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As discussed, the gluten network is largely responsible for the unique biophysical properties of dough, a balance between extensibility and elasticity. Highly viscous doughs are readily extended when stretched whereas elastic doughs resist extension and exhibit elastic recoil when the stress is relaxed (Chapter 8). Highly elastic doughs are referred to as strong and are preferred for making leavened bread (Figure 1.22). This is because the gas released during fermentation (proofing) is captured in bubbles, allowing the dough to rise. The protein network is then denatured by baking, giving a light porous structure to the bread. By contrast, biscuit production requires weak but extensible doughs that can be spread out into an even layer without recoil after rolling. Intermediate strength doughs can be used to produce steamed bread, chapatis, and noodles (Figure 1.22), but puffed breakfast cereals require strong wheat to prevent disintegration when pressure is released after cooking. Flaked and shredded products are made from wheats with weak gluten similar to those used for biscuits (Blackman and Payne 1987; Lin et al. 1990).

Figure 1.22 The relationships between grain protein content, dough strength, grain texture, and the quality of bread wheat for various products.

Source: Adapted from Peña (2002), Uthayakumaran and Wrigley (2017), and Moss (1973).

The cooking quality of pasta made from durum wheat is mainly determined by the ability to absorb water while retaining firmness and shape and without becoming sticky (Sarrafi et al. 1989). Both the processing and cooking of pasta are, therefore, dependent on strong gluten. Tenacious doughs have high initial resistance to extension but break after only a relatively small distance; they are often described as short and their suitability is limited to some domestic uses (Guzman et al. 2016). The role of gluten proteins in determining dough rheology and end‐use functionality has led to the importance of grain protein concentration and protein quality in the marketing and classification of wheat (e.g. CGC 2020).