Cereal Chem. 74(4):489-494Undeveloped wheat dough is essentially wheat flour that has become fully hydrated without being deformed. The rheological properties of this material were compared to dough (developed dough) made using the standard method involving a farinograph. Flow behavior of undeveloped and developed dough samples made from hard and soft wheat flours were tested using creep tests, frequency sweep oscillatory tests, and temperature sweep oscillatory tests. All experiments showed that the undeveloped dough requires less resistance for deformation than developed dough. The differences are due to the energy input received by the developed dough and the influence of this factor in forming the protein matrix associated with developed dough. To attain a comparable state as the dough made in the farinograph, an energy input must be applied to the undeveloped dough material. Understanding the differences between undeveloped and developed dough may lead to new products, equipment, and processes in the bakery industry.Traditionally, dough is made by combining flour, water, and energy through mixing. The addition of sufficient mechanical energy provides the distribution and hydration of flour particles, allowing the formation of a continuous protein matrix (holding starch and other components). The dough thus formed, a developed dough, has a unique viscoelastic behavior (Schofield and Scott Blair 1932) which is a result of the complex reactions between the sulfhydryl (S-H) and disulfide (S-S) bonds found in gluten (Eliasson and Larsson 1993). Undeveloped dough is a homogeneous, fully hydrated wheat flour where the energy input phase of dough development has not been initiated .The rheological characterization of wheat flour dough is essential. It gives valuable information concerning the quality of the raw materials, the textural characteristics of the finished products and properties needed for the design and development of new equipment. Published literature on dough rheology is very extensive, and various summaries have been published in recent years (Faridi

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The robustness of a microbial growth model must be assessed before the model can be applied to new food matrices; therefore, a methodology for quantifying robustness was developed. A robustness index (RI) was computed as the ratio of the standard error of prediction to the standard error of calibration for a given model, where the standard error of calibration was defined as the root mean square error of the growth model against the data (log CFU per gram versus time) used to parameterize the model and the standard error of prediction was defined as the root mean square error of the model against an independent data set. This technique was used to evaluate the robustness of a broth-based model for aerobic growth of Escherichia coli 0157:H7 (in the U.S Department of Agriculture Agricultural Research Service Pathogen Modeling Program) in predicting growth in ground beef under different conditions. Comparison against previously published data (132 data sets with 1,178 total data points) from experiments in ground beef at various experimental conditions (4.8 to 45 degrees C and pH 5.5 to 5.9) yielded RI values ranging from 0.11 to 2.99. The estimated overall RI was 1.13. At temperatures between 15 and 40 degrees C, the RI was close to and smaller than 1, indicating that the growth model is relatively robust in that temperature range. However, the RI also was related (P < 0.05) to temperature. By quantifying the predictive accuracy relative to the expected accuracy, the RI could be a useful tool for comparing various models under different conditions.

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