I got some cheap yogurt at the store today, and for some reason became curious what the “natural and artificial flavors” heading on the container meant. I ended up running across this pdf that gives definitions. Apparently natural flavor is:

The essential oil, oleoresin, essence or extractive, protein hydrolysate, distillate, or any product of roasting, heating or enzymolysis, which contains the flavoring constituents

While artificial is:

Any substance, the function of which is to impart flavor, which is not derived from a spice, fruit or fruit juice, vegetable or vegetable juice, edible yeast, herb, bark, bud, root, leaf or similar plant material, meat, fish, poultry, eggs, dairy products, or fermentation products thereof.

So, as you would expect, artificial flavoring is just that: fake. What prompted this little diversion was artificial vanilla. GourmentSleuth gives a good summary of different types of vanilla and this paper in the Journal of Chemical Education seems to be the one the wiki folks like to cite. Apparently about 1/10 of vanilla sold is actually real vanilla. Vanilla comes from an orchid and takes a ton of work. The fake stuff used to come from a by product of the paper industry. Pretty gross, but at least it came from something organic (wood). The new source: “petrochemical raw materials”