Reliability of gluten-related small-scale tests to estimate dough viscoelasticity and bread loaf volume

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International Gluten Workshop, 11th; Beijing (China); 12-15 Aug 2012

International Gluten Workshop, 11th; Beijing (China); 12-15 Aug 2012

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  • 1. 11Th International Gluten WorkshopAug 12-15, 2012. Beijing, China Gluten protein network Reliability of gluten-related small-scale tests to estimate dough viscoelasticity and bread loaf volume Roberto J Peña et al. CIMMYT Acknowledgements: Carlos Guzman Nayeli Hernandez Gabriel Posadas Wheat Quality Laboratory CIMMYT
  • 2. OutlineIntroduction:Bread making quality attributes; breedingscheme and screening for bread making qualityObjectivesComparison of glutenin-related small-scale testsRapid small-scale test studyM&MResults & DiscussionSummary
  • 3. Gluten quantity and quality arethe main grain factors defining:The processing performance ofthe bread making dough • Dough mixing time; stability; tolerance to overmixing • Dough elasticity; viscosity; handling propertiesThe quality of the final bakingproduct • Bread volume; crumb texture; freshness retention time
  • 4. CIMMYT wheat program main breeding objective is tocombine high yield potential, disease resistance, anddesirable end-use quality attributes Glu-1New crosses: Parental lines selected to combine MAS Glu-3 Sec-1  x xhigh yield, disease resistance and desirable quality Gli-1(grain hardness, gluten proteins, starch)Breeding activities Generation Yellowness Hardness (NIR), protein % andScreening: Yield and disease resistance F1-F2 Sedimentation(60 -80 thousand lines) F3-F4 NIRS x Discard  SelectScreening: Yield-Disease resist.-Quality F5(4 -6 thousand lines) F6 Mixographic TypeScreening: Yield-Disease resist..-Quality F7 x Alveograph(2 - 3 thousand lines) F8 x Tenacious  gluten xScreening: Yield-Disease resist..-Quality F9(>1000 lines from 3-4 environments) F10 x Weak gluten baking  W >300Elite Yield trials/ C Int. Nurseries. Quality(500-1000 lines from 3-4 environments)Yield trials in commercial fields/Quality  W >350(10-20 lines/6-8 fields)
  • 5. SDS-PAGE of gluten protein Glu-1• We examine the influence of Glu-1/Glu- Glu-B2 3/Gli-1 alleles on dough viscoelasticity and bread making quality Glu-B3• Crosses are made to achieve best allelic combinations to develop wheat varieties for diverse uses b d d b f f b f b i,k d• Contribution of LMW-glutenins (GLU-B3) to Gli-B1 wheat quality properties:-Dough mixing quality: i, d, b≥, g, f, h, >b->J-Dough extensibility: g, f, i≥, b, h, , d>b->J-Dough strength: i, g, f, b≥ h , d>b->J
  • 6. Instruments/tests commonly used in breeding to assess breadmaking quality-related parameters: • Mixograph. Dough mixing properties (dough development time; stability; tolerance to over mixing • Alveograph. Dough viscoelasticity (dough strength, and tenacity/extensibility ratio) • Bread baking test. Actual baking performance (loaf volume and crumb texture)These methods are time-consuming and therefore have limiteduse in screening for quality at early stages of breeding.
  • 7. Sodium dodecyl sulfate-Sedimentation(SDS-S)The SDS-S test is well accepted,particularly at early stages ofbreeding, as a reliable parameter toscreen for gluten strength in Common& Durum wheat.Determines the volume of the floursuspended in lactic acid-SDS solutionIt is a fair-to-good estimate of glutenstrength (and extensibility?)The SDS-value is influenced by bothprotein quantity and quality, andenvironmental conditions
  • 8. The relationship between SDS-sedimentation and doughstrength parameters varies across environments. We need abetter screening tool 0.8 Elite lines under different managements/environment conditions ( Y2009-10 n=90) SDSS vs. Mix. Time SDSS vs. W SDSS vs. P/L 0.6 0.4 0.2 0 Flat (melgas) Zero Till Beds, Red Irrig Beds, Red Drip Beds, Heat Irrgi -0.2 Correlation coefficients significance: r> 0.34 -0.4
  • 9. Glutenin swells in dilute acid and SDS solutions.Some glutenin-related small-scale methods showing potentialto screen for bread making quality:•SDS-Sedimentation test (SDS-S). The insoluble glutenin expands as a highly hydrated aggregate that contributes to the volume of the sediment.•Lactic Acid Retention Capacity (LARC). The highly hydrated insoluble glutenin is trapped in the centrifuged pellet, and is the main factor defining the weight gain of the tested flour•Swelling index of glutenin (SIG). The flour is suspended in alcohol- lactic acid. The swelling (swollen flour wt / flour wt) is directly related to the quantity and the quality of mainly the insoluble glutenin (Wang & Kovacs 2002; Weegels et al. 1996)
  • 10. Objectives1. To scale-down the LARC method, attempting to increase the throughput of the test2. To compare the three small-scale tests (SDS-S; LARC; SIG) with respect to their relationship with: • Dough mixing properties; dough strength and extensibility; and bread loaf volume • Compare the relationship of the small-scale tests under different environmental conditions
  • 11. MaterialsWheat advanced lines (242); various elite yield trials (CIMMYT, Mexico Y. 2010-11)No N-fertilizer limitationsTesting conditions: Optimum irrigation; Drip reduced irrigation;Reduced irrigation; Zero-tillGenotypes represented wide variability in quality traits (grain hardness; dough viscoelasticity; and bread making loaf volume.MethodsProtein (NIRS); Mixograph (DDT and % Torque); Alveograph (W and P/L); and breadloaf volume, according to AACC methods-SDS-sedimentation test (FLRSDS-S), ml/1g flour, according to Peña et al. (1990)-Lactic acid retention capacity (LARC), %, AACC method 56-11 (& scaled-downversion)-Swelling index of glutenin (SIG), weight of residue/40 mg flour, according to Wang andKovacs (2002)
  • 12. Lower cost and higher Description Method AACC Scaled-down (56-10 & 56-11) LARCthroughput by 5g flour/50 ml 0.3g flour/1.5 mlscaling-down the AACC Cost 100% 0.5x of AACCLARC method Samples 100% 2x of AACC tested AACC method Lactic Acid SRC, % 200 y = 1.3795x - 45.582 R²= 0.9359 180 160 140 120 100 80 80 90 100 110 120 130 140 150 160 170 Scaled-down method
  • 13. Relationship small-scale tests vs. dough parameters1.00 Low protein: 8.8-12.3% (n = 187)0.800.600.40 Significant0.20 (α = 0.05)0.00 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL-0.20 1,00-0.40 1.00 0,80 0,60 High protein: 12.6-17.0% (n = 57)0.80 0,400.60 Significant 0,20 (α = 0.05)0.40 0,00 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL0.20 -0,200.00 -0,40 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL-0.20 -0,60-0.40 -0,80 FLRSDS Lactic acid, Ret% SIG
  • 14. Relationship small-scale tests vs. dough parameters1.00 R> 38, significant Optimun Irr. (n=104) (α = 0.05)0.500.00 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL-0.501.00 R> 40, significant Drip Red. Irr. (n=27)0.50 (α = 0.05)0.00 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL-0.50 1,001.00 R> 40, significant Reduced Irr. (n=31) 0,80 (α = 0.05)0.50 0,600.00 0,40 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL-0.50 0,20 1.00 Zero-till (n=49) 0,00 R> 40, significant 0.50 (α = 0.05) GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL -0,20 0.00 -0,40 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL-0.50 -0,60 -0,80 FLRSDS Lactic acid, Ret% SIG
  • 15. Relationship small-scale tests vs. dough parameters1.00 FLRSDS Lactic acid, Ret% SIG FLRProt0.800.600.400.200.00 GRNHRD FLRPRO MIXTIM %TQ*MIN. ALVW ALVPL LOFVOL (n = 244)-0.20 Red line shows significant R values (α = 0.05)
  • 16. Over all observed quality-predicting value: SIG>LARC>SDS-S The SIG test is difficult to perform; requires consistent, one- single, decanting step (flour-gel residue tends to flow down) The scaled-down LARC test is very simple and easy to perform. But, higher throughput is desirable. Sample, 1st Mix 2nd Mix Centri Total Observ. g solvent time, solvent time, fuge testing min min time, time, min minLARC 0.3 LA 5 - - 2 10 EasySIG 0.04 Water 10 Isopr-LA 10 5 30 Decanting is difficult (one short movement)
  • 17. NIRS-based molecular spectroscopy LARC % 160.0Preliminary data on NIRS 150.0 R²= 0.8519calibration, using 50-70 140.0 130.0 LARC %contrasting lines (samples 120.0spectra), indicate that 110.0 100.0reliable calibrations for LARC 90.0and SIG are feasible. 80.0 90.0 100.0 110.0 120.0 130.0 140.0 150.0 160.0 170.0 FT-NIRS (Antharis) % SIGNo validation has been 6.5 R²= 0.8391performed yet 6 5.5 SIG 5More work is needed. 4.5 4 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 FT-NIRS (Antharis) %
  • 18. Summary• The efficiency of SDS-Sedimentation to predict dough strength-related parameters varies with different environmental conditions• SDS-S is still generally efficient but LARC and SIG have shown better relationship with dough-strength parameters and bread making• SIG showed better prediction value of bread making quality under various different environment and protein levels.• However, the single decanting step of the SIG test is difficult to master• LARC is easy to handle, although the number of samples /day is not as large as what can be handle with SDS-S• Attempts to develop NIRS calibration for SIG and LARC are highly promising
  • 19. Thank you