Proposed rules must first be published in the Federal Register which is published daily. This is followed by a comment period wher the FDA accepts input. The proposed and final rule documents are often loaded with information. This is particularly true for major actions. I have searched the Federal Register and provided you with a few. Take a look at them so you have a feel for what is published.
Recent FR food additive notices 2002 2003
The Code of Federal Regulations is published yearly. FDA regulations can be found in Title 21.
Title 21 includes FDA's regulations
Definitions related to food ingredients are found in 170 and you should read these and compare the differences between the FD&C Act and the resulting regulations.
Things added to food must fall within regulations of FDA (unless the food is USDA regulated). The category Generally Recognized as Safe (GRAS) is one of the categories. Eligibility for GRAS status is described in the regulation 21CFR 170.3. A proposal for a self-affirmation process is currently under review. A list of substances listed as GRAS for direct addition to foods (182) contains all of those substances for which a regulation exists, but other substances may be GRAS and not on this list. Affirmed GRAS substances are found in 184. This course does not focus on indirect additives so we don't list these here. From your reading of the FD&C Act, you know that some substances have a prior sanction. This is explained and a list provided. Colors are separated into certified and exempt from certification. If they are added to food and don't fall into any of the above groups, then they must be food additives.