|MadSci Network: Microbiology|
I would say very little. Bread in general is a very nutrient rich food source for molds to grow, especially if there is enough moisture in the bread to support growth. The main nutrients needed for the growth of the mold would be carbon sources for energy such as carbohydrates and possibly proteins, nitrogen sources for protein production and DNA metabolism probably from the proteins (only needed in very small amounts), and water. Some trace vitamins, minerals etc. would also be there. The gluten in bread is basically the stretchy material which holds the dough together. Even if the gluten content was very low and you had a flat bread, there would still be enough protein from other proteins in bread, such as albumins and globulins to support the nitrogen requirments of many types of molds.
Hope that answers your question.
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