The foods in the data sources supplied with FoodWorks are referred to as reference foods. They are not FoodWorks documents and are not modifiable by you.
When you are entering foods or ingredients into a diet or recipe, reference foods are listed for you to select from in the drop-down list box. (Your own foods and recipes can be listed here as well).
The reference foods available to you are determined by the data sources selected for your database. See: How do I choose data sources (food selections) for a database?
You can search for and rank reference foods by nutrient in the query foods window.