Hier übrigens das entsprechende Zitat aus „modernist cuisine“:
„One way to determine the number of calories in a food is to place a sample of it in a pressure vessel (or „bomb“), flood the chamber with pure oxygen to a pressure of 20 bar I 290 psi, then use a red-hot, electrified platinum wire to set the food on fire. As it burns, the food heats water around the bomb, and a thermometer measures the temperature increase, which is then converted into calories. Although this method is fast and convenient, it is not especially accurate because the energy obtained by busting the food is not the same as the net energy obtained by digesting it in. Some foods, such as those very high in insoluble fiber, burn well but pass through the body largely undigested.“