Effects of transglutminase on the quality of white salted noodles made from Korean wheat cultivars

Transcription

1 Interntionl Food Reserch Journl 21(1): (2014) Journl homepge: Effects of trnsglutminse on the qulity of white slted noodles mde from Koren whet cultivrs 1 Kng, C. S., 1 Kim, K. H., 1 Choi, I. D, 1 Son, J. H. nd 2* Prk, C. S. 1 Ntionl Institute of Crop Science, RDA, Iksn , Kore, 2 Deprtment of Crop Science nd Biotechnology, Chonbuk Ntionl University, Jeonju , Kore Article history Received: 17 June 2013 Received in revised form: 14 August 2013 Accepted: 15 August 2013 Keywords White slted noodles Trnsglutminse Whet Noodle qulity Abstrct The objectives of this study ws to investigte the influences of incresing levels of trnsglutminse (TG) on dough rheologicl properties nd the chrcteristics of white slted noodles regrding two Koren whet cultivrs, cvs. Keumkng nd Younbek, nd commercil whet flour for noodle mking (Com), nd to evlute qulity of white slted noodles from 13 Koren whet flours with the 0.4% TG tretment. In Keumkng, Younbek nd Com, wet gluten, mixing time nd mixing tolernce incresed s the ddition of TG incresed from 0.2 to 0.6%, compred to those of whet flours with no TG tretment. No significnt differences in SDS-sedimenttion volume nd wter bsorption for the mixogrph of flours ws found in the ddition of TG. of the noodle dough sheet incresed s the ddition of TG incresed, lthough wter bsorption, thickness of the noodle dough sheet nd cooking loss did not chnge with incresed TG tretments. White slted noodles with 0.4% of TG tretment showed greter elsticity nd hrder texture of cooked noodles thn those of no TG tretment. There were no consistent differences in the texture of cooked noodles from between 0.4 nd 0.6% TG tretment. In noodle chrcteristics with 0.4% TG tretment of 13 Koren whet cultivrs, developed fter 2000, lightness of noodle dough sheet nd hrdness of cooked noodles with 0.4% TG tretment (81.50 nd 3.80 N, respectively) were higher thn tht of no tretment of TG (80.83 nd 3.51 N, respectively) t P < No significnt effects of TG tretment were found in other chrcteristics. All Rights Reserved Introduction Trnsglutminse (TG: protein-glutmine γ-glutmyl trnsferse, EC ) ctlyzes the formtion of nondisulfide covlent cross-linking between ε-mino group on peptide-bound glutminyl residues nd β-crboxymide group on proteinbound glutmine residues in the protein frctions (Motoki nd Seguro, 1998; Kurishi et l., 2001). TG my produce beneficil effects in the rheologicl nd bking properties of the flour through the formtion of lrge insoluble polymers in dough, which its effect is comprble to chemicl oxidizing improvers (Motoki nd Seguro, 1998; Kurishi et l., 2001). TG hs been proved to be potentil enhncer of bking properties becuse very smll dosge cn cuse obvious ltertions on dough properties compred to chemicl oxidizing improvers (Tseng nd Li, 2002). TG hs modified the viscoelsticity of whet flour dough, which incresed mixing time, mixing tolernce, nd decresed wter bsorption, extensibility nd stickiness (Gerrrd et l., 1998; Tseng nd Li, 2002; Bsmn et l., 2002; Buer et l., 2003; Rosell et l., 2003; Seo et l., 2003; Bonet et l., 2006; Cbllero et l., 2007). TG tretment in bred doughs produced significnt improvement of bred volume, nd texture nd grin of crumb (Gerrrd et l., 1998; Gerrrd et l., 2000; Bsmn et l., 2002; Buer et l., 2003; Cbllero et l., 2007). In ddition to the effect regrding yest-rised bred products, TG tretment lso prevented the depression of sponge cke fter bking nd improved lof volume of puff pstry nd croissnts (Gerrrd et l., 2000). TG is utilized widely in the production of noodles nd pst in Jpn becuse TG tretment improves texture in noodles/pst mnufcturing (Kurishi et l., 2001). TG tretment ws beneficil to void breking the dried noodles during pcking nd shipping (Shiu nd Chng, 2013). Cooking loss ws reduced by TG tretment becuse strches in noodle dough re better held in the gluten network nd reduced solid loss into the boiling wter, which the surfce of noodles is less sticky nd reducing bulkiness, nd then the cooking yield of noodles lso is improved (Kurishi et l., 2001). TG tretment of noodles including instnt noodles nd pst prevented deteriortion of texture fter cooking nd incresed hrdness nd elsticity nd decresed stickiness of cooked noodles (Skmoto et l., 1996; Gn et l., 2009; Choy et l., 2010; Shiu nd Chng, 2013). *Corresponding uthor. Emil: pcs89@jbnu.c.kr Tel:

2 196 Kng et l./ifrj 21(1): It is expected tht the cross-linkings introduced by TG re het-stble nd reduced leching of strchy mterils onto the noodles (Wu nd Corke, 2005). White slted noodles re populr in Kore nd qulity improvement of whet for mking noodles with desirble processing qulity nd texturl properties of cooked noodles is receiving incresed ttention by whet breeders in Kore (Prk et l., 2006). Enhncement of noodle mking processing nd the texture of cooked noodles from Koren whet hve been very importnt in incresing consumption of Koren whet products. However, most Koren whet cultivrs nd dvnced lines hve showed inferior noodle color to commercil noodle whet flours s well s lower lof volume nd hrder crumb firmness thn commercil bred flours in spite of the similr protein content (Prk et l., 2006). Dough stbility nd texture of cooked noodles s well s sensory chrcteristics could be improved by the ddition of TG to Koren whet cultivr, cv. Geuru (Seo et l., 2003). The benefit treted with TG in noodles mde from Koren whet flours could be preferble to both mnufcturers nd consumers. Therefore, this study ws conducted to investigte the influences of incresing levels of TG on dough rheologicl properties nd the chrcteristics of white slted noodles of two Koren whet flours compred to commercil noodle flour, nd to evlute the qulity of white slted noodles from 13 Koren whet cultivrs, which developed fter 2000, through the optimum TG tretment in order to provide useful informtion for improving whet qulity for mking noodles in whet breeding progrms nd expnding the utiliztion of Koren whet flours. Mterils nd Methods Mterils Two Koren whet cultivrs, cvs. Keumkng nd Younbek, were obtined from the Ntionl Institute of Crop Science (Suwon, Kore). Commercil flour for mking white slted noodles ws kindly provided by Smyng Milmx (Chenn, Kore). These whet flours were used to determine the effect of TG on dough rheologicl properties nd the qulity of white slted noodles through the vrious TG tretments. ACTIVA STG-M which is designed for the improvement of pst nd noodle texture with n ctivity of 28 U/g, ccording to the mnufcture s dt, ws obtined from Ajinomoto Co., Inc. (Tokyo, Jpn). TG ws dded t three levels (0.2, 0.4 nd 0.6%) bsed on the flour weight bsis (14% mb) nd whet flour without TG ws used for the control. Thirteen Koren whet cultivrs were used to evlute dough rheologicl properties nd the qulity of white slted noodles with n optimum mount of TG tretment (4 g/kg whet flour, 14% mb). Grins of these cultivrs were obtined from the Ntionl Institute of Crop Science (Suwon, Kore). Two kilogrms of whet were conditioned overnight to rech 15% moisture content nd then milled with feed rte of 100 g/min nd with roll settings of 8 nd 5 in brek rolls nd 4 nd 2 in reduction rolls. Whet ws milled to bout 60% extrction on Bühler experimentl mill ccording to the AACCI Approved Method (AACC I, 2010). Anlyticl methods Moisture, protein nd sh contents of whet flour were determined ccording to AACCI Approved Methods , nd , respectively (AACC I, 2010). Amylose content of prime strch ws determined by the iodometric method described by Morrison nd Lignelet (1983). Dmged strch content ws determined by the procedure described by Gibson et l. (1992), using n enzymtic ssy kit (MegZyme Pty., Austrli). of flour ws mesured by Minolt CM-2002 (Minolt Cmer Co., Jpn) with n 11 mm mesurement perture. Prticle size distribution of flour ws mesured by the multi-wvelength lser prticle size nlyzer LS13320MW (Beckmn Coulter, Inc. USA). A SDS sedimenttion test ws performed ccording to the procedure of Axford et l. (1979) with modifiction in flour weight to 3 g. Wet gluten content ws evluted with Glutomtic keeping the volume of Glutomtic wsh solution t 4.8 ml for ll smples, ccording to the AACCI Approved Method (Morrison nd Lignelet, 1983). Wter bsorption nd mixing properties of flours were determined using 10 g mixogrph (Ntionl Mfg. Co., Lincoln, NE), ccording to AACCI Approved Method (AACC I, 2010). Preprtion of white slted noodles White slted noodles were prepred with optimum wter bsorption of noodle dough ccording to the procedure of Prk et l. (2003). Commercil whet flour for noodle mking, which requires 34% bsorption to produce uniform, smooth nd nonsticky dough, ws used s reference for comprison to other flours during the determintion of optimum wter bsorption for noodle mking. (100 g, 14% moisture bsis) ws mixed with predetermined mount of sodium chloride solution in pin mixer (Ntionl Mfg. Co., USA) for 4 min t hed speed of 86 rpm. The concentrtion of sodium chloride solution used for mking noodles with different

3 Kng et l./ifrj 21(1): bsorptions ws djusted to produce 2.0% result in the noodle dough. Dough ws pssed through the rollers of noodle mchine (Ohtke Noodle Mchine Mfg. Co., Jpn) t 65 rpm with 3 mm gp; dough ws folded nd pressed between the sheeting rollers. The folding nd sheeting were repeted twice. The dough sheet ws rested for 1 hr nd then subjected to three dditionl presses t progressively decresing gps of 2.40, 1.85 nd 1.30 mm. After the finl pressing, the thickness of the dough sheet ws immeditely mesured by micrometer dil thickness guge (Pecock Dil Thickness Guge G, Ozki Mfg. Co., Jpn). A piece of noodle sheet ws plced in plstic bgs for determintion of color. of the dough sheet ws mesured by Minolt CM (Minolt Cmer Co., Jpn) with n 11 mm mesurement perture. The rest of the dough sheet ws cut with no. 12 cutting rollers into noodle strnds of bout 30 cm in length with 0.3 x 0.2 cm cross section. Cooking loss nd texturl properties of cooked noodles Rw noodles (20 g) were cooked for 18 min in boiling distilled wter (500 ml) nd then rinsed with cold wter. Two replictes of cooked noodles were evluted by texture profile nlysis (TPA) using TA-XT2 Texture Anlyzer (Stble Micro Systems, Englnd) within 5 min fter cooking. A set of five strnds of cooked noodles ws plced prllel on flt metl plte nd compressed crosswise twice to 70% of their originl height using mm metl blde t speed of 1.0 mm/sec. From force-time curves of the TPA, hrdness, springiness nd cohesiveness were determined ccording to the description of Prk et l. (2003). TPA of cooked noodles ws lso determined fter soking in 70 C wter for 10 min to determine the chnges of texture during serving of cooked noodles. Cooking loss ws determined by the modifiction of Wu nd Corke (2005). Rw noodles (20 g) were cooked for 18 min in boiling wter (200 ml) then rinsed with distilled wter gently for 1 min then drined for 30 s. All the wter (bout 1000 ml) ws plced in tred beker (W1, g) evported using hot-plte to pproximtely 50 ml nd then dried t 45 C to constnt weight (W2, g). The moisture content of the white slted noodles ws determined (W3, g). The cooking loss ws clculted s: Cooking loss = [(W2 W1) / (20 W3) kg kg 1 ] 100 Sttisticl nlysis All tests were run t lest in triplicte in completely rndomized design. Sttisticl nlysis of dt ws performed by SAS softwre (SAS Institute, Cry, NC) using Duncn s multiple rnge test. Differences were considered significnt t P < Results nd Discussion Properties of whet flour nd dough Four chrcteristics of two Koren whet cultivrs nd commercil noodle flour re summrized in Tble 1. Keumkng, hrd white winter whet, is leding whet cultivrs in Kore nd is generlly used for yellow lkline noodles, nd Younbek is suitble for mking white slted noodles. Protein content of Keumkng ws higher (12.84%) thn tht of Younbek (9.93%) nd commercil noodle flour (10.20%). Commercil noodle flour showed lower sh nd mylose content (0.41 nd 24.21%, respectively) nd higher dmged strch content (6.59%) thn Koren whet cultivrs (0.47%, > 26.69% nd < 6.06%, respectively). Commercil noodle flour showed higher lightness vlue (91.75) thn Koren whet cultivrs (< 89.96). Commercil flours for mking white slted noodles re null in the Wx-B1 llele of grnule bound strch synthse, which is probbly responsible for the soft texture of cooked noodles, long with 10% protein content of whet flour (Hou, 2001). Commercil noodle flours hd higher dmged strch content thn US whet cultivrs with similr protein content nd qulity (Prk et l., 2003). SDS-sedimenttion volume, wet gluten content nd mixogrph properties of whet flour with different TG content re summrized in Tble 2. SDS-sedimenttion nd wet gluten content of Keumkng (51.00 ml nd 28.80%, respectively) were higher thn those of Younbek (30.33 ml nd 20.65%, respectively) nd commercil noodle flour (29.00 ml nd 23.90%, respectively). Commercil noodle flour showed higher wet gluten content thn Younbek, lthough these whet flours hd similr protein content nd SDS-sedimenttion volume. Commercil noodle flours could be mixtures of soft nd hrd whet flours, becuse their composition of high moleculr weight glutenin subunit (HMW-GS) contined both nd t Glu-D1 loci, nd nd t Glu-B1, nd their score of HMW- GS ws higher thn club nd soft whet cultivrs (Prk et l., 2003). Wet gluten content slightly incresed s the ddition of TG incresed, wheres there were

4 198 Kng et l./ifrj 21(1): Tble 1. chrcteristics of two Koren whet flours nd commercil whet flour for noodles Ash Protein Amylose Dmged strch Keumkng 0.47±0.00 b 12.84± ± ±0.20c 89.96±0.10b Younbek 0.47± ±0.11b 26.69± ±0.04b 88.98±0.01c Com 0.41±0.00b 10.20±0.02b 24.21±0.27b 6.59± ±0.05 Com = commercil whet flours for mking white slted noodles. b Vlues followed by the sme letters re not significntly different t P < Tble 2. Effect of trnsglutminse on SDS-sedimenttion volume, wet gluten content nd mixogrph properties from two Koren whet flours nd commercil whet flour for noodles Mixogrph Trnsglutminse b SDS sedimenttion Wet gluten Wter bs orption Mixing time Mixing tolernce (ml) (min) (mm) Keumkng ±1.00 c 28.80±0.20c 63.17± ±0.06b 19.33±1.15bc ± ±0.10b 63.50± ±0.12b 20.00±1.73b ± ±0.25b 63.83± ±0.06b 19.67±1.53b ± ± ± ± ±1.00 Younbek ±0.58b 20.65±0.05g 59.50±0.50b 3.57±0.06ef 20.33±0.58b ±1.00b 21.30±0.10f 60.00±0.00b 3.67±0.06de 20.00±1.00b ±0.76b 21.25±0.25f 59.83±0.29b 3.73±0.06cd 19.67±0.58b ±1.15b 21.20±0.30f 59.83±0.29b 3.73±0.12cd 20.00±1.00b Com ±0.00b 23.90±0.00e 59.50±0.50b 3.43±0.12fg 17.33±0.58d ±0.29b 24.45±0.58e 59.67±0.58b 3.40±0.00g 17.67±1.15cd ±0.50b 24.75±0.05d 59.83±0.76b 3.40±0.17g 17.00±1.00c ±0.58b 24.75±0.05d 60.00±1.00b 3.83±0.06c 19.33±0.58bc Com = commercil whet flours for mking white slted noodles. b Trnsglutminse (28U/g) ddition ws 2, 4, 6g/kg in whet flour, respectively. c Vlues followed by the sme letters re not significntly different t P < no consistent differences in SDS-sedimenttion volume mong flours with different mounts of TG in whet flour. TG could be ttributed the compounded bonded to gluten during wet extrction of gluten from whet flour, which is in greement with the previous reports (Rosell et l., 2003; Bonet et l., 2006). The mount of wet gluten incresed with the ddition 1% of TG (100 Unit/g), while higher levels (1.5% nd 2.0%) hd decresed wet gluten content (Rosell et l., 2003). Gluten index vlues fter the ddition of TG lso incresed in previous results (Rosell et l., 2003; Bonet et l., 2006), but the gluten index did not evluted in this study. Wter bsorption nd mixing time of the mixogrph of Keumkng (63.17% nd 4.03 min, respectively) ws higher thn those of Younbek nd commercil noodle flour (59.50% nd < 3.57 min, respectively). The mixing tolernce of commercil noodle flour (17.33 mm) ws lower thn tht of Keumkng (19.33 mm) nd Younbek (20.33 mm). In the mixogrph properties of whet flours with TG tretments, the ddition of TG did not influence on the wter bsorption of the mixogrph. Keumkng with the ddition 0.6% of TG showed longer mixing time nd mixing tolernce of the mixogrph (4.67 min nd mm, respectively) compred to the ddition of lower levels (< 4.13 m in nd < mm, respectively). Mixing time of the mixogrph of commercil noodle flour with the ddition 0.6% of TG (3.83 min) ws higher thn tht of other TG tretments (3.40 min). However, mixing time of the mixogrph ws not influenced by the ddition of TG in Younbek nd the ddition of TG did not ffect the mixing tolernce of the mixogrph of Younbek nd commercil noodle flour. Gerrd et l. (1998) reported tht the structurl chnge of gluten due to the TG cross-linkge incresed wter holding cpcity nd TG hd profound influence on the decrese of wter bsorption for dough. The effects of TG tretment on the rheologicl properties of dough were different depending on dose nd cultivr chrcteristics (Bsmn et l., 2002; Buer et l., 2003; Lrre et l., 2000; Autio et l., 2005). Kho nd Ng (2008) reported tht the ddition of TG (2000 ppm with 0.1 U/mg of ctivity) did not obviously ffect the mixing properties of soft nd hrd whet flours. They lso proposed tht the mixing time might hve been insufficient to show the effect of TG with low level (2,000 ppm) on the dough properties in the mixogrm becuse the rection of TG in wetted flour tkes time (Kho nd Ng, 2008). Buer et l. (2003) lso reported tht there ws no difference in the mixing properties of dough in frinogrm with the ddition of lower level of TG (13.5 ppm, 9.9 U/mg) but did observe significnt differences with high level of TG (> 45.0 ppm, 9.9 U/mg). Seo et l. (2003) reported tht the ddition of TG (3,000-7,000 ppm, 17.13U/g) hd no impct on physicl properties in dough mde with the imported whet flour (mixed whet flour Austrlin stndrd white nd Austrlin hrd), while significnt chnge in dough stbility nd vlorimeter vlue is observed in dough prepred Koren whet flour, cv. Geuru. However, the ddition of TG (10,000 ppm) in Geuru decresed dough stbility (Seo et l., 2003). Dough development time nd stbility vlues initilly incresed with incresing levels of TG with very low levels (< 0.5%), but decresed t higher TG levels (Bsmn et l., 2002). TG ctivity ws 28 U/g nd levels were from 0.2 to 0.6% in this study, which TG ctivity ws lower but levels were similr to previous reports (Bsmn et l., 2002; Buer et l., 2003; Seo et l., 2003; Kho nd Ng, 2008). Wter bsorption did not chnge by the ddition of TG nd only Keumkng with the ddition 0.6% of TG showed higher mixing time nd mixing tolernce of the mixogrph thn other tretments. Chrcteristics of noodle dough nd texture of cooked noodles Chrcteristics of the noodle dough sheet, cooking loss nd texture of cooked noodles prepred with different TG content re summrized in Tble 3. Optimum wter bsorption of Keumkng nd Younbek ws 32 nd 34%, respectively. TG decresed wter bsorption of noodle dough only t the 1% level, consistently with previous results in white slted noodles (Wu nd Corke, 2005). However, the differences in optimum wter bsorption of noodle dough with the ddition % of TG

5 Kng et l./ifrj 21(1): Tble 3. Effect of trnsglutminse on the chrcteristics of noodle dough sheet, cooking loss nd texture of cooked noodles from two Koren whet flours nd commercil whet flour for noodles Noodle Dough Sheet Cooking loss Texture of Cooked Noodles TG b d Abs c Thickness HD SP CO AD (mm) (N) (Rtio) (Rtio) (N mm) Keumkng b e 1.85± ±0.42h 5.56±0.18b 4.85±0.03c 0.92±0.00cd 0.63±0.01e -0.06± b 1.86± ±0.02g 5.41±0.11bc 4.91±0.06c 0.93±0.01bc 0.66±0.01c -0.07±0.01b b 1.86± ±0.22e 5.59±0.14b 5.13±0.01b 0.93±0.01bc 0.65±0.01cd -0.06± b 1.84±0.03b 83.52±0.31f 5.39±0.04bc 5.53± ±0.01cd 0.62±0.01f -0.07±0.00b Younbek ±0.00de 80.39±0.16h 5.51±0.10bc 3.90±0.02f 0.91±0.00d 0.63±0.00e -0.07±0.00b ±0.03cde 85.15±0.09de 5.78± ±0.03ef 0.92±0.01cd 0.63±0.01e -0.07±0.02b ±0.04e 85.69±0.31d 5.59±0.12b 4.23±0.04d 0.94± ±0.00de -0.07±0.01b ±0.02e 86.73±0.00bc 5.56±0.17b 4.32±0.03d 0.93±0.01bc 0.63±0.00e -0.07±0.01b Com ±0.05bcde 84.83±1.48e 5.27±0.18c 3.73±0.05g 0.92±0.01cd 0.69±0.00b -0.07±0.01b ±0.03bcd 87.50±0.09b 5.51±0.04bc 3.91±0.07f 0.93±0.00bc 0.69±0.00b -0.07±0.01b ±0.02bcde 88.07± ±0.07bc 4.05±0.12ef 0.94± ± ±0.00b ±0.02bc 86.53±0.15c 5.43±0.04bc 4.19±0.12de 0.94± ±0.00b -0.08±0.02b Com = commercil whet flours for mking white slted noodles. b Trnsglutminse (28U/g) ddition ws 2, 4, 6g/kg in whet flour, respectively. c Abs = optimum wter bsorption of noodle dough sheets. d HD = hrdness, SP = springiness, CO = cohessiveness, AD = dhessiveness. e Vlues followed by the sme letters re not significntly different t P < Tble 4. chrcteristics of 13 Koren whet cultivrs developed fter 2000 Developed Ash Protein Amylose Dmged strch SDS sedimenttion Wet gluten Yer (ml) Anbek ± ±0.02i 25.61±0.63e 5.84±0.13b 20.00±0.00k 91.79±0.13f 13.80±0.20g Bekjoong ±0.00b 8.39±0.04j 26.72±0.16bcd 4.74±0.19e 22.00±1.00j 92.21±0.10e 13.55±0.35g Djoong ±0.01d 10.13±0.00f 27.39±0.04b 4.83±0.16e 34.00±0.00f 92.48±0.15cd 21.50±0.50c Goso ±0.01c 10.12±0.03f 27.50± ±0.23cd 30.50±1.50h 93.35± ±0.00cd Hnbek ± ±0.07d 26.01±0.00cde 7.50± ±0.00c 91.77±0.06f 21.00±0.40cd Jeokjoong ±0.00c 8.27±0.02k 26.80±0.00bc 4.71±0.09e 36.00±0.00e 92.66±0.07c 13.35±0.95g Jo ±0.00d 9.90±0.05g 26.68±0.51bcd 2.78±0.20f 12.00±0.00l 93.46± ±0.80e Joeun ±0.01c 12.00± ±0.43f 5.48±0.31bc 34.00±0.00f 91.70±0.15f 15.75±0.45f Jokyung ±0.00b 9.49±0.01h 26.95±0.00b 5.44±0.13bc 32.00±0.00g 92.51±0.01cd 16.60±0.30f Jonong ±0.01c 10.89±0.00e 25.61±0.24e 3.07±0.41f 29.00±0.00i 92.93±0.15b 23.60±0.40b Jopoom ±0.01d 11.42±0.00b 27.07±0.28b 4.98±0.28de 42.50± ±0.09d 21.35±0.85c Sun ±0.01d 11.29±0.03c 26.48±1.34bcde 4.98±0.15de 39.50±0.50b 92.15±0.16e 20.05±0.05d Sukng ±0.01c 11.96± ±0.35de 5.49±0.23bc 37.00±0.00d 91.69±0.00f 26.35±1.35 Vlues followed by the sme letters re not significntly different t P < were not found in this study. Thickness of noodle dough from Keumkng (1.85 mm) ws higher thn tht of Younbek (1.77 mm) nd commercil noodle flour (1.80 mm). Thickness of the noodle dough sheet of white slted noodles from Koren whet flours positively correlted with protein content rther thn protein qulity properties (Prk et l., 2006). However, thickness of noodle dough did not chnge by the ddition of TG. Resting time of the noodle dough sheet could not be enough to gluten development treted with the TG mount in this study, like s the rection of TG in wetted flour tkes time in dough development of the mixogrph (Kho nd Ng, 2008). Commercil noodle flour showed higher lightness vlue (84.83) thn Koren whet flours (< 80.60). Protein content of whet flour lso hs negtive reltionship with lightness of the noodle dough sheet in white slted noodles (Oh et l., 1985). of noodle dough from ll whet flours incresed with s the ddition of TG. Wu nd Corke (2005) reported tht lightness of dried white slted noodles incresed with over 1.0% of TG (24 U/g ctivity). Brightness of instnt noodles with 0.5% of TG tretment ws higher thn tht of 1.0% of TG tretment becuse ft bsorption in the mking of instnt fried noodles ws reduced by tretment with TG (Choy et l., 2010). However, the color of lkline noodles with soy protein isoltes ws dversely ffected by TG tretments, which relted to the dense structure of noodle dough nd then produced deteriortion in the color of the noodle (Gn et l., 2009). Commercil noodle flour (5.27%) showed lower cooking loss thn Koren whet flour (> 5.51%). Cooking loss did not chnge with incresed TG tretments, lthough Younbek with the ddition 0.2% of TG ws higher (5.78%) thn without TG tretment (5.51%). Wu nd Corke (2005) concluded tht TG did not significntly influence the cooking loss of dried white slted noodles with the % of TG tretments. The cooking loss of TG treted dried noodles incresed s compred to tht of without TG tretment (Shiu nd Chng, 2013). Commercil noodle flour showed lower hrdness nd higher cohesiveness (3.73 N nd 0.69, respectively) of cooked noodles thn Koren whet flours (> 3.90 N nd 0.63, respectively). Springiness nd dhesiveness of commercil noodle flour (0.92 nd N mm) were similr to those of Koren whet flours (0.92 nd N mm for Keumkng nd 0.91 nd N mm for Younbek, respectively). Hrdness of cooked noodles positively correlted with protein content in previous reports (Prk et l., 2003; Oh et l., 1985). Commercil flour for noodle mking contined low mylse content, due to the null chrcteristics in the Wx-B1 llele of grnule bound strch synthse, showed lower hrdness of cooked noodles compred to flours with similr protein content (Prk et l., 2003). As strch mylose content decresed, hrdness of cooked noodles decresed nd cohesiveness incresed in prtil wxy whet flours (Bik et l., 2003). Hrdness of cooked

6 200 Kng et l./ifrj 21(1): Tble 5. Chrcteristics of noodle dough sheet from 13 Koren whet flours with different tretment of trnsglutminse Absorption Without Trnsglutminse Thickness (mm) Noodle Dough Sheet 0.4% Trnsglutminse Thickness (mm) Anbek ±0.01c 78.91±1.09g 1.70±0.01f 79.66±0.60fg Bekjoong ±0.01c 82.71±0.69b 1.72±0.01ef 83.18±0.41b Djoong 34.00b 1.71±0.02c 77.22±0.79h 1.71±0.02ef 77.75±1.08h Goso 34.00b 1.71±0.02c 80.52±0.06ef 1.72±0.02ef 81.31±0.24de Hnbek 33.00c 1.89± ±0.92b 1.89± ±0.64b Jeokjoong ±0.03c 82.27±0.24bc 1.71±0.01ef 83.31±0.61b Jo 34.00b 1.79±0.01b 84.28± ±0.02b 84.51±0.51 Joeun 33.00c 1.78±0.02b 80.83±0.51de 1.76±0.02c 82.30±0.43c Jokyung 34.00b 1.78±0.03b 80.81±0.30de 1.77±0.01c 81.71±0.51cde Jonong 34.00b 1.73±0.01c 79.93±0.38f 1.74±0.01de 81.05±0.21e Jopoom 33.00c 1.77±0.02b 80.53±0.53ef 1.81±0.02b 80.02±0.73f Sun 33.00c 1.73±0.01c 81.62±0.96cd 1.72±0.02ef 81.95±0.64cd Sukng 33.00c 1.77±0.01b 78.65±0.65g 1.76±0.01cd 79.00±0.58g Vlues followed by the sme letters re not significntly different t P < Tble 6. Texture of cooked noodles from 13 Koren whet flours with different tretment of trnsglutminse Texture of Cooked Noodles Without Trnsglutminse 0.4% Trnsglutminse Hrdness Springiness Cohesiveness Hrdness Springiness Cohesiveness (N) (Rtio) (Rtio) (N) (Rtio) (Rtio) Anbek 3.07±0.13e 0.91±0.01bc 0.64±0.00bc 3.21±0.12f 0.90±0.01cd 0.64±0.00de Bekjoong 2.45±0.11f 0.90±0.00bc 0.65± ±0.21f 0.90±0.01d 0.64±0.01e Djoong 3.27±0.06d 0.92±0.01b 0.66± ±0.15e 0.92±0.02bc 0.64±0.01cde Goso 3.55±0.07c 0.92± ± ±0.12b 0.91±0.01cd 0.65±0.01b Hnbek 3.76±0.04b 0.91±0.01b 0.65± ±0.07d 0.91±0.02bcd 0.66±0.02b Jeokjoong 3.08±0.06e 0.90±0.01bc 0.65±0.01bc 3.52±0.10e 0.90±0.02cd 0.65±0.01bc Jo 3.57±0.11c 0.90±0.02c 0.65±0.01bc 3.85±0.16d 0.91±0.02bcd 0.65±0.01bc Joeun 4.07± ± ± ±0.10b 0.93± ±0.01 Jokyung 3.21±0.06d 0.91±0.02bc 0.65± ±0.07e 0.91±0.01bcd 0.65±0.00bcd Jonong 4.15± ±0.01bc 0.64±0.01c 4.11±0.04c 0.90±0.01cd 0.65±0.01bc Jopoom 3.30±0.12d 0.92±0.02b 0.65±0.01bc 3.59±0.05e 0.92±0.01bc 0.64±0.01cde Sun 4.05± ± ±0.01b 4.43± ±0.01b 0.65±0.01bcd Sukng 4.14± ±0.02b 0.64±0.00bc 4.31±0.07b 0.92±0.01b 0.64±0.00cde Vlues followed by the sme letters re not significntly different t P < noodles incresed s the ddition of TG incresed in ll three whet flours. Springiness of cooked noodles from Younbek nd commercil noodle flour with the ddition over 0.4% of TG incresed compred to tht of other whet flours, lthough there ws no significnt difference in Keumkng. Cohesiveness of Keumkng nd commercil noodle flours incresed with the ddition 0.4% of TG nd then leveled off in 0.6% of TG tretment. No significnt differences were found in cohesiveness of Younbek. Adhesiveness of cooked noodles ws not influenced by TG tretments in ll three whet flours. The dhesiveness of cooked dried white noodles ws not ffected by TG tretment (Shiu nd Chng, 2013). Seo et l. (2003) proposed tht texturl properties of cooked noodles s well s sensory chrcteristics could be improved by the ddition of 3,000-7,000 ppm (17.13 U/g ctivity) to Koren whet flour, cv. Geuru. Shiu nd Chng (2013) proposed tht dried or cooked white noodles with good qulity cn be produced by incubting with % (25U/g) TG tretment for 30 min t 30 C. White slted noodles with 0.4% of TG tretment could improve the lightness of the noodle dough sheet nd elstic texture of cooked noodles, lthough hrdness of cooked noodles incresed in this study. Noodle chrcteristics with 0.4% of TG tretment chrcteristics of 13 Koren whet cultivrs, developed fter 2000, were summrized in Tble 4. The verge of sh, protein, mylose, dmged strch content, lightness of flour, SDS-sedimenttion volume nd wet gluten were 0.45%, 10.29%, 26.31%, 5.02%, Figure 1. The differences in lightness of noodle dough sheet (A) nd hrdness of cooked noodles (B) between no TG tretment nd 0.4% of TG tretment in 13 Koren whet cultivrs. Error brs indicte the stndrd error 92.39, ml nd 18.93%, respectively. Ash, protein nd mylose content were %, % nd %, respectively. Dmged strch, lightness of flour, SDS-sedimenttion volume nd wet gluten were %, , % nd %, respectively. Protein content positively correlted with wet gluten nd dmged strch correlted with lightness of flours nd sh content, which greed with previous reports (Prk et l., 2003; Prk et l., 2006). Chrcteristics of the noodle dough sheet from 13 Koren whet flours with different tretment of trnsglutminse were summrized in Tble 5. In the noodle dough sheet with no TG tretment, the verge of optimum wter bsorption, thickness nd lightness of the noodle dough sheet with no TG tretment were 33.85%, 1.76 mm nd 80.84, respectively. Thickness of the noodle dough sheet with 0.4% TG tretment (1.76 mm) ws the sme s tht of no tretment of TG. of noodle doughs with 0.4% TG tretment (81.50) ws higher thn tht of no tretment of TG (80.83) t P < 0.05 (Figure. 1-A), lthough Wu nd Corke (2005) proposed the difference in color ppernce ws not visully detectble s the chnge in lightness ws less thn 2 units. Higher lightness of noodles with 0.4% TG tretment compred to no TG tretment ws the sme result in Tble 3. These results indicte tht lightness of the noodle dough sheet could be improved with 0.4% TG tretment in Koren whet cultivrs. Texture of cooked noodles from 13 Koren whet flours with different tretment of trnsglutminse were summrized in Tble 6. Hrdness of cooked noodles with 0.4% TG tretment ws higher (3.83

7 Kng et l./ifrj 21(1): N) thn tht of no TG tretment (3.51 N, Figure. 1-B), which 3.83 N is comprble to hrdness of Com without TG tretment (Tble 3). Increse of hrdness for cooked noodles with 0.4% TG tretment ws lso found in Tble 3. TG tretment could increse hrdness of cooked noodles in Koren whet cultivrs. TG incresed the hrdness of dried white slted noodles (Wu nd Corke, 2005). The increse in hrdness with TG tretment ws relted to stronger nd tighter protein network between the strch grnules which ws responsible for limiting excessive wter uptke during cooking (Kovács et l., 2004). Springiness nd cohesiveness of cooked noodles with 0.4% TG tretment ws higher thn those of no TG tretment in Younbek nd Com (Tble 3). However, neither springiness nor cohesiveness of noodles ws ffected by TG tretments in 13 Koren whet cultivrs. Springiness of cooked noodles regrdless of TG tretments positively correlted with protein content nd SDS-sedimenttion volume. Prk et l. (2006) reported tht the springiness of cooked noodles positively correlted with the volume of SDS sedimenttion in Koren whet cultivrs. Bik et l. (2003) proposed tht the high cohesiveness of cooked noodles could lso be ttributed to strch chrcteristics. Therefore, the differences of springiness nd cohesiveness of cooked noodles with 0.4% of TG tretments between Tble 3 nd Tble 6 could be influenced by the protein chrcteristics nd mylose content of Koren whet cultivrs. Acknowledgments This reserch ws supported in prt by Ntionl Agend Progrms for Agriculturl R&D of Rurl Development Administrtion (PJ ) nd the Next-Genertion BioGreen 21 Progrm (Plnt Moleculr Breeding Center No. PJ008006), Republic of Kore. References AACC Interntionl Approved Methods of Anlysis, 11th Ed. Methods , , , , nd Avilble online only. AACCI: St. Pul, MN, USA Autio, K., Kruus, K., Knpil, A., Gerber, N., Flnder, L. nd Buchert, J Kinetics of trnsglutminseinduced cross-linking of whet proteins in dough. Journl of Agriculturl nd Food Chemistry 53: Axford, D.W.E., McDermott, E.E. nd Redmn, D.G Note on the sodium dodecyl sulfte test of bredmking qulity: Comprison with Pelshenke nd Zeleny tests. Cerel Chemistry 56: Bik, B-K., Prk, C.S., Pszczynsk, B. nd Konzk, C.F Chrcteriztion of noodles nd bred prepred from double-null prtil wxy whet. Cerel Chemistry 80: Bsmn, A., Koksel, H. nd Ng, P.K.W Effects of incresing levels of trnsglutminse on the rheologicl properties nd bred qulity chrcteristics of two whet flours. Europen Food Reserch nd Technology 215: Buer, N., Koehler, P., Wieser, H. nd Schieberle, P Studies on effects of microbil trnsglutminse on gluten proteins of whet. II. Rheologicl properties. Cerel Chemistry 80: Bonet, A., Blszczk, W. nd Rosell, C.M Formtion of homopolymers nd heteropolymers between whet flour nd severl protein sources by trnsglutminsectlyzed cross-linking. Cerel Chemistry 83: Cbllero, P.A., Go mez, M. nd Rosell, C.M Improvement of dough rheology, bred qulity nd bred shelf-life by enzymes combintion. Journl of Food Engineering 81: Choy, A-L., Hughes, J.G. nd Smll, D.M The effect of microbil trnsglutminse, sodium steroyl lctylte nd wter on the qulity of instnt fried noodles. Food Chemistry 122: Gn, C.Y., Ong, W.H., Wong, L.M. nd Es, A.M Effects of ribose, microbil trnsglutminse nd soy protein isolte on physicl properties nd in-vitro strch digestibility of yellow noodles. LWT - Food Science nd Technology 42: Gerrrd, J.A., Fyle, S.E., Wilson, A.J., Newberry, M.P., Ross, M. nd Kvle, S Dough properties nd crumb strength of white pn bred s ffected by microbil trnsglutminse. Journl of Food Science 63: Gerrrd, J.A., Newberry, M.P., Ross, M., Wilson, A.J., Fyle, S.E. nd Kvle, S Pstry lift nd croissnt volume s ffected by microbil trnsglutminse. Journl of Food Science 65: Gibson, T.S., Qll, H.A. nd McClery, B.V An improved method for the mesurement of strch dmge in whet flour. Journl of Cerel Science 15: Hou, G Orientl noodles. Advnces in Food nd Nutrition Reserch 43: Kho, B-K. nd Ng, P.K.W Effects of ferulic cid nd trnsglutminse on hrd whet flour dough nd bred. Cerel Chemistry 86: Kovács, M.I.P., Fu, B.X., Woods, S.M. nd Khn, K Therml stbility of whet gluten protein: Its effect on dough properties nd noodle texture. Journl of Cerel Science 39: Kurishi, C., Ymzki, K. nd Sus Y Trnsglutminse nd Its utiliztion in the food industry. Food Reviews Interntionl 17: Lrre, C., Denery-Ppini, S., Popineu, Y., Deshyes, G., Desserme, C. nd Lefebvre, J Biochemicl nlysis nd rheologicl properties of gluten modified by trnsglutminse. Cerel Chemistry 77: Morrison, W.R. nd Lignelet, B An pproved

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