Are you asking how bread get's it's crusty flavor, or how to get a bready/crusty flavor in your beer?
In bread it is from the Maillard reaction; a chemical reaction between an amino acid and a reducing sugar, usually requiring heat. It is vitally important in the preparation or presentation of many types of food, and, like caramelization, it is a form of non-enzymatic browning. Basically the sugars on the crust begin to carmelize in the heat.
In beer there are certain grains that impart a bready flavor, such as Victory Malt
SOme yeast can also produce those esters that remind people of bread as well...
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Revvy's one of the cool reverends. He has a Harley and a t-shirt that says on the back "If you can read this, the bitch was Raptured. - Madman
I gotta tell ya, just between us girls, that Revvy is HOT. Very tall, gorgeous grey hair and a terrific smile. He's very good looking in person, with a charismatic personality... he drives like a ****ing maniac! - YooperBrew