Dough quality

However, recent publications are indicating a switch to describing dough quality by dough rheology, including extensional rheometry. Some of these rheology-based methods are summarized below. 

Extensional rheometry represents an increasingly important research tool fc - our understanding of dough quality. Results are of interest to both the food and agricultural industries. 

Dough quality and strength in breakmaking depends on the gluten proteins in wheat (2). Hyder et al. (21) demonstrated by starch gel electrophoresis that the isoelectric protein fraction... 

Lawrence, G. J., H. J. Moss, K. W. Shepherd, and C. W. Wrigley. 1987. Dough quality of biotypes of 11 Australian wheat cultivars that differ in high-molecular-weight glutenin subunit composition. Journal of Cereal Science 6 99-101. 

Fig. 15.29. Extensograms of a normal (I) and weak dough (II). For quality assessment the following parameters are determined resistance to extension, height of the curve at its peak (B-C) given in extensogram units (EU) extensibility, abscissa length between A-C in mm extension area (A-B-C-A, cm ) is related to energy input required to reach the maximum resistance extensogram number (overall dough quality) is the ratio of extension resistance to extensibility...

As discussed in Chapters 10 and 11, rheology can be very sensitive to the microstructure of liquids. For example, the viscosity of entangled polymer melts depends on molecular weight to the 3.4 power, T]o Ml . Equilibrium creep compliance is very sensitive to molecular weight distribution. The yield stress and low frequency G are good indicators of the flocculation state of colloids. Extensional viscosity can be an important indicator of bread dough quality (Padmanabhan, 1993). 

AWB hard wheat is made up of specific hard-grained white wheat varieties selected for superior milling performance and excellent dough quality. It is segregated at a guaranteed minimum protein level of 11.5%. Suited to the production of a wide range of baked products including European-style pan and hearth breads, Middle Eastern flat breads, and Chinese steamed products such as mantou and pao, as well as Chinese-style yellow alkaline noodles. 

Flour Bleaching Agents and Bread Improvers. Freshly milled flour contains carotenoid pigments that cause the flour to have a yellow color. In addition, when the flour is made into dough the product is sticky and unmanageable. As the flour ages, a natural process takes place which turns the flour white and improves its baking qualities. Because the natural process takes quite a bit of time, additives are used to speed up the process. 

A great deal of effort has been made to investigate the role of xylans in bread making. Reviews on cereal xylans [39,41,118] have shown that the xylan component is primarily responsible for the effects on the mechanical properties of the dough as well as the texture and other end-product quality characteristics of baked products. 

Caballero PA, Gomez M and Rosell CM. 2007. Improvement of dough rheology, bread quality and bread shelf-life by enzymes combination. J Food Eng 81 42—53. 

Flour treatment agent (FTA) Glazing agent Substance (other than emulsifiers) which are added to flour or dough to improve baking quality Substance which, when applied to the external surface of a foodstuff, imparts a shiny appearance or provides a protective coating... 

Extrusion parameters, such as basket temperature, extrusion rate, and die design, can be adjusted to suit a particular formulation and granule size. This is an empirical process based on experience. Extrusion characteristics represent an intimate interplay between press parameters and dough properties, the latter predominating. What is wanted is maximum production rate of a smooth, dense, homogeneous strand of these qualities, smoothness is perhaps most sensitive to extrusion conditions. 

While these methods can provide useful information for determining the functional performance of Ingredients used in food, the criteria for quality must be established on the final product thus, dough must be baked into bread and meat analogues cooked and these foods subjected to organoleptic evaluation for texture. 

A bacterial maltogenic amylase preparation has unique qualities as an antistaling agent. Additionally, it cannot be overdosed, which means that there is no risk of obtaining sticky doughs and a gummy cmmb structure. 

There are numerous examples where food extensional properties are relevant from the product quality perspective - some obvious examples include the extensibility of doughs, stretching of Mozzarella or Pizza cheese melts, extrusion-cooking of cereals, flow of honey and treacle. Overall, dough products have received the most attention. The importance of extensional viscosity in food processing has been reviewed by Escher (44 and references therein). 

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