We bring along several different types of food when we fly in space. Since we don't have a freezer, refrigerator, stove or microwave, most of the food has already been cooked, then freeze dried and vacuum packed (meaning the water and air has been taken out of it), or it is thermally stabilized (meaning treated and sealed in a package to prevent spoiling), much like camping food. We do not want food that makes crumbs in space since crumbs would float all over the place and that could clog up equipment.