9 nd 11 hd higher protein content (82.9 nd 83.3%) thn those of SPC-slt (75.5%). This result indicted tht differences in preprtion process ffect proximte compositions of protein content. SPC contined high mount of protein, which ws slightly higher thn tht reported by Inyng nd Iduh [4] (70.7%). Tble 2. Proximte composition (%) of sesme protein concentrtes by lkli extrction t ph 9 nd ph 11 (SPC-pH 9 nd SPC- ph 11) nd slt extrction (SPC-slt). Constituents SPC-pH9 SPC-pH11 SPC-slt Moisture 5.65 ± ± ± 1.56 Ft 1.32 ± ± ± 0.05 Protein b ± ± ± 1.62 Fiber 1.05 ± ± ± 0.13 Ash 1.78 ± ± ± 0.10 Crbohydrte c 8.32 ± ± ± 1.56 vlues re from three repliction b 6.25 ws used s the nitrogen conversion fctor c Estimted by difference Functionl properties of sesme protein concentrtes Protein solubility The protein solubility of SPC-slt, SPC-pH 9 nd SPC-pH 11 ws determined in comprison with soy protein isolte (SPI) (Figure 3). The ph-solubility profiles were similr for ll proteins, with the solubility hving U-shped curve. The minimum protein solubility of SPC-slt, SPCpH 9, SPC-pH 11 nd SPI ws observed t ph 5 (2.6% for SPC-slt, 1.6% for SPC-pH 9, 1.2% for SPC-pH 11 nd 10.3% for SPI), which is close to the isoelectric points (pi) of sesme protein isolte [6, 10]. The profiles showed tht the protein solubility of SPC-slt, SPC-pH 9, SPC-pH 11 nd SPI incresed when the ph ws ltered either below or bove the pi. At ph bove vlue

7 As. J. Food Ag-Ind. 2010, 3(04), of 3 nd below vlues 8-9 pi, ll the SPCs exhibited higher solubility thn those of SPI. This result ws in greement with the work reported by Lopez, et l. [9]. The reltively low protein solubility ner their pi vlues cn be ttributed to the fct of hving low net chrge, so tht there is little electrosttic repulsion between them. In ddition, there my even be n electrosttic ttrction between positively chrged ptches on one protein molecule nd negtively chrged ptches on nother. At ph vlues bove or below the pi, the protein hs net negtive or positive chrge, nd so there is strong electrosttic repulsion nd ionic hydrtion forces between the protein molecules, which prevents them from ggregting nd leds to greter protein solubility [11]. These differences in solubility could hve been due to differences in the type of proteins present, the intrinsic solubility chrcteristics of these proteins, the denturtion sttes of the proteins nd the presence of ny impurities tht could ffect solubility (such s minerls or polr lipids). Protein Solubiliy (%) SPC-pH9 SPC-pH11 SPC-slt SPI ph Figure 3. Protein solubility of sesme protein concentrtes by lkli extrction t ph 9 nd ph 11 (SPC-pH9 nd SPC-pH11) nd slt extrction (SPC-slt) in comprison with soy protein isolte (SPI) s relted to ph rnge of 3 to 8 in distilled wter. Wter holding cpcity (WHC) nd ft bsorption cpcity (FAC) Wter holding cpcity (WHC) nd ft bsorption cpcity (FAC) of SPC-slt, SPC-pH 9 nd SPC-pH 11 were studied in comprison with soy protein isolte (SPI) (Tble 3). The WHC of SPC-pH 9 (2.0 g of wter/g of protein), SPC-pH 11 (3.5 g of wter/g of protein) nd SPC-slt (2.3 g of wter/g of protein) were significntly (p< 0.05) lower thn those of SPI (6.1 g of wter/g of protein), but similr to those reported by Khlid, et l. [10] (2.1 ml of wter/g of protein) nd Gndhi nd Srivstv [3] (1.9 ml of wter/g protein). When the WHC of SPC ws compred to other proteins, SPC showed similr vlues with the WHC of buckwhet protein (3.3 g wter/g protein), rice brn protein concentrte of Bsmti 370 rice (3.9 g wter/g protein), but ws lower thn soy protein isolte (7.3 g wter/g protein) [13, 14]. Aletor, et l. [15] reported tht WHC vlues rnging from 1.49 to 4.72 (g/g) re considered criticl in viscous food such s soups nd grvies. It indictes tht SPCs possess good wter bsorption cpcity nd cn be used in products requiring high wter retention.

8 As. J. Food Ag-Ind. 2010, 3(04), Tble 3. Wter holding cpcity (WHC), ft bsorption cpcity (FAC) of sesme protein concentrtes by lkli extrction t ph 9 nd ph 11 (SPC-pH 9 nd SPC-pH 11) nd slt extrction (SPC-slt) in comprison with soy protein isolte (SPI). Smple Wter holding cpcity 1 (g of wter /g of protein) Ft bsorption cpcity 1 (g of oil /g of protein) Emulsion ctivity index (EAI) 1 (m 2 /g) Emulsion stbility 1 (min) SPC- ph ± 0.07 c 1.19 ± 0.10 c ± 0.93 c ± 3.84 d SPC-pH ± 0.36 b 2.69 ± ± ± 1.19 b SPC-slt 2.32 ± 0.25 c 2.03 ± 0.19 b ± 7.34 b ± 2.35 c SPI 6.06 ± ± ± 0.43 c ± Vlues re given s men ± SD from triplicte determintion -d In column, men vlue followed by the sme superscript re not significntly different t p>0.05 (DMRT) Ft bsorption cpcity (FAC) of SPC-slt, SPC-pH 9, SPC-pH 11 nd soy protein isolte (SPI) re presented in Tble 3. SPC-pH 11 (2.7 g of oil/g of protein) hd significntly (p< 0.05) higher FAC thn SPC-slt (2.0 g of oil/g of protein) nd SPC-pH 9 (1.2 g of oil/g of protein), but ws similr to SPI (2.9 g of oil/g of protein). FAC of sesme protein concentrtes (SPC) from the study were lso similr to tht reported by Khlid, et l. [10] (1.5 ml oil / g protein). FAC of SPC ws higher thn csein (0.9 g oil/g protein) nd ws similr to buckwhet protein (2.9 g oil/g protein) nd soy protein isolte (2.6 g oil/g protein) [13]. FAC is ttributed to the physicl entrpment of oil nd to the number of nonpolr side chins on proteins tht bind hydrocrbon chins on the ftty cids [16]. The difference between FAC of different proteins could be relted to the vrition in mino cid compositions nd severl prmeters such s hydrophobicity, degree of denturtion nd the size nd flexibility of the protein. Emulsifying properties The emulsifying properties of SPC-slt, SPC-pH 9 nd SPC-pH 11 were evluted in comprison with tht of soy protein isolte (SPI). The emulsifying ctivity index (EAI) of SPCpH 11 ws significntly higher (p < 0.05) thn those of SPC-slt, SPC-pH 9 nd SPI (Tble 3). SPC-pH 11 exhibited n increse in EAI s the extrction ph 11 ws better thn ph 9 nd slt. This result indicted tht differences in extrction methods nd conditions ffect emulsifying properties of sesme proteins. All SPCs were lso better in EAI thn SPI. Previous reports hve shown tht sesme protein isolte exhibited superior emulsifying properties to soy protein isolte [9, 6]. Normlly, EAI is mesure of the bility of the protein to id the dispersion of the oil phse nd to quickly provide sufficient coting of the interfcil re to void immedite colescence [17]. Emulsion stbility is property very often evluted in reltion to time nd is relted to the droplet size, wherein the smller the size the greter the stbility. The emulsion stbility index (ESI) of SPC-pH 11 (44.4 min) exhibited higher indices thn those of SPC-slt (37.9 min) nd SPC-pH 9 (31.5 min), but were lower thn those of SPI (63.6 min) (Tble 3). These results suggest tht while the SPI my not form n emulsion redily, the stbility of the emulsion fter its formtion is reltively higher. Stbility of the protein film formed t the interfce of the emulsion is dependent on the interctions of the proteins in oil nd queous phses [18]. Besides, the vrious fctors, including ph, droplet size, net chrge, interfcil tension, viscosity nd protein conformtion, could ffect the vlues of ES [19].

9 As. J. Food Ag-Ind. 2010, 3(04), Foming properties The foming properties (foming cpcity nd foming stbility) of SPC-slt, SPC-pH 9 nd SPC-pH 11 were compred with SPI (Figures 4 nd 5). SPC-slt exhibited higher foming cpcity nd stbility thn SPC-pH 9 nd ph 11. When compred with SPI, foming cpcity nd stbility of ll SPCs were lower thn those of SPI. Bsiclly, the function of fom is relted to the rte of decrese of surfce tension of the ir/wter interfce cused by bsorption of protein molecules [20]. Grhm nd Phillips [21] linked good fombility with flexible protein molecules, which reduces surfce tension. Low fombility on the other hnd cn be relted to highly ordered globulr proteins, which resist surfce denturtion. The bsic requirements of proteins s good foming gents re the bility to (i) dsorb rpidly t ir-wter interfce during bubbling, (ii) undergo rpid conformtionl chnge nd rerrngement t the interfce nd (iii) form cohesive viscoelstic film vi intermoleculr interctions. The first two fctors re essentil for better fombility wheres the third is importnt for the stbility of the fom. The foming properties of proteins re influenced by sources of protein, methods nd therml prmeters of processing, including protein isoltion, temperture, ph, protein concentrtion, mixing time, method of foming [20]. Foming Cpcity (%) c d b 0 SPC-pH 9 SPC-pH 11 SPC-slt SPI Figure 4. Foming cpcity of sesme protein concentrtes by lkli extrction t ph 9 nd ph 11 (SPC-pH9 nd SPC-pH11) nd slt extrction (SPC-slt) in comprison with soy protein isolte (SPI). DMRT (p<0.05) vlues re presented s br. Columns with different letters re significntly different (p<0.05).

10 As. J. Food Ag-Ind. 2010, 3(04), Foming Stbility (min) d c b 0 SPC-pH 9 SPC-pH 11 SPC-slt SPI Figure 5. Foming stbility of sesme protein concentrtes by lkli extrction t ph 9 nd ph 11 (SPC-pH9 nd SPC-pH11) nd slt extrction (SPC-slt) in comprison with soy protein isolte (SPI). DMRT (p<0.05) vlues re presented s br. Columns with different letters re significntly different (p<0.05). Conclusions Sesme protein concentrtes re good sources of protein ( %). The study of sesme protein concentrtes shows tht solubility nd EAI of the sesme protein concentrtes were higher thn those of soy protein isolte, while ESI, foming properties, WHC nd FAC of sesme protein concentrtes were lower thn those of soy protein isolte. Therefore, these proteins my be used s food ingredient to substitute for SPI, where solubility nd emulsifying properties re needed. Acknowledgments This reserch ws supported by the Division of Reserch Promotion nd Fculty of Agriculture, Ubonrtchthni University, Thilnd. The uthors would like to thnk the Lerning Orgniztion nd Development Centre of Sesme for Sustinble Agro-Household Industry nd Thi Foods (Thilnd) Ltd. for providing the mteril used in this study nd lso thnk Prof. Michel Hre nd Dr. Pryong Udomworprnt for editing the mnuscript. References 1. Office of Agriculturl Economics. (2008). Agriculturl Sttistics of Thilnd Bngkok, Ministry of Agriculture nd Co-opertives. 2. Elleuch, M., Besbes, S., Roiseux, O., Blecker, C. nd Atti, H. (2007). Qulity chrcteristics of sesme seeds nd by-products. Food Chemistry, 103 (2),

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