Polymerization bread

Bread is made from water plasticized wheat flour, which in turn consists of ground-up wheat seeds. Dry flour consists of approximately 12% of protein, 87% of starch, and approximately 1% of everything else, such as minerals and salts. Since both the protein and the starch are polymeric, bread dough and... 

Suppose we start with a starch-rich meal, say one containing a lot of pasta or bread. The digestion of starches begins in the mouth. Saliva contains an enzyme, salivary amylase (aka ptyalin), which catalyzes the conversion of starch to simple sugars such as glucose. This process is completed in the small intestine under the influence of other enzymes in the amylase class. This completes the first phase of carbohydrate catabolism the conversion of complex, polymeric carbohydrates (e.g., starches) to their simple monomeric units, the sugars. 

To make a solid foam we start from a liquid foam and induce solidification. This can be achieved by a chemical polymerization (Styrofoam), by lowering the temperature (pumice stone or a souffle), or by increasing the temperature to induce a structural transition (baking of bread). Porous solids can appear as solid foams because of their low density and their high content of gas. The difference between the two is that in a porous solid we have a bicontinuous structure while the individual cavities in a foam are closed. This is an important difference because porous solids tend to adsorb liquids due to capillary effects and then completely change their properties. 

Both polymeric and some biological reactors often contain non-Newtonian liquids in which viscosity is a function of shear rate. Basically, three types of non-Newtonian liquids are encountered power-law fluids, which consist of pseudoplastic and dilatant fluids viscoplastic (Bingham plastic) fluids and viscoelastic fluids with time-dependent viscosity. Viscoelastic fluids are encountered in bread dough and fluids containing long-chain polymers such as polyamide and polyacrylonitrite that exhibit coelastic flow behavior. These... 

Mathematical Characterization of the Compressive Stress-Strain Relationship of Polymeric Foams, Breads and Cakes... 

Foams are closely related to emulsions. In foams, the dispersed phase is not an oil or water, but it is a gas. One can use similar techniques for making foam and for making emulsions, and some of the properties are comparable. Foams are ubiquitous as well of course, the foam on beer is well known, but bread is a foam as well, as are ice cream, whipped cream, expanded polystyrene or styrofoam (which is a solid polymeric matrix with a large volume fraction of gas bubbles in it), and polyurethane foam, used, for example, for making mattresses. 

Gupta, R. B., K. Khan, and F. MacRitchie. 1993. Biochemical basis of flour properties in bread wheats. I. Effect of variation in quantity and size distribution of polymeric proteins. Journal of Cereal Science 18 23-44. 

Viscoelastics No unique Saliva, nearly aU-biological fluids, concentrated tomato soup, bread dough, many polymeric solutions... 

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