Food Research International 53 (2013) 63–72

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Diversity in grain, flour, dough and gluten properties amongst Indianwheat cultivars varying in high molecular weight subunits (HMW-GS)

Amritpal Kaur a, Narpinder Singh a,⁎, Arvind Kumar Ahlawat b, Seeratpreet Kaur a, Anju Mahendru Singh b,Harshita Chauhan a, Gyanendra Pratap Singh b

a Department of Food Science and Technology, Guru Nanak Dev University, Amritsar 143005, Indiab Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India

⁎ Corresponding author. Fax: +91 183 2258820.E-mail address: narpinders@yahoo.com (N. Singh).

0963-9969/$ – see front matter © 2013 Elsevier Ltd. Allhttp://dx.doi.org/10.1016/j.foodres.2013.03.009

a b s t r a c t

a r t i c l e i n f o

Article history:Received 2 December 2012Accepted 9 March 2013Available online 19 March 2013

Keywords:Wheat flourPastingDough rheologyFarinographDynamic rheometryGluten indexParticle sizeHMW glutenins subunits

Physico-chemical and rheological properties of Indian wheat cultivars varying in HMW-GS were evaluated.Cultivars having subunits of: 20 (GLU-B1) and 2 + 12 (GLU-D1) exhibited very weak dough stability (DS)i.e. 1.7–1.9 min; 2 + 12 (GLU-D1) and 7 + 9 (GLU-B1) as well as 5 + 10 (GLU-D1) with 7 or 7 + 9(GLU-B1) were weak (2.8–4.4 min) and 17 + 18 (GLU-B1) with 2 + 12 or 5 + 10 (GLU-D1) and 7 + 8(GLU-B1) with 5 + 10 (GLU-D1) were strong (8.8–13.8 min). Hardness showed negative correlation withflour recovery and fine particles. Gluten index (GI) did not show any relationship with protein and DS howeverwas negatively correlatedwith gluten content (GC). GI and GC should be cautiously usedwhile evaluating Indianwheat quality. DS was positively correlated with sedimentation value (SV) and negatively with GC. Water ab-sorption was positively correlated with protein and dry gluten while negatively with SV and gluten scores.Fine particles affect significantly DS and development time. G′ and G″ of gluten was positively correlated withSV and DS.

© 2013 Elsevier Ltd. All rights reserved.

1. Introduction

Numerous wheat cultivars are grown in different countries that varyin yield, resistance towards attack by insects/diseases and grain quality.The flour functionality is influenced by many factors such as cultivartype, protein content, grain hardness, growing condition and crop sea-son (Nemeth, Williams, & Bushuk, 1994). Both protein fractions andcomposition of glutenin subunits affect dough strength and end usequality, which vary with genotypes and environment (Wieser &Kieffer, 2001). Naeem, Paulon, Irmak, and MacRitchie (2012) reportedthat the polymerization of glutenin subunits, a post-translational pro-cess, occurred during the late stage of grain development when therewas a rapid loss of water from the grain. Glutenins from wheat lineswith HMW-GS associated with dough strength started to polymerizeearlier and reach higher MWs than lines with HMW-GS associatedwith dough weakness. They explained the faster polymerization by ahigher concentration of S\H groups as reactants in the formation ofS\S bonds in the polymerization reaction.

Wheat flour when mixed with appropriate quantity of water gives aviscoelastic mass called “dough”. Gluten proteins are responsible for theviscoelastic property of wheat flour dough. The strong flour is obtainedfrom hard wheat that has high protein content and is considered best

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for breadbaking,while softwheatflour of lowprotein content is suitablefor making cookies since it produces cookies with a large spread factorwith fine grain texture (Gaines, Kassuba, & Finney, 1993). Compositionalvariations in the flours from different wheat cultivars and flour streamsfrom the same cultivar vary in dough rheological and baking properties(Fustier, Castaigne, Turgeon, & Biliaderis, 2007).

Indianwheat cultivars differ in their composition and functionality ascompared towheat grown elsewhere (Singh, Singh, &MacRitchie, 2011).Flours made from majority of these cultivars have protein contentbetween 9 and 10% and are considered suitable for chapatti making.Majority of Indian wheat cultivars that are commercially grown havehard texture endosperm with medium protein content and weak glutenstrength. The analysis of polymeric proteins in Indian wheat cultivarsshowed glutenins, gliadin and glutenin to gliadin ratio ranged between28.14 and 40.44%, 45.33 and 55.83% and 0.50 and 0.89, respectively(Singh et al., 2011). About 80 to 85% of the wheat produced in India isconsumed in the form of chapatti and only 15–20% is consumed in theform of biscuits, bread, cakes, noodles and other products. The grain,flour, dough andglutenproperties are evaluatedbydifferent tests tomea-sure the quality of wheat cultivars. At present baking industry, R & DLaboratories and wheat breeding departments in India evaluate wheatflour quality on the basis of gluten content (both wet and dry), proteincontent, gluten index, sedimentation value and dough rheology. How-ever, it has been observed that some of these properties many timesdid not relate to wheat quality, hence, are considered an unreliablemethod. Bonfil and Posner (2012) also did not observed any correlation

64 A. Kaur et al. / Food Research International 53 (2013) 63–72

between gluten index and quality parameters such as SDS-sedimentationand loaf volume amongst Israeli wheat cultivars. These authors sug-gested that the gluten index may be cautiously used while evaluatingIsraeli wheat cultivars. There is hardly any study that has reported therelationship between grains, flour, dough and gluten characteristicsfor Indian wheat cultivars. The objectives of the present study were toevaluate (i) diversity in grain, flour, dough and gluten propertiesamongst Indian wheat cultivars varying in high molecular weight sub-units and (ii) to see the relationship between grains, flour, dough andgluten characteristics.

2. Materials and methods

2.1. Materials

Wheat cultivars viz. HD2687, PBW175, HD2888, HD2985, C306,DBW14, HI1563, HD2643, DL788-2, HD2967, HD2987, PBW343,DBW17, CBW39, PBW590, HD2864, NI5439 and CBW38 from 2012harvest were supplied by Indian Agricultural Research Institute,Pusa Road, Delhi.

2.2. Grain colour characteristics

L*, a* and b*values were determined using Hunter colorimeterModel D 25 optical sensor (Hunter Associates).

2.3. Grain weight, diameter and hardness index

Grain hardness index (GHI), diameter and thousand kernel weight(TKW) were analysed with Single Kernel Characterization system(SKCS) 4100 (Perten Instruments, Australia) using AACC method55-31 (2000). All dockage was removed from the sample using seedcleaner and 20 g of seed was used for analysis. Using the samplescoop, the seed was placed in the inlet hopper and the sample hopperknobwas turned clockwise to the hopper door. Themoisture content ofgrains ranged between 10 and 11%. The weight, diameter and hardnesswere recorded for 250 seeds of each sample and TKW was calculated(TKW).

2.4. Protein content

Grain and flour samples were evaluated for protein content(N% × 5.7) using AACC method 46-30 (2000).

2.5. SDS-PAGE analysis

Glutenin fraction from different wheat varieties was isolated by themethod of Fu and Sapirstein (1996). The fractionwas suspended in a so-lution containing sodium dodecyl sulphate (4%), β-mercaptoethanol(5%), bromophenol blue (0.001%), glycerol (20%) and 0.06 M Tris–HCl(pH 6.8), incubated (60 °C/1 h), centrifuged (10,000 ×g for 10 min)and the supernatant (20 μl) was loaded in the gel. SDS-PAGE analysiswas carried out according to Laemmli (1970) and as modified by Singhand Shepherd (1985), in 10% polyacrylamide gels. Gels were stainedovernight using 0.1% (w/v) Coomassie Brilliant Blue R-250 solution.High molecular weight glutenin subunits (HMW-GS) were numberedaccording to the nomenclature proposed by Payne and Lawrence(1983).

2.6. Sedimentation value

SDS-sedimentation values of meal and flour were determined usingthe method of Axford, McDermott, and Redman (1979).

2.7. Falling number

Falling number value of flour samples was determined using FallingNumber apparatus using AACC method 56-81B (2000).

2.8. Flour milling

The grains were conditioned for 48 h at 14% moisture and milledin the Quadrumat Senior mill (Brabender, Germany).

2.9. Particle size distribution

Particle size distribution of the flour was measured by laser scatter-ing using a Malvern Mastersizer Hydro2000S, (Malvern InstrumentsLtd., UK). Flour samples were added to the sample port to reach an ob-scuration of 1–2%. The size distribution was expressed in terms of thevolumes of equivalent spheres.

2.10. Pasting properties

The pasting properties of flours from different wheat cultivars wereevaluated with Rapid Visco-Analyzer (RVA-4, Newport Scientific,Warriewood, Australia) using standard profile I. Flour (3 g, 14% mois-ture basis) was weighed directly in an aluminium RVA sample canister,and 25 ml distilled water was added. A programmed heating andcooling cycle was used where the samples were held at 50 °C with aspeed of 960 rpm for 10 s. Then the speed was decreased to 160 rpmand held at 50 °C for 1 min, and then heated to 95 °C for 3.7 min andheld at 95 °C for 2.5 min before cooling to 50 °C in 3.8 min and holdingit for 2 min. Parameters recorded were peak viscosity, trough viscosity,breakdown viscosity, final viscosity, setback viscosity and pasting tem-perature. Stirring number was determined using AACC method 22-08(2000).

2.11. Gluten content

Wet gluten, dry gluten and gluten index was analysed usingGlutomatic 2200 (Perten Instruments) according to AACC method38-12A (2000).

2.12. Farinographic characteristics

Dough mixing properties were analysed using 10 g (14% moisturebasis) Farinograph (Brabender OHG, Germany) according to AACCmethod 54-21 (2000). Water absorption, dough development time,dough stability, degree of softening andquality numberweredetermined.

2.13. Dynamic rheology of dough and gluten

Dynamic rheology was measured using a Rheostress 6000 dynamicrheometer (Haake, ThermoScientific, Germany). The plate andplate sys-tem was used with a diameter of 30 mm and a gap between plates of2 mm. The sample (dough or gluten) was placed between the plates ofthe rheometer and excess sample was removed carefully by using asharp razor blade. A thin layer of silicon oil was applied to the exposedsurface of the sample to prevent drying during testing. The samplewas rested for 10 min to allow relaxation of stresses generated duringsample loading before the measurement. Stress sweep tests (1 Hz at25 °C) were made to determine the linear viscoelastic region (LVR) ofall samples; a stress value of 1 Pa was chosen for all the frequencytests. G′ (elastic modulus), G″ (viscous modulus) and tan δ (G″/G′) fordough samples were measured. G′, G″ and tan δ for freshly extractedwet gluten samples was determined during heating from 25 °C to90 °C at rate of 1 °C/min followed by cooling to 50 °C at the same rate.

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2.14. Statistical analysis

The data reported are average of three replications. All the results areexpressed at 14% moisture basis otherwise stated. The data wassubjected to analysis of variance (ANOVA) by Duncan's test (p ≤ 0.05)using Minitab Statistical Software (State College, PA). Pearson correla-tion (r) and principal component analysis (PCA) were also carried outfor determining the relationship between different variables. The PCAresults were graphically represented by the projection of the first twoprincipal components.

3. Results and discussion

3.1. Grain characteristics

The physical properties for grains from different wheat cultivars areshown in Table 1. L* value, an indicator of degree of lightness, of grainsfrom different wheat cultivars ranged between 57.22 (HD2643) and63.37 (NI5439). The a* and b* values ranged between 5.72 (NI5439)and 7.13 (C306) and between 17.76 (NI5439) and 20.79 (HD2864). L*,a* and b* values of majority of cultivars ranged from 58 to 60, 6.2 to 7,and 18 to 20, respectively. HD2864, HD2967, and HD2985 had higherb* values indicating the presence of greater yellowness. NI5439 showedthe least a* and b* values indicating the least redness as well as yellow-ness. TKW and grain diameter of different cultivars ranged from 34.3 to45.7 g and 2.7 to 3.4 mm, respectively. HD2864 showed the lowestTKW and grain diameter while NI5439 showed the highest. NI5439showed the highest grain diameter. TKW and grain diameter showednegative correlation with a* values (r = −0.535 and −0.459, respec-tively, p ≤ 0.05, Table 2). The cultivars with higher a* values showedlower grain diameter. The cultivars with greater grain diameter showedhigher TKW and a strong correlation was observed between them (r =0.770, p ≤ 0.05).

Grain hardness is associated with the milling properties of wheat. Itdetermines the way in which components are packed in endospermcells. It indicates the resistance of the grains to fracture as well as abilityto reduce into fine flour. GHI ranged between 66 and 90 (Table 1).NI5439 had the least GHIwhereas C306had the highest amongst the cul-tivars studied.Majority of the cultivars showed that GHI ranged between75 and 80. Pearson, Wilson, Gwirtz, Maghirang, Dowell, McCluskey &Bean (2007) classified US wheat cultivars of different classes (hard red

Table 1Physical properties, protein content and flour recovery of different wheat cultivars.

Cultivars Hunter colour parameters TKW (g)

L* value a* value b* value

CBW38 61.15 ± 0.30g 6.23 ± 0.33bc 17.8 ± 0.39a 37.8 ± 0.39cHD2987 58.77 ± 0.43d 7.06 ± 0.22e 19.6 ± 0.24e 39.9 ± 1.2dHD2985 60.31 ± 0.34f 6.76 ± 0.34d 20.45 ± 0.45f 40.8 ± 0.70dHD2864 60.91 ± 0.45g 7.02 ± 0.31e 20.79 ± 0.41f 35.8 ± 0.68bPBW590 57.45 ± 0.54a 6.48 ± 0.4cd 18.65 ± 0.36cd 37.2 ± 0.62cNI5439 63.37 ± 0.51h 5.72 ± 0.51a 17.76 ± 0.46a 45.7 ± 0.46gHI1563 57.69 ± 0.23a 6.11 ± 0.38ab 17.96 ± 0.41ab 42.2 ± 0.67eHD2967 59.52 ± 0.67b 7.02 ± 0.46e 20.09 ± 0.34g 34.3 ± 1.1aCBW39 60.2 ± 0.32f 6.89 ± 0.30de 19.86 ± 0.34f 42.1 ± 0.63ePBW175 59.68 ± 0.48ef 6.95 ± 0.38de 19.61 ± 0.47ef 42.7 ± 0.73efHD2643 57.22 ± 0.56a 6.55 ± 0.35cd 18.45 ± 0.43c 43.2 ± 0.83fHD2687 57.93 ± 0.45ef 6.87 ± 0.34de 18.21 ± 0.36bc 38.1 ± 1.0cDL788-2 58.3 ± 0.26ab 6.64 ± 0.36cd 18.62 ± 0.32cd 40.2 ± 1.0dDBW17 58.34 ± 0.32ab 7.05 ± 0.39e 19.81 ± 0.22f 40.7 ± 1.1dPBW343 60.94 ± 0.56g 6.11 ± 0.45ab 18.04 ± 0.46ab 43.6 ± 0.62fDBW14 59.94 ± 0.67 6.69 ± 0.40d 19.37 ± 0.41 36.2 ± 1.1bC306 58.13 ± 0.12 7.13 ± 0.22e 18.94 ± 0.34 36.2 ± 1.2bHD2888 58.09 ± 0.84 6.65 ± 0.38cd 18.67 ± 0.37 43.2 ± 0.94f

Means with similar letters in a column do not differ significantly (p ≤ 0.05).

spring, hard red winter, hard white spring and hard white winter) ashard, which had a GHI between 53 and 78.

GHI showed a negative correlation with TKW (r = −0.479,p ≤ 0.05) and L* value (r = −0.589, p ≤ 0.05). This indicated that thecultivars with lower TKW and light coloured grains might have the com-pact structured endosperm that resulted in higher GHI. A positive signif-icant correlation of GHIwith grain protein content (r = 0.431, p ≤ 0.05)as well as a* value (r = 0.466, p ≤ 0.05) was observed. A positive corre-lation between grain hardness and protein content was also reportedearlier (Slaughter, Norris, & Hruschka, 1992).

Protein content of grain from different cultivars ranged between10.57 (PBW175) and 13.95% (HD2888). Majority of the cultivarsshowed protein content between 11 and 12.5% (Table 1). Variationin protein content might be attributed to environmental and growingconditions as well as genetic makeup of the cultivars.

3.2. Flour recovery

Flour recovery varied between 67 and 73.1%, and was negativelyrelatedwith GHI andprotein content (Table 1). However, the correlationof flour recovery with GHI was significant (r = −0.707, p ≤ 0.005,Table 2). C306, HD2687, HD2888 and PBW590 with higher GHI(81–90) showed flour yields between 67.4 and 69.2%, whereasDBW17, PBW343, CBW39, HI1563 and HD2985 with lower GHI(70–74) showed higher flour recovery (70–72.7%). Wheat cultivarswith lower grain L* values gave lower flour recovery. HD2888, C306and PBW590 having L* values ranging from 57.45 to 58.18 showedflour recovery between 67 and 68.4%. Contrarily, NI5439, PBW343 andHD2864 with L* values ranging between 60.9 and 63.37 showed flourrecovery ranging between 72.2 and 73.1%. A significant correlation be-tween L* and flour recovery was observed (r = 0.443, p ≤ 0.05).Wheat cultivars with greater hardness index showed lower TKW andflour recovery. This may be attributed to a lower endosperm–bran ratio.TKW showed significant correlation with GHI (r = −0.479 ≤ 0.05) anddiameter (r = 0.770, p ≤ 0.005, Table 2)

3.3. Flour characteristics

3.3.1. Hunter colour parameterL*, a* and b* values of flours from different cultivars are shown in

Table 3. DBW 14 and HD 2888 flours showed the least L* (92.8) value

Diameter (mm) Hardness index Protein content(%N × 5.7)

Flour recovery (%)

2.88 ± 0.19bc 80 ± 2.46f 12.23 ± 0.29 68.4 ± 0.55bc2.88 ± 0.21bc 76 ± 2.32d 11.6 ± 0.35cd 68.1 ± 0.46b2.96 ± 0.19cd 74 ± 2.45cd 11.64 ± 0.39cd 71.1 ± 0.53d2.70 ± 0.19ab 77 ± 2.32de 12.31 ± 0.34fg 73.1 ± 0.72g2.82 ± 0.22ab 81 ± 2.39fg 13.84 ± 0.30k 68.4 ± 0.60bc3.27 ± 0.20ef 66 ± 3.42a 12.22 ± 0.25ef 72.2 ± 0.60ef2.82 ± 0.18ab 74 ± 2.29cd 11.24 ± 0.35b 71.7 ± 0.55e2.93 ± 0.16bcd 80 ± 2.42f 12.73 ± 0.34ghi 68.8 ± 0.60c3.01 ± 0.19cd 72 ± 2.36bc 12.79 ± 0.36hi 71.6 ± 0.44e2.99 ± 0.17cd 80 ± 2.97f 10.57 ± 0.27a 68.6 ± 0.47bc3.08 ± 0.21de 79 ± 2.51ef 13.41 ± 0.30j 69.7 ± 0.48d2.89 ± 0.16bc 87 ± 2.25h 13.5 ± 0.35jk 69.2 ± 0.56c2.86 ± 0.24bc 80 ± 2.69f 11.36 ± 0.38bc 71.8 ± 0.52e2.97 ± 0.20cd 71 ± 2.13b 11.91 ± 0.34de 68.11 ± 0.6b3.4 ± 0.23f 70 ± 2.49b 12.32 ± 0.33ef 72.7 ± 0.74fg

2.68 ± 0.28a 72 ± 2.85bc 12.12 ± 0.28ef 70.0 ± 0.5d2.82 ± 0.15ab 90 ± 4.11h 13.21 ± 0.25ij 67.4 ± 0.56a3.12 ± 0.16de 83 ± 3.50g 13.95 ± 0.31k 67.0 ± 0.52a

Table 2Pearson correlation between grain and flour properties.

TKW L*(Grain)

GHI GPC Particles1–10 μm

Particles10–20 μm

Particles50–100 μm

Particles100–200 μm

FPC WetGluten

Drygluten

SV DS FN

a* (Grain) −0.535⁎ 0.466⁎ 0.507⁎ −0.609⁎⁎

GHI −0.479⁎ −0.589⁎ 0.444⁎ −0.499⁎ 0.441⁎

L* (Flour) −0.447⁎ 0.401⁎ 0.494⁎ 0.517⁎ 0.483⁎ 0.637⁎⁎

GD 0.770⁎⁎

FR −0.707⁎⁎ −0.616⁎⁎ −0.500⁎ 0.813⁎⁎

a* (Flour) −0.442⁎ −0.503⁎

FPC 0.813⁎⁎ 0.819⁎⁎ −0.480⁎

GI −0.613⁎⁎ −0.563⁎

WA −0.410⁎ 0.482⁎ 0.583⁎ 0.467⁎ −0.437⁎ −0.489⁎

DS 0.576⁎ −0.409⁎ −0.677⁎⁎ −0.603⁎⁎ −0.635⁎⁎ 0.794⁎⁎

DDT −0.470⁎ 0.468⁎

DOS 0.480⁎ 0.429⁎ −0.696⁎⁎

PV 0.536⁎ 0.652⁎⁎

BV 0.508⁎ −0.591⁎

FV 0.451⁎ 0.468⁎

PT −0.499⁎ 0.694⁎⁎ −0.444⁎ −0.580⁎

G′ Dough −0.561⁎ 0.598⁎⁎

G″ Dough −0.445⁎ 0.535⁎

G′ 90 °C Glu −0.598⁎⁎ −0.673⁎⁎ −0.604⁎⁎ 0.524⁎

G′ 50 °C Glu −0.452⁎ −0.518⁎ −0.620⁎⁎ −0.593⁎⁎ 0.407⁎

G″ 90 °C Glu 0.430⁎⁎ −0.631⁎⁎ −0.642⁎⁎ −0.657⁎⁎ 0.464⁎ 0.557⁎

G″ 50 °C Glu −0.593⁎⁎

Tan δ 90 °C Glu 0.429⁎

Tan δ 50 °C Glu 0.409⁎ 0.627⁎⁎ 0.495⁎ 0.422⁎

TKW, thousand kernel weight; GHI, grain hardness index; GPC, grain protein content; FPC, flour protein content; SV, sedimentation value; DS, dough stability; FN, falling number;GD, grain diameter; FR, flour recovery; GI, gluten index; WA, water absorption; DDT, dough development time; DOS, degree of softening; PV, peak viscosity; BV, breakdownviscosity; FV, final viscosity; PT, pasting temperature; Glu, gluten⁎ p ≤ 0.05.

⁎⁎ p ≤ 0.005.

66 A. Kaur et al. / Food Research International 53 (2013) 63–72

while HD 2987 flour showed the highest L* value (94.0). NI 5439 flourshowed the lowest a* value (0.18) while DBW 17 flour had thehighest a* value (0.38). NI 5439 flour had the highest b* value(11.01) while HI 1563 flour had the lowest (7.4). Flours with higherL* value showed lower protein content. Difference in colour parametersamongst flours from different cultivars may be attributed to differencein xanthophyll and its ester content, ash content and particle size distri-bution in the flours. Majority of the cultivars showed L*, a* and b* valuesin the range of 93.0–93.6, 0.30–0.35 and 9.5–11, respectively. In general,flours with higher proportion of particles with sizes between 1 and

Table 3Hunter colour parameters and particle size distribution of flours milled from different whe

Cultivars Hunter colour parameters Particles size distribut

L* a* b* 1–10μm

10–2μm

CBW38 93.67 ± 0.16d 0.28 ± 0.02b 7.65 ± 0.35a 2.86 ± 0.06j 7.39HD2987 94.04 ± 0.40d 0.22 ± 0.03a 7.99 ± 0.34b 2.27 ± 0.07g 5.6HD2985 93.72 ± 0.37d 0.23 ± 0.04a 9.39 ± 0.36de 2.56 ± 0.06i 6.4HD2864 93.04 ± 0.36a 0.31 ± 0.02bc 9.38 ± 0.23de 1.85 ± 0.05d 5.21PBW590 93.35 ± 0.35abc 0.34 ± 0.03c 8.65 ± 0.36c 2.16 ± 0.06f 5.90NI5439 93.6 ± 0.29cd 0.18 ± 0.03a 11.01 ± 0.35g 3.18 ± 0.04j 6.45HI1563 94.03 ± 0.24d 0.2 ± 0.04a 7.45 ± 0.35a 1.95 ± 0.05e 5.02HD2967 93.55 ± 0.28c 0.33 ± 0.04bc 9.2 ± 0.39d 1.56 ± 0.07b 5.81CBW39 93.36 ± 0.38abc 0.34 ± 0.03 10.45 ± 0.36fg 2.22 ± 0.05fg 6.64PBW175 93.55 ± 0.39c 0.36 ± 0.03c 9.18 ± 0.37d 1.07 ± 0.04a 4.34HD2643 93.68 ± 0.33d 0.28 ± 0.03b 9.27 ± 0.31d 2.02 ± 0.05e 5.44HD2687 93.24 ± 0.34abc 0.35 ± 0.04c 10.14 ± 0.37f 2.46 ± 0.04h 7.05DL788-2 93.29 ± 0.44abc 0.32 ± 0.04bc 9.49 ± 0.33de 1.89 ± 0.04d 4.99DBW17 93.22 ± 0.34abc 0.38 ± 0.03 10.69 ± 0.37g 1.65 ± 0.04c 6.34PBW343 93.46 ± 0.39bc 0.36 ± 0.03c 10.2 ± 0.38f 2.39 ± 0.05h 7.10DBW14 92.90 ± 0.37a 0.3 ± 0.04b 9.56 ± 0.37de 2.02 ± 0.04e 6.61C306 93.12 ± 0.38a 0.3 ± 0.04b 10.87 ± 0.32g 1.12 ± 0.04a 4.85HD2888 92.9 ± 0.33a 0.3 ± 0.05b 9.7 ± 0.45ef 1.10 ± 0.05a 7.39

Means with similar letters in a column do not differ significantly (p ≤ 0.05).

45 μm had higher L* and lower a* values. However, correlation coeffi-cients of particles with sizes of 1–10 μm with a* values were signifi-cant (r = −0.444, p ≤ 0.05, Table 2).

3.3.2. Particle size distributionMajority of the flours showed unimodal particle size distributions. A

wide range of particle size distribution was observed in flours and par-ticle sizes ranged between 1 and 300 μm (Table 3). Fine particles of1–10 μm size ranged between 1.07 and 3.18%. Particles of 50–100 μmsize constituted a major portion of the flours milled from different

at cultivars.

ion (%)

0 20–45μm

50–100μm

100–200μm

200–300μm

± 0.32g 16.69 ± 0.46fg 41.04 ± 0.69a 29.99 ± 0.5c 2.04 ± 0.28b± 0.31cd 15.57 ± 0.54cd 42.39 ± 0.61c 31.89 ± 0.45e 2.29 ± 0.30c± 0.26f 16.71 ± 0.47fg 42.66 ± 0.52de 29.74 ± 0.44bc 1.95 ± 0.13ab± 0.22bc 15.83 ± 0.44de 44.87 ± 0.73g 30.33 ± 0.43c 1.87 ± 0.29ab± 0.36e 17.07 ± 0.46gh 41.62 ± 0.68ab 30.82 ± 0.43d 2.42 ± 0.25cd± 0.39f 15.28 ± 0.44bc 41.34 ± 0.65ab 31.31 ± 0.46d 2.43 ± 0.28cd± 0.46b 15.05 ± 0.41b 44.69 ± 0.68g 31.3 ± 0.44d 1.97 ± 0.19ab± 0.29e 17.76 ± 0.35i 42.83 ± 0.70e 30.0 ± 0.49c 2.06 ± 0.21b± 0.36f 16.32 ± 0.55ef 41.63 ± 0.68ab 30.97 ± 0.48d 2.21 ± 0.22bc± 0.21a 13.00 ± 0.48a 43.63 ± 0.65f 35.07 ± 0.45f 2.91 ± 0.11e± 0.21cde 15.28 ± 0.45bc 42.5 ± 0.67cd 32.3 ± 0.39e 2.46 ± 0.26cd± 0.13g 17.89 ± 0.36jde 41.11 ± 0.65a 29.42 ± 0.37a 2.05 ± 0.20b± 0.14b 15.69 ± 0.52cd 43.11 ± 0.67ef 32.01 ± 0.47e 2.33 ± 0.21c± 0.28f 15.13 ± 0.53b 41.91 ± 0.69bc 32.42 ± 0.38e 2.54 ± 0.34cd± 0.22g 17.33 ± 0.48hi 42.57 ± 0.66cd 28.9 ± 0.37a 1.7 ± 0.25a± 0.29f 17.03 ± 0.41gh 41.14 ± 0.70a 30.88 ± 0.23d 2.31 ± 0.26c± 0.42b 12.74 ± 0.53a 43.36 ± 0.74ef 35.02 ± 0.49f 2.89 ± 0.26e± 0.32g 12.73 ± 0.13a 43.6 ± 0.68f 34.99 ± 0.38f 2.76 ± 0.28de

67A. Kaur et al. / Food Research International 53 (2013) 63–72

cultivars followed by particles of 100–200 μm > 20–45 μm > 10–20 -μm > 200–300 μm > 1–10 μm size. Wheat cultivars with higher GHIshowed a lower proportion of particles of 1–45 μm size whereas culti-vars with lower GHI showed greater proportion of 50–300 μm size par-ticles. However, GHI showed a negative significant correlation withparticles of 1–10 μm size (r = −0.499, p ≤ 0.05). C306 with thehighest GHI (90) showed the least proportion (1.12%) of fine particles(1–10 μm). GHI showed a significant positive correlation with grainprotein content (r = 0.444, p ≤ 0.05). Results suggested that thewheat cultivars with softer endosperm are crushed easily, and produceintact starch granules and fine flour, whereas starch granules of hardwheat are tightly bound to the proteinmatrix, requiring greater millingenergy and producing coarse flourwith higher levels of damaged starch(Bekes, 2012).

3.3.3. Protein content and gluten characteristicsWheat cultivars having the grains with higher protein content

resulted into flours with higher protein content. Grain and flour proteincontents were significantly correlated (r = 0.464,≤0.05, Table 2) witheach other. Wet and dry gluten content ranged from 21.7 to 33.3% and7.5% to 11.6%, respectively (Table 4). Flour protein content showed asignificant positive correlation with both wet and dry gluten contents(r = 0.813 and 0.891, respectively, p ≤ 0.005). Flour protein contentwas negatively correlatedwith gluten score, though relationwas statis-tically non significant. The GI of flours from different cultivars showed awide range (46–100), and C306, HD2687 and HD2888 flours showedsignificantly lower GI as compared to other cultivars (Table 4). GI didnot show any significant relationship with flour protein content; how-ever, it was negatively correlated with wet and dry gluten contents(r = −0.613, −0.563, respectively, p ≤ 0.05). Bonfil and Posner(2012) also did not observe any correlation of GI with protein contentand sedimentation value. They reported that many Israeli wheat culti-vars with lower GI exhibited good dough and bread quality. Our resultsalso supported the observations of Bonfil and Posner (2012) that GI beused with caution while evaluating the wheat quality.

3.3.4. High molecular weight glutenins subunitsHigh molecular weight glutenins subunit patterns represented in

different wheat cultivars were: 7, 20, 7 + 8, 7 + 9 and 17 + 18.C306 and HD2888 showed that subunits of 20 for Glu-B1 with2 + 12 of Glu-D1 exhibited very weaker dough properties (doughstability 1.7–1.9 min) while PBW175 and HD2643 having a combina-tion of 2 + 12 and 7 + 9 were weaker (dough stability of 3.7 and4.4 min, respectively). CBW38 and HD2985 with subunits of 17 + 18

Table 4Protein content, gluten content, gluten index, falling number value and sedimentation valu

Cultivars Protein content(% N × 5.7)

Wet gluten(%)

Dry Gluten(%)

CBW38 8.65 ± 0.38a 23.31 ± 1.25b 7.67 ± 0.43aHD2987 10.63 ± 0.46e 22.2 ± 0.95a 8.07 ± 0.47bHD2985 10.21 ± 0.42d 24.4 ± 0.19c 8.38 ± 0.46bHD2864 10.01 ± 0.23cd 25.46 ± 1.10c 8.61 ± 0.40bPBW590 10.94 ± 0.43ef 25.66 ± 1.03cd 9.46 ± 0.26cNI5439 9.24 ± 0.28b 25.46 ± 1.04c 8.3 ± 0.33bHI1563 9.64 ± 0.15bc 21.68 ± 0.97a 7.48 ± 0.41aHD2967 11.95 ± 0.54h 33.31 ± 1.32h 10.79 ± 0.50CBW39 11.38 ± 0.46g 32.83 ± 0.95gh 10.8 ± 0.27dPBW175 10.57 ± 0.50d 26.93 ± 1.0e 8.97 ± 0.30cHD2643 11.46 ± 0.41fg 29.87 ± 1.04f 10.1 ± 0.35dHD2687 10.73 ± 0.32ef 26.94 ± 1.17e 9.3 ± 0.30cDL788-2 10.64 ± 0.44e 26.51 ± 0.73de 9.64 ± 0.50DBW17 11.16 ± 0.28fg 26.92 ± 1.60e 9.27 ± 0.43cPBW343 11.63 ± 0.37g 29.13 ± 0.62f 9.92 ± 0.42dDBW14 10.19 ± 0.42d 25.0 ± 1.30c 8.21 ± 0.23bC306 12.02 ± 0.38h 32.05 ± 0.8g 11.56 ± 0.52HD2888 11.71 ± 0.36h 32.35 ± 1.2gh 10.81 ± 0.47

Means with similar letters in a column do not differ significantly (p ≤ 0.05).

of Glu-B1 in combination with 2 + 12 or 5 + 10 as well as HD2987with subunits of 7 + 8 of Glu-B1 with 5 + 10 were stronger withdough stability ranged between 8.8 and 13.8 min. However, PBW343and DBW17 with subunits of 5 + 10 of Glu-D1 in combination witheither 7 or 7 + 9 of Glu-B1 were weaker with dough stability of 2.8and 3.3 min, respectively. The selection of wheat for 5 + 10 subunitsof Glu-D1 was most widely used (MacRitchie, du Cros, & Wrigley,1990). Shewry et al. (2003) associated subunits of 20 with inferiordurum wheat weak dough strength. Sissons, Ames, Hare, and Clarke(2005) associated subunits of 20 expressions to weak gluten strength.The glutenins subunits 5 + 10 and 2 + 12, respectively, were reportedto be positively and negatively correlated to strong and weak glutenstrength (Payne, 1987). Lafiandra, D'Ovidio, Porceddu, Margiotta, andColaprico (1993) and Popineau, Cornec, Lefebvre, and Marchylo(1994) have associated the presence of 5 + 10 subunits to a visco-elastic gluten and the gluten visco-elasticity substantially decreasedwhen 5 + 10 subunits were substituted with allelic 2 + 12. Naeem etal. (2012) reported that glutenins fromwheat lines with HMW-GS asso-ciated with dough strength (e.g. 5 + 10 at Glu-D1 and 7 + 9 at Glu-B1)started to polymerize earlier and reached to higherMWs than lineswithHMW-GS associated with dough weakness (e.g. 2 + 12 at Glu-D1 and20x + 20y at Glu-B1). The faster polymerization was explained by ahigher concentration of S\H groups as reactants in the formation ofS\S bonds in the polymerization reaction.

3.3.5. Falling numberFalling number determines the level of α-amylase in the flour

which increases when the wheat grains are exposed to humid andundesirable climate during storage. Falling number values variedfrom 485 to 967 s (Table 4). HD 2888 had the highest amount ofα-amylase activity as indicated by the lowest falling number value.HD 2687 showed the highest falling number i.e. had less amount ofα-amylase. Majority of the cultivars showed a falling number rangebetween 700 and 800 s indicating these were sound and had lowerα-amylase activity.

3.3.6. Sedimentation valueSDS sedimentation values of flours from different cultivars ranged

from 36 to 56 ml (Table 4). CBW38 flour had the highest sedimentationvalue. Sedimentation value was significantly correlated with doughstability (r = 0.794, p ≤ 0.005). A significant correlation between SDSsedimentation value with the glutenins content and ratio of glutenins:gliadins has been reported earlier (Gil-Humanes, Piston, Rosell, &Barro, 2012). Sedimentation tests have been associated with gluten

e of flours milled from different wheat cultivars.

Gluten index Falling number(sec)

Sedimentation value(ml)

92 ± 2.12g 650 ± 20b 56 ± 3i100 ± 0.71i 720 ± 25c 48 ± 1.8g91 ± 3.54g 715 ± 22c 46 ± 1.5fg96 ± 4.24h 820 ± 20f 42 ± 2de57 ± 2.12d 708 ± 22c 43 ± 1de50 ± 2.41c 790 ± 30e 47 ± 2fg

100 ± 3.54i 712 ± 25c 43 ± 2de51 ± 3.41c 806 ± 30ef 52 ± 2h55 ± 2.12d 884 ± 35g 41 ± 2cd62 ± 2.83e 738 ± 30d 44 ± 1.7ef67 ± 3.54f 758 ± 25d 40 ± 1.7c46 ± 3.24ab 967 ± 30i 43 ± 2de95 ± 3.17h 632 ± 33b 36 ± 1.5a99 ± 4.24i 749 ± 31cd 36 ± 1.5a99 ± 4.24i 810 ± 30ef 38 ± 1.8b63 ± 2.95e 832 ± 23f 41 ± 2cd44 ± 1.41a 901 ± 42h 39 ± 2bc48 ± 3.28bc 483 ± 24a 41 ± 2cd

68 A. Kaur et al. / Food Research International 53 (2013) 63–72

strength and superior bread-making quality (Ayoub, Fregeau-Reid, &Smith, 1993). Sedimentation values in SDS solution were reported tobe due of swelling of glutenins strand (Eckert, Amend, & Belitz, 1993).Doughwith higher strength of gluten hadmore swelling in SDS suspen-sion, hence, showed more sedimentation value. Sedimentation valuedid not show any significant relationship with wet gluten, dry glutenand GI. Sedimentation value showed negative correlation with flourprotein content. Hence, it is not necessary that flours having higherprotein content will give higher sedimentation values.

3.3.7. Pasting propertiesPastingproperties (peak viscosity, breakdownviscosity, pasting tem-

perature, setback viscosity and final viscosity) are shown in Table 5a.Pasting curves of flour from four cultivars is illustrated in Fig. 1a. Peakviscosity represents the equilibrium point between swelling and therupture of starch granules. Peak viscosity of flours ranged from 1278 to2311 cP, HD 2987 had the highest peak viscosity while HD 2987 hadthe lowest. Rupturing of granules because of shearing contributes totrough viscosity. Trough viscosity offlours fromdifferentwheat cultivarsranged from 930 cP (HD2888) to 1471 cP (CBW38). Trough viscosity isinfluenced by the rate of amylose exudation, granule swelling, amylose–lipid complex formation and competition between exudated amyloseand remaining granules for free water. Breakdown was correlated withthe stability of starch granule under high shear condition (Ragaee &Aal, 2006). HD2687 flour had the lowest breakdown viscosity i.e.277 cP while HD 2987 had the highest breakdown (900 cP). HD 2987had higher breakdown viscosity than HD2687 which showed that for-mer had starch granules which were more resistant towards shearing.Protein strengthens the links between the dispersed and continuousphase that provide greater stability during shearing (Fitzgerald, Martin,Ward, Park, & Shead, 2003). Peak viscosity, breakdown viscosity andfinal viscosity were significantly positively correlated to dough stability(r = 0.653, p ≤ 0.005) and sedimentation values of flour (r = 0.536,p ≤ 0.05). This indicated that the higher peak viscosity, breakdown vis-cosity and final viscosity may be attributed to higher glutenins contentand glutenins:gliadins ratio. The glutenins and glutenins:gliadins ratiohas been correlated to SDS sedimentation value earlier (Gil-Humaneset al., 2012). Final viscosity varied between 1774 cP (HD 2888) to2365 cP (CBW38) and majority showed the final viscosity in the rangeof 2100 to 2300 cP. When the paste was subsequently cooled down to

Table 5aPasting and Farinographic characteristics of flours milled from different wheat cultivars.

Cultivars Peak viscosity(cP)

Breakdown viscosity(cP)

Final viscosity(cP)

Setback viscosity(cP)

CBW38 2272 ± 88i 801 ± 16j 2365 ± 105f 894 ± 44abcHD2987 2311 ± 25i 901 ± 24k 2287 ± 30ef 877 ± 52abHD2985 2093 ± 40h 735 ± 24i 2314 ± 50f 956 ± 45dHD2864 1480 ± 55b 438 ± 12d 1957 ± 45b 915 ± 43bcdPBW590 2260 ± 90i 838 ± 34j 2267 ± 95ef 845 ± 45aNI5439 1891 ± 70fg 633 ± 25h 2193 ± 75ef 935 ± 50cdHI1563 1682 ± 30cd 489 ± 25ef 2067 ± 8cd 874 ± 45abHD2967 1797 ± 60ef 537 ± 22g 2269 ± 55ef 1009 ± 65eCBW39 1759 ± 58e 456 ± 12d 2242 ± 80ef 939 ± 52cdPBW175 2096 ± 33h 720 ± 22i 2293 ± 106 917 ± 45bcdHD2643 1278 ± 45a 286 ± 12a 1838 ± 30a 846 ± 46aHD2687 1425 ± 60b 277 ± 16a 2045 ± 35c 897 ± 44abcDL788-2 1862 ± 80fg 662 ± 26h 2079 ± 65cd 879 ± 43abDBW17 1575 ± 75c 324 ± 12b 2148 ± 44d 897 ± 47abcPBW343 1675 ± 40d 368 ± 15c 2208 ± 47e 901 ± 45bcdDBW14 1470 ± 60b 290 ± 14a 2124 ± 76d 944 ± 44cdC306 1866 ± 55fg 515 ± 25fg 2305 ± 55ef 954 ± 38dHD2888 1630 ± 58cd 700 ± 32h 1774 ± 65a 844 ± 50a

Means with similar letters in a column do not differ significantly (p ≤ 0.05).WA, water absorption; DDT, dough development time; DS, dough stability; DOS, degree of

50 °C, the starch reached a final viscosity, which was attributed to theretrogradation or re-association of amylose molecules (Ragaee & Aal,2006). Pasting temperature of flours from different wheat cultivarsranged between 66.15 °C and 68.75 °C, the highest was observed forDBW17 and the lowest for HD 2888. Higher pasting temperature ofDBW17might be attributed to higher water binding capacity, higher ge-latinization and lower swelling of starch granules present in flour(Numfor, Walter, & Schwartz, 1996). Setback value is the recovery ofthe viscosity during cooling of the heated starch suspension and an indi-cator of short-term retrogradation. Setback value ranged from 844 to1009 cP for different wheat cultivars. Higher setback of the flour HD2967 may due to the amount and molecular weight of the amyloseleached from the granules and remnants of the gelatinized starch (Loh,1992). This could infer that products prepared from HD2967 flour willhave higher staling rate as higher setback viscosity is related to higherretrogradation rate. Peak viscosity, breakdown viscosity andfinal viscos-ity were interrelated to each other. Flours with higher peak viscosityshowed higher breakdown and final viscosity. The results indicatedthat the proteins seem to provide some protection against the break-down. Earlier a strong negative correlation (−0.768, p ≤ 0.005) ofbreakdown viscosity with protein content has been observed (Singh &Singh, 2010). The decrease in breakdown due to proteins has beenattributed to the stabilization of continuous matrix or strengthening ofthe links between the dispersed and continuous phase (Fitzgerald etal., 2003). The decrease in peak viscosity is associated with lower swell-ing of the starch granules.

3.3.8. Farinograhic characteristicsFlours from the majority of the cultivars showed water absorption

between 61 and 65%, however ranged between 58.1 and 68.4%.CBW38 showed the least water absorption while C306 showed thehighest. Farinograms of flours varying in dough strength are illustratedin Fig. 1b. Farinographic properties of flours are shown in Table 5a.Water absorption was positively correlated with flour protein content(r = 0.583, p ≤ 0.05) and negatively correlated with L* (r = −0.482,p ≤ 0.05) as well as sedimentation value of flour (r = −0.437,p ≤ 0.05). This indicated that light coloured flour had lower water ab-sorption as well as sedimentation value due to lower protein content.L* values of flours were negatively related to protein content. A negativecorrelation between L* values and protein content in corn flour has been

Pasting temperature(°C)

Farinographic properties

WA(%)

DDT(min)

DS(min)

DOS(BU)

67.7 ± 0.5c 58 ± 0.43 2 ± 0.16 13.8 ± 0.66j 14 ± 8a67.6 ± 0.4c 65 ± 0.46 6.7 ± 0.26 10.9 ± 0.72i 31 ± 13bc66.9 ± 0.5b 63 ± 0.44 1.5 ± 0.23 8.8 ± 0.12h 29 ± 11bc67.8 ± 0.4c 60 ± 0.45 5.5 ± 0.10 7.7 ± 0.10g 38 ± 13cd67.0 ± 0.5 63 ± 0.52 2 ± 0.10 7.6 ± 0.56g 24 ± 12ab66.9 ± 0.3b 62 ± 0.48 1.3 ± 0.22 7.6 ± 0.52g 38 ± 10cd66.9 ± 0.4b 64 ± 0.40 4.7 ± 0.17 7.4 ± 0.64g 37 ± 14d67.0 ± 0.6b 61 ± 0.38 1.7 ± 0.12 6.3 ± 0.60f 45 ± 11de67.7 ± 0.5c 61 ± 0.43 4.5 ± 0.12 5.3 ± 0.56e 57 ± 14e66.2 ± 0.5a 61 ± 0.43 4 ± 0.10 4.4 ± 0.32d 53 ± 13e67.7 ± 0.3c 63 ± 0.51 4.5 ± 0.18 3.7 ± 0.51c 72 ± 10f67.8 ± 0.5c 64 ± 0.78 3.5 ± 0.23 3.6 ± 0.44c 119 ± 24i66.2 ± 0.4a 62 ± 0.30 3.5 ± 0.12 3.5 ± 0.54c 124 ± 25i68.7 ± 0.4d 62 ± 0.76 1.5 ± 0.11 3.3 ± 0.42c 97 ± 16g68.5 ± 0.5d 65 ± 0.41 1.8 ± 0.23 2.8 ± 0.51b 142 ± 22i68.5 ± 0.4d 61 ± 0.44 1.7 ± 0.34 2.3 ± 0.45b 138 ± 20i66.2 ± 0.4a 68 ± 0.23 2.4 ± 0.12 1.9 ± 0.5a 110 ± 15h66.1 ± 0.5a 68 ± 0.30 3.7 ± 0.11 1.7 ± 0.4a 114 ± 15h

softening

a

bC306

0100200300400500600

0 4 8 12 16Time (mins)

Con

sist

ency

(B

U)

HD2888

0

100

200

300

400

500

600

0 4 8 12 16Time (mins)

Con

sist

ency

(B

U)

HD2643

0

100

200300

400

500

600

0 4 8 12 16

Time (mins)

Con

sist

ency

(B

U)

0

100

200300

400

500

600

0 4 8 12 16

Time (mins)

Con

sist

ency

(B

U)

CBW38

Fig. 1. Pasting curves (a) and Farinograms (b) of flours from different wheat cultivars.

69A. Kaur et al. / Food Research International 53 (2013) 63–72

observed (Sandhu, Singh, &Malhi, 2007).Water absorption also showedsignificant positive correlation with dry gluten (r = 0.467, p ≤ 0.05)and negative correlation with gluten score (r = −0.615, p ≤ 0.005).Dough development time ranged between 1.3 and 6.7 min, andNI5439 showed the lowest while HD2987 showed the highest doughdevelopment time. Dough development time showed negative and pos-itive relation to particles of size 1 to 45 μm and 50 to 100 μm, respec-tively. However, the correlation of dough development time withparticles of size 10 to 20 μm (r = −0.470, p ≤ 0.05) and 50 to100 μm (r = 0.468, p ≤ 0.05) was significant. Results revealed thatthe flours with higher proportion of fine flours required shorter timeto develop than flours with greater proportion of coarse particles maybe due to fast absorption of water. Majority of the cultivars showedthat dough development time ranged between 2 and 4 min. Doughstability ranged between 1.7 and 13.8 min, HD2888 showed the lowest.CBW38 showed the highest dough stability, quality number and theleast degree of softening. Dough stability showed significant correlationwith sedimentation values of bothmeal and flour (r = 0.806 and 0.794,p ≤ 0.005, respectively, Table 2). This indicated that thewheat cultivarswith higher dough stability had higher glutenins content since a signif-icant correlation of SDS sedimentation valuewith the glutenins contentand ratio of glutenins:gliadins has been reported earlier (Gil-Humaneset al., 2012). Dough stability was negatively correlated with flour

protein content (r = −0.677, p ≤ 0.05) and positively with Glu score(r = 0.575, p ≤ 0.05). A similar correlation between dough stabilityand flour protein content was reported earlier (Gil-Humanes et al.,2012). A negative correlation between dough stability and total gliadinscontent was reported earlier (Gil-Humanes et al., 2012; Singh et al.,2011). A significant correlation between sedimentation value with theglutenins content and ratio of glutenins:gliadins was also reported(Gil-Humanes et al., 2012). It could be inferred that flours with highertotal protein content may not always have higher dough stability. Adecrease in the overall dough strength and stability with the addi-tion of gliadins to base flours has also been reported (Fido, Bekes,Gras, & Tatham, 2002; Khatkar, Fido, Tatham, & Schofield, 2002).Dough stability showed negative correlation with wet as well asdry gluten (r = −0.603 and −0.635, respectively, p ≤ 0.005) andflour protein content (r = −0.677, p ≤ 0.005). This may be attributedto greater contribution of gliadin fractions in quantity to flour proteinsin comparison to glutenin fractions (Zhang et al., 2007). Most of flourswith higher proportion of small size particles showed higher doughstability while those that contained large size particles showed lower.

Degree of softening ranged between 14 and 142 BU, and majorityof the cultivars showed degree of softening between 40 and 120 BU.Degree of softening showed a positive correlation with dry gluten(r = 0.429, p ≤ 0.05) as well as flour protein content (r = 0.488,

70 A. Kaur et al. / Food Research International 53 (2013) 63–72

p ≤ 0.05). CBW38 showed the lower whereas PBW343 showed thehigher degree of softening. Flours with higher water absorptionshowed lower dough stability and high degree of softening. Interest-ingly flours with higher L* value showed higher dough stability andlower degree of softening. Flours with lower dough stability showedlower sedimentation value. C306, DL 788-7, DBW 17 and PBW 343cultivars having lower sedimentation value (36 to 38 ml) had lowerdough stability (1.9 to 3.5 min). Quality number ranged between 35and 150, and majority of the cultivars showed quality number rangedbetween 40 and 80. Flours with higher wet gluten, dry gluten andprotein content showed lower quality number and dough stability.A significant negative correlation of quality number with dry glutencontent (r = −0.567, p ≤ 0.05), wet gluten content (r = −0.543,p ≤ 0.05) and protein content was observed (r = −0.659, p ≤ 0.005).Therefore, wet gluten, dry gluten and protein content should be usedcarefully used while evaluating Indian wheat cultivars.

3.3.9. Dynamic rheology of dough and glutenAverage values of elastic modulus (G′) and viscous modulus (G″)

for the dough and gluten from flours from different wheat cultivarsare shown in Table 5b. The profiles of mechanical spectra showedthe typical structured systems, prevailing the solid like character,and exhibited a relatively high dependence of the viscoelastic moduliupon oscillatory frequency. The effect of frequency on the viscoelasticbehaviour of dough from different wheat cultivars showed significantvariation. Both moduli (G′ and G″) showed frequency dependencebehaviour i.e. increased with increase in frequency. Similar frequencydependence for G′ has been reported in earlier studies by Bohlin andCarlson (1980). G′ of dough from all the cultivars was greater than G″,indicating predominance of elastic character. CBW38 dough showedthe highest G′ and G″ and HD 2643 dough showed the lowest valuesfor these parameters. Both G′ and G″ were positively related to thesedimentation value hence both these parameters were dependenton protein content of the flour. The cultivars with greater dough sta-bility also showed higher values of both the moduli and lower tan δvalues. The lower tan δ values were indicative of a more elastic struc-ture, hence, CBW38 had the highest elasticity and C306 had the least.

G′ was greater than G″ of gluten measured during heating andcooling indicated the predominance of elastic behaviour amongst glutenfrom different wheat cultivars. The ratio of G″:G′ ranged from 0.37 (NI5439) to 0.52 (HD 2643 & PBW 343). G′ of gluten from all the cultivars

Table 5bG′ (elastic modulus), G″ (viscous modulus) of dough and gluten from different wheat cultiv

Cultivars Dough properties Gluten p

G′(Pa)

G″(Pa)

G′ 90 °C(Pa)

CBW38 17,057 ± 222l 5606 ± 145l 1337 ± 6HD2987 9114 ± 167h 3463 ± 123f 1428 ± 6HD2985 5311 ± 135e 2148 ± 98c 1543 ± 5HD2864 9671 ± 134i 3930 ± 124h 1115 ± 5PBW590 3805 ± 132c 1671 ± 89b 1132 ± 3NI5439 12,756 ± 189i 4745 ± 178j 1690 ± 4HI1563 4020 ± 180c 1653 ± 128b 1490 ± 3HD2967 6156 ± 148g 2845 ± 89e 1088 ± 4CBW39 4652 ± 187d 2126 ± 123c 372 ± 2PBW175 13,025 ± 128k 5064 ± 156k 1155 ± 5HD2643 2743 ± 120a 1424 ± 56a 900 ± 4HD2687 10,732 ± 178j 4474 ± 176i 909 ± 4DL788-2 3209 ± 114b 1437 ± 78a 1782 ± 6DBW17 5512 ± 128f 2209 ± 120c 1169 ± 5PBW343 3267 ± 87b 1719 ± 68b 752 ± 3DBW14 9184 ± 145h 3675 ± 126g 742 ± 3C306 5111 ± 120e 2290 ± 110d 855 ± 5HD2888 11,599 ± 150j 4927 ± 167j 613 ± 3

Means with similar letters in a column do not differ significantly (p ≤ 0.05).

decreased with the increase in temperature up to a range of 58.31 °Cto 63.49 °C followed by an increase in G′ with an increase in tempera-ture up to 90 °C. G′ and G″ at 25, 50 and 90 °C measured during heatingshowed significant positive correlationwith quality number, sedimenta-tion value, dough stability andnegativewith dry andwet gluten content.G′ of glutenmeasured at 70, 50 and 25 °C during cooling showed signif-icant correlation with sedimentation value, dough stability, qualitynumber and negatively with dry and wet gluten. G′ of gluten measuredduring heatingwas significantly positively correlatedwith GI. These cor-relations indicated that the differences in gluten from different cultivarsmay be due to glutenins content and of glutenins:gliadins. Sedimenta-tion value and dough stability has been reported to be correlated to ofglutenins content and glutenins:gliadins (Gil-Humanes et al., 2012).

3.4. Principle component analysis

To get a better overview on the results and to find relationship be-tween grain, flour, dough and gluten properties, principal componentanalysis (PCA) was performed. PCA of grain characteristics was carriedout separately. Loading plot for PC1 and PC of grain characteristics isillustrated in Fig. 2. PC1, PC2 and C3 accounted for 66.7% of cumulativevariance. PC1 contributed 31.5% variance and had TKW, a* value, diame-ter andGHI as themajor components, whilst PC2was responsible for 22%variance with Falling number, stirring number, L* value and protein con-tent being themain components. PC3 contributed 13% variancewith sed-imentation value being the main components. In the loading plot, GHIlocated opposite to L* value and flour recovery. While L* value and flourrecovery were located closely to each other and were positively related(Fig. 2b). Results revealed thatwheat cultivarswith lower GHI and higherL* value gave higher flour yield.Wheat cultivars with higher protein con-tent showed higher GHI and lower L* value. Wheat cultivars with lowerTKW and grain diameter showed higher GHI and a* value (redness).This indicated that cultivarswith higher TKWanddiameter had less com-pact structure that broke easily (as indicated by lower GHI) and resultedinto higher flour yield. The higher flour recovery observed in cultivarswith higher TKW and grain diameter may be attributed to their boldergrains and more endosperm/bran ratio.

PCA of grain, flour, dough and gluten characteristics was also carriedand the relationships between these properties are illustrated in Fig. 2b.The analysis revealed that PC1, PC2, PC3 and PC4 accounted for 64.5%cumulative variance. PC1 accounted for 31.2% variance with dough

ars measured at different temperature.

roperties

G″ 90 °C(Pa)

G′ 50 °C(Pa)

G″ 50 °C(Pa)

5g 246 ± 15e 4727 ± 130h 748 ± 37d5h 235 ± 14de 5673 ± 148k 978 ± 54fg4f 327 ± 21g 5780 ± 137k 912 ± 49f5e 216 ± 15c 4366 ± 113g 807 ± 45e6e 229 ± 18d 4459 ± 102g 753 ± 36d5i 329 ± 23g 6756 ± 158l 1159 ± 55h5h 274 ± 14f 5301 ± 143j 1014 ± 54g5d 218 ± 12c 4778 ± 123h 920 ± 55f0a 95 ± 5a 1319 ± 35a 288 ± 15a0e 263 ± 22f 5135 ± 122i 982 ± 41g0c 223 ± 13d 4183 ± 134f 1012 ± 43g8c 235 ± 14d 4631 ± 112 1229 ± 565j 205 ± 13c 4378 ± 87g 515 ± 22b5e 208 ± 15c 5029 ± 154i 818 ± 42e5c 139 ± 12b 3123 ± 112d 518 ± 25b0c 162 ± 11c 2940 ± 112c 504 ± 23b0b 156 ± 14c 3704 ± 123e 732 ± 35d0b 128 ± 12b 2314 ± 78b 635 ± 30c

71A. Kaur et al. / Food Research International 53 (2013) 63–72

stability, quality number, doughG′, doughG″, dough tan δ, glutenG′ andG″ as main contributors. PC2 accounted for 15.8% variance with stirringnumber, Falling number, pasting temperature, and proportion of parti-cles of different sizes were main components. Amongst particles of dif-ferent sizes, particle of size ranged between 10 to 45 and 100 to 200 μmshowedgreater contribution as compared to particles of other sizes. PC3account for 9.3% of variance, with a* value, b* value, GHI, TKW and graindiameter as main components. PC4 accounted for 8.3% variance, withGI, grain protein content and flour sedimentation value as major com-ponent. Dough stability was closely located to quality number andsedimentation value and a significant positive correlation betweenthese was observed. Dough stability was located opposite to water

First

Seco

nd C

ompo

nent

0-0.1-0.2-0.3-0.4

0.3

0.2

0.1

0.0

-0.1

-0.2

-0.3

-0.4

-0.5

Flour recoverySN (meal)

Sedim

Grain diameterTKW

L*-value

a

First C

Seco

nd C

ompo

nent

0.0-0.1-0.2

0.3

0.2

0.1

0.0

-0.1

-0.2

-0.3

Dry gluten

Wet gluten

PC (flour)

Particle size 200-300µm

Particle size 100-200µm

Particle s

tan70°C

tan 90

tan 50°C

tan dough

Pasting tem

P

DOS

DDT

Water absorption

SN(flour)

FN (flour)

b*-value (flour)

a*-value (flour)

Flour

SN (meal)

FN (meal)

Grain diameter

PC (grain)

TKW

GHI

b*-value (gr

a*-value (grain

b

Fig. 2. a. Loading plot for the first two components of grain characteristics. b. Loading plot for thTKW, thousand kernel weight; DS, dough stability; DDT, dough development time; FN, fallingnumber.

absorption, wet gluten and dry gluten. A significant negatively correla-tion of dough stabilitywith dry gluten, wet gluten andwater absorptionwas observed. Therefore it is not necessary that flours with higher wetand dry gluten contentwill always produce doughwith higher stability.Wet and dry gluten content should be used cautiously while evaluatingIndianwheat cultivars. Peak viscosity and breakdown viscosity were lo-cated closely to the sedimentation value and a positive relation betweenthese was observed. G′ and G″ of dough were positively correlated withsedimentation value, however, the relation of G′ and sedimentationvalue was stronger. Dough stability was closely located to G′ and G″ ofdough aswell as of glutenmeasured at 25, 70 and 90 °C. Dough stabilityshowed strong positive correlation with dough G′ and G″ and negative

Component

0.50.40.30.20.1.0

Falling number (meal)

entation value (meal)

Protein contentGHI

b*-value

a*-value

omponent0.30.20.1

Gluten score

Gluten index

ize 50-100µm

Particle size (20-45µm)

Particle size (10-20µm)

Particle size (1-10µm)

G G

G

G GG50

G

G

perature

eak time

Setback viscosityFinal viscosity

Breakdown viscosity

Peak viscosity

QN

DS

SV (flour)L*-value (flour)

recovery

SV (meal)ain)

L*-value (grain)

efirst two components of grain, flour, dough and gluten characteristics (G, grain; Fl, flour).number; PC, protein content; SV, sedimentation value; QN, quality number; SN, stirring

72 A. Kaur et al. / Food Research International 53 (2013) 63–72

correlation with tan δ. The correlation of dough stability with G′ and G″of gluten measured at 25, 70 and 90 °C was also significance. The culti-vars with greater dough stability also showed higher G′ and G″ andlower tan δ values. The lower tan δ values were indicative of a moreelastic structure, therefore, the cultivars that showed higher dough sta-bility had more elastic structure.

Dough stabilitywas correlated significantlywithpeak viscosity, break-down viscosity and final viscosity, which clearly indicated a significantcontribution of protein content. Pasting temperature was closely locatedto proportion of particles of size ranged between 1 and 45 μm. Pastingtemperature showed a significant positively correlation with the propor-tion of particles of size between 1 and 45 μm and negatively related toparticles of size between 50 and 200 μm size. Flours with greater L*value showed greater dough stability whereas lower stability for flourswith higher a* value and b* valuewas observed. A similar relationship be-tween quality number and a* and b* valuewas observed, however the re-lation of b* value with quality number was stronger. Flours with high L*values showed higher peak viscosity and breakdown viscosity whereasthosewith higher b* values showed lower peak and breakdown viscosity.

4. Conclusion

A wide diversity in physico-chemical, milling, pasting, dough andgluten properties amongst Indian wheat cultivars was observed. The cul-tivars with HMW subunits of 20 and 2 + 12 exhibited very weak doughstability of 1.7–1.9 min. Cultivars having 2 + 12 and 7 + 9 as well as5 + 10with 7 or 7 + 9hadweak dough stability of 2.8–4.4 minwhereasthose with subunits of 17 + 18 with 2 + 12 or 5 + 10 as well as of7 + 8 with 5 + 10 had strong dough stability between 8.8 and13.8 min. GHIwas negatively correlatedwith grainweight,flour recoveryand proportion of fine particles. GI did not show any significant relation-ship with flour protein content and dough stability however was nega-tively correlated with wet and dry gluten content. Dough stabilityshowed significant correlation with sedimentation values of both mealand flour, however negatively correlated with wet and dry gluten.Water absorption was positively correlated with flour protein contentand negatively correlated with sedimentation value. Flours with higherproportion of fine particles showed less dough develop time and hadhigher dough stability. G′ and G″ of gluten was positively correlatedwith quality number, sedimentation value and dough stability. The culti-vars with greater dough stability showed higher dough as well as glutenG′ and G″ and lower tan δ values, indicating presence of a more elasticstructure. GI, wet gluten and dry gluten content should be cautiouslyused while evaluating baking quality of Indian wheat cultivars.

Acknowledgements

Financial assistance from DBT and CSIR is acknowledged.

References

Axford, D. W. E., McDermott, E. E., & Redman, D. G. (1979). Note on the sodium dodecylsulfate test of breadmaking quality: Comparison of with Pelshenke and Zelenytests. Cereal Chemistry, 56, 582–584.

Ayoub, M., Fregeau-Reid, J., & Smith, D. L. (1993). Evaluation of the SDS-sedimentationtest for the assessment of eastern Canadian bread wheat quality. Canadian Journalof Plant Science, 73, 995–999.

Bekes, F. (2012). New aspects in quality related wheat research: 1. Challenges andachievements. Cereal Research Communications, 40, 159–184.

Bohlin, L., & Carlson, T. L. G. (1980). Dynamic viscoelastic properties of wheat flourdoughs: Dependence on mixing time. Cereal Chemistry, 57, 174–177.

Bonfil, D. J., & Posner, E. S. (2012). Can bread wheat quality be determined by glutenindex? Journal of Cereal Science, 56, 115–118.

Eckert, B., Amend, T., & Belitz, H. D. (1993). The course of SDS and Zeleny sedimenta-tion tests for gluten quality and related phenomena studied using the light micro-scope. Zeitschrift fur Lebensmittel Untersuchung und-Forschung, 196, 122–125.

Fido, R. J., Bekes, F., Gras, P. W., & Tatham, A. S. (2002). Effects of α-, β-, γ- and ω-gliadinson the dough mixing properties of wheat flour. Journal of Cereal Science, 26, 271–277.

Fitzgerald,M. A., Martin, M.,Ward, R. M., Park,W. D., & Shead, H. J. (2003). Viscosity of riceflour — A rheological and biological study. Journal of Agricultural and Food Chemistry,51, 2295–2299.

Fu, B. X., & Sapirstein, H. D. (1996). Procedure for isolating minomeric proteins andpolymeric glutenin of wheat flour. Cereal Chemistry, 73, 143–152.

Fustier, P., Castaigne, F., Turgeon, S. vL., & Biliaderis, C. G. (2007). Semi-sweet biscuitmaking potential of soft wheat patent, middle-cut, and clear mill streams madewith native and reconstituted flours. Journal of Cereal Science, 46, 119–131.

Gaines, C. S., Kassuba, A., & Finney, P. L. (1993). Using wire-cut and sugar-snap formulacookie test baking methods to evaluate distinctive soft wheat flour sets. Implica-tions for quality testing. Cereal Foods World, 41, 155–161.

Gil-Humanes, J., Piston, F., Rosell, C. M., & Barro, F. (2012). Significant down-regulationof γ-gliadins has minor effect on gluten and starch properties of bread wheat. Journalof Cereal Science, 56, 161–170.

Khatkar, B. S., Fido, R. J., Tatham, A. S., & Schofield, J. D. (2002). Functional properties ofwheat gliadins. I. Effects onmixing characteristics and breadmaking quality. Journal ofCereal Science, 35, 299–306.

Laemmli, U. K. (1970). Cleavage of structural protein 411 during the assembly of thehead of bacteriophage T4. Nature, 227, 680–685.

Lafiandra, D., D'Ovidio, R., Porceddu, E., Margiotta, B., & Colaprico, G. (1993). New datasupporting high Mr Glutenin subunit 5 as the determinant of quality differencesamong the pairs 5 + 10 vs. 2 + 12. Journal of Cereal Science, 18, 197–205.

Loh, J. (1992). The effect of shear rate and strain on the pasting behaviour of foodstarches. Journal of Food Engineering, 16, 75–89.

MacRitchie, F., du Cros, D. L., & Wrigley, C. W. (1990). Flour polypeptides related towheat quality. Advances in Cereal Science and Technology, 10, 79–145.

Naeem, H. A., Paulon, D., Irmak, S., & MacRitchie, F. (2012). Developmental and envi-ronmental effects on the assembly of glutenin polymers and the impact on grainquality of wheat. Journal of Cereal Science, 56, 51–57.

Nemeth, L. Y.,Williams, P. C., & Bushuk,W. (1994). A comparative study of the quality of softwheat from Canada, Australia and the United States. Cereal Foods World, 39, 691–700.

Numfor, F. A., Walter, W. M., & Schwartz, S. J. (1996). Effect of emulsifiers on the phys-ical properties of native and fermented cassava starches. Journal of Agricultural andFood Chemistry, 44, 2595–2599.

Payne, P. I. (1987). Genetics of wheat storage proteins and the effect of allelic variationon bread-making quality. Annual Review of Plant Physiology, 38, 141–153.

Payne, P. I., & Lawrence, G. J. (1983). Catalogue of alleles for the complex gene loci,Glu-A, Glu-B and Glu-D, which account for the high-molecular-weight subunitsof glutenin in hexaploid wheat. Cereal Research Communications, 11, 29–35.

Popineau, Y., Cornec,M., Lefebvre, J., &Marchylo, B. (1994). Influence of highMr glutenin sub-units on glutenin polymers and rheological properties of glutens and gluten subfractionsof near-isogenic lines of wheat Sicco. Journal of Cereal Science, 19, 231–241.

Ragaee, S., & Aal, E. M. A. (2006). Pasting properties of starch and protein in selectedcereals and quality of their food products. Food Chemistry, 95, 9–18.

Sandhu, K. S., Singh, N., & Malhi, N. S. (2007). Some properties of corn grains and theirflours I: Physicochemical, functional and chapati-making properties of flours. FoodChemistry, 101, 938–946.

Shewry, P. R., Halford, N. G., Tatham, A. S., Popineau, Y., Lafiandra, D., & Belton, P. S. (2003).The high molecular weight subunits of wheat glutenin and their role in determiningwheat processing properties. Advances in Food and Nutrition Research, 45, 219–302.

Singh, N. K., & Shepherd, K. W. (1985). The structure and genetic control of a new classof disulphide-linked proteins in wheat endosperm. Theoretical and Applied Genetics,71, 79–92.

Singh, S., & Singh, N. (2010). Effect of debranning on the physico-chemical, cooking,pasting and textural properties of common and durum wheat varieties. FoodResearch International, 43, 2277–2287.

Singh, S., Singh, N., & MacRitchie, F. (2011). Relationship of polymeric proteins withpasting, gel dynamic- and dough empirical-rheology in different Indian wheatvarieties. Food Hydrocolloids, 25, 19–24.

Sissons, M. J., Ames, N. P., Hare, R. A., & Clarke, J. M. (2005). Relationship betweenglutenin subunit composition and gluten strength measurements in durumwheat. Journal of the Science of Food and Agriculture, 85, 2445–2452.

Slaughter, D. C., Norris, K. H., & Hruschka, W. R. (1992). Quality and classification ofhard red wheat. Cereal Chemistry, 69, 428–432.

Wieser, H., & Kieffer, R. (2001). Correlations of the amount of gluten protein types tothe technological properties of wheat flours determined on a micro-scale. Journalof Cereal Science, 34, 19–27.

Zhang, P., He, Z., Chen, D., Zhang, Y., Larroque, O. R., &Xia, X. (2007). Contribution of commonwheat protein fractions to dough properties and quality of northern-style Chinesesteamed bread. Journal of Cereal Science, 46, 1–10.