I tried to cook barley in my pressure cooker and burned the bottom. Keep in mind that it absorbs the water and you have to keep it covered, so you cannot monitor how much water is left. If you really want to try it, I would suggest that you put in more water than is normally required for barley (I think it is 3 or 3.5 to 1) and pour the excess off. After my one experience, however, I do not plan to ever cook barley or rice in a pressure cooker again.
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