sentence2_structure: The energy content of foods<>is expressed<>often
sentence1: In the nutritional literature, the energy content of foods is, by convention, expressed in Calories (note the capital &quot;C&quot;) as opposed to the use of calories or kilojoules (kj) in the scientific literature.
sentence2: The energy content of foods is often expressed in calories.
question: Energy contents of foods are often expressed in what?