Predicting cookie wheat germplasm performance
Compared to the large effort spent developing Brazilian bread wheat cultivars, relatively few soft wheat cultivars for cookie flour were released in this country in the recent years. The objective of this study is to propose a model to predict wheat cultivars with improved manufacturing quality for the cookie industry while maintaining production for the growers. A database was compiled originally with 1674 entries with field, milling and flour quality parameters from the year 2000 to 2008 crop seasons. The critical specifications of 14 commercial cookie flours were compared and it was determined that the variables farinograph water absorption appeared in 14 out of 41 specifications (34.1%), alveograph strength appeared in 13 out of 41 specifications (31.7%), wet gluten appeared in 11 out of 41 specifications (26.8%), alveograph tenacity appeared in two out of 41 specifications (4.9%), and alveograph dough extensibility appeared in one out of 41 specifications (2.5%). Using frequency percentages as model coefficients a Brazilian Cookie Wheat Score Model was proposed:<br />BCWS =ABS × 0.341 + W × 0.317 + WG × 0.268 + P × 0.049 + L × 0.025. The ideal score for a wheat genotype to be classified as cookie wheat for the Brazilian market is within the optimum interval from 56.1 to 81.2. To validate this model and its proposed interval, 277 wheat entries from the 2008 crop year were tested under the following conditions: first, wheat genotypes that yielded less than the average of bread wheat genotypes were discharged; second, wheat genotypes without the full set of values for the model variables were discharged. Twenty wheat genotypes, out of 277, were within the optimum interval and were proposed as wheat genotypes to produce cookie flour. The validation results indicated that, using the BCWS Model, along with the established conditions, a wheat breeder will have 75% chance of finding a potential cultivar with acceptable cookie functionality from a set of experimental lines.
