dc.contributor.advisor Labuschagne, M. T.
dc.contributor.advisor Van Biljon, A.
dc.contributor.advisor Otto, W. M.
dc.contributor.author Miles, Christina Wilhelmina
dc.description.abstract English: The main objective of this research was to determine relationships between selected mixogram parameters and grain, milling, rheological, baking qualityrelated and baking quality characteristics to assist wheat breeders in selecting earlier for desirable primary rheological and baking criteria as required by the Wheat Technical Committee in South Africa when only small grain/flour samples are available. Highly significant differences were observed from combined ANOVA’s among genotypes, environments and GXE interactions for most of the measured characteristics. Genotypes contributed significantly to the variance in hectolitre mass, thousand kernel mass, kernel diameter, break flour yield, flour yield, farinogram water-absorption, alveogram dough stability (P-value), alveogram dough distensibility (L-value), alveogram P/L-value, alveogram dough strength, SDS-sedimentation volume, wet gluten content, loaf volume and loaf volume expressed on a 12% protein basis. Environments had a larger effect on hardness index, vitreous kernels, grain protein content, falling number, flour protein content, flour colour, flour colour expressed on a 76% flour yield basis and mixogram water-absorption. Highly significant positive and negative correlations were observed between the selected mixogram parameters (as determined by Mixsmart software) and grain, milling, rheological, baking quality-related and baking characteristics. Multiple stepwise regressions indicated mixogram parameters to be poorly predictable by grain and milling characteristics. Mixogram parameters (total area and tailheight) were identified as selection criteria to assist wheat breeders in selecting earlier for acceptable primary rheological and baking criteria of importance during cultivar release in South Africa. en_ZA
dc.description.abstract Afrikaans: Die doel van die studie was om te bepaal watter broodkoringkwaliteitseienskap/ pe, bepaalbaar op ‘n klein monster koring/meel, vir koringtelers tot hulp kan wees om vroegtydig koringlyne uit te skakel wat tydens die finale evaluasie vir cultivar-vrystelling ongewenste primêre reologiese- en bakeienskappe mag openbaar en dus afgekeur gaan word. Gesamentlike variansie analises het hoogs betekenisvolle verskille aangedui vir kultivars, omgewings en genotipe x omgewingsinteraksies vir die meeste eienskappe. Genotipes was hoofsaaklik verantwoordelik vir die variasie in hektolitermassa, duisendkorrelmassa, korreldeursnee, breekmeel-opbrengs, meelekstraksie, farinogram waterabsorpsie, alveogram deegstabiliteit (Pwaarde), alveogram deegelastisiteit (L-waarde), alveogram P/L-waarde, alveogram deegsterkte, SDS-sedimentasie volume, nat gluten inhoud, broodvolume en aangepaste broodvolume. Omgewing het ‘n groter invloed gehad op hardheid, horingagtige korrels, graanproteïeninhoud, valgetal, meelproteïeninhoud, meelkleur, aangepaste meelkleur en waterabsorpsie soos op ‘n miksograaf bepaal. Hoogs betekenisvolle positiewe en negatiewe korrelasies tussen geselekteerde miksogram-eienskappe en graan-, maal-, reologie-, bakverwante en bak-eienskappe is waargeneem. Stapsgewyse meervoudige regressies het aangedui dat miksogram-eienskappe swak voorspel word deur graan- en maal-eienskappe. Miksogram-eienskappe, bepaal met Mixsmart sagteware, is geïdentifiseer wat koringtelers kan help in vroeë selektering van verlangde primêre reologiese- en bak-eienskappe (farinogram waterabsorpsie, alveogram deegsterkte, alveogram P/L-waarde en aangepaste broodvolume), soos verlang deur die Koring Tegniese Kommittee tydens die kultivar-vrystellingsproses in Suid-Afrika. af
dc.subject Dissertation (M.Sc.Agric. (Plant Sciences: Plant Breeding))--University of the Free State, 2010 en_ZA
dc.subject Wheat en_ZA
dc.subject Wheat -- Quality en_ZA
dc.subject Wheat -- Milling en_ZA
dc.subject Cultivar release process en_ZA
dc.subject Mixsmart en_ZA
dc.subject Baking en_ZA
dc.subject Rheological en_ZA
dc.subject Milling en_ZA
dc.subject Grain en_ZA
dc.subject Bread wheat en_ZA
dc.title Mixogram parameters and their relationship to bread wheat quality characteristics en_ZA