Most of our knowledge about the 'genetics of quality' derives from two different experimental approaches: i) direct measurements of quality traits on samples with systematically altered chemical compositions; and, ii) relating quality and chemical composition/genetics of large sample populations using statistical methods. An overview on the recent achievements of these two approaches will be given illustrating the advantages/limitations of small- and micro-scale methodology and in vitro reconstitution/incorporation methods in basic research and in different applications as well as introducing three prediction procedures for dough properties (Protein Scoring System; PSS), loaf volume (PQI) and water absorption. The PSS model relates the individual and interactive contributior of high molecular weight (HMW) and low molecular weight (LMW) glutenin alleles to specific dough parameters, predicting the genetic potential of dough strength and extensional properties of dough of wheat flour with 12% proteincontent and with the ratios of glutenin to gliadin and HMW to LMW glutenin subunits (GS) of 1.0 and 0.2, respectively. The most advanced version of the model is capable of considering the effects of expression levels of different storage protein genes,allowing prediction oactual dough parameters. The input of this model is the allelic composition and quantitative protein composition (including UPP%), while the output provides a good estimate of actual dough strength and extensibility of a given sample (r~2>0.85 and r~2>0.75, respectively). Further applications of the models are also useful in blending formulations and in combining data to predict the technology specific bread-making potential (PQI) of samples using a nonlinear model.
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