Artificial flavorreplacement.

Where the legal line sits

Under 21 CFR 101.22, natural flavor is defined by its source and function: flavoring constituents derived from listed plant or animal materials, or from fermentation products of them, used for flavor rather than nutrition. Roasting, heating and enzymolysis products are included. Artificial flavor is any flavoring substance not derived from those sources.

So natural flavor does not mean extracted from the named food, and a molecule is not artificial because of its structure. The test is where it came from.

What the label has to say

Flavors can be declared as natural flavor or artificial flavor in the ingredient list. When a product names a characterizing flavor, such as strawberry, a simulating artificial flavor means the name must carry “artificial” or “artificially flavored” at the required letter height.

That front-of-pack change is often the commercial reason for the project, so we scope it at the start.

What FDA removed

In October 2018, FDA removed six synthetic flavoring substances from 21 CFR 172.515(b): benzophenone, ethyl acrylate, eugenyl methyl ether, myrcene, pulegone and pyridine. The basis was the Delaney Clause, and FDA noted its exposure assessment found them unlikely to pose a public health risk at intended use levels. Natural counterparts of these substances were not affected.

Why a good bench sample fades in production

Most flavor compounds are small, volatile molecules. Heat can degrade the unstable ones, and spray drying is a known example. Proteins, carbohydrates and lipids in the matrix change how flavor diffuses and releases, and the carrier decides how well it is protected.

That means flavor has to be tested in the finished product, after the real process, at the end of shelf life.