|MadSci Network: General Biology|
Hi! This is an interesting question as I had never noticed the shrinkage. So I am assuming that you have been doing some actual measurements? The factors that may be involved in this shrinkage would be the moisture content and the "structure" of the bread which is provided by the protein gluten. The amount of heat added would also affect this change -- and would thus be different if different sizes and weights of bread were put into a toaster. Cheers.
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