Can a compost heap be considered a food source?

Yes, a compost heap can be considered a food source -- but not for humankind or wildlife -- even though not all edibles can go into the pile.

Specifically, the carbon-, nitrogen- and oxygen-rich materials which constitute a compost heap accept only limited amounts of human-friendly edibles. For example, it cannot have dairy and meat products or greasy, oily foods. The above-mentioned, approved materials will become food sources for microorganisms whose predatory behavior contributes to anaerobic decomposition.

Nothing in the compost pile should be attractive to human and wildlife palates.