Ltering the Caloric/Fat Content of Food

We studied thermochemistry having to do with caloric content of food and how that is measured. The subjects we dealt with were heat flow, the joule, exothermic and endothermic reactions, and the formula for specific heat.
I thought it would be interesting to write a paper on how caloric or fat content is altered in food using these concepts and tracing the process say with milk or cheese etc. Maybe beginning with how to find the caloric or fat content of a piece of cheese or sample of milk and then explaining the process used to alter the makeup of the sample to make it low fat, fat free etc.
This is a sophomore level high school paper so nothing too complex. The teacher wants a bibiliography with three sources, MLA format and we can include formulas, or diagrams. At least one formula would be good.
I do not have too many specifics on the topic as long as it is generally in that area.