The heat from jalapenos (and all hot peppers) comes from the membrane on the inside of the flesh. Shave that off and you'll get flavor not heat. Sample every so often just so you get the flavor you want.
I made a jalapeño beer about a month ago. I cleaned 10 peppers and added them to 5gal american ale in the secondary for 7 days before kegging. The flavor and smell is there without the heat. Friends really are liking it.