The food industry uses methyl and ethyl vanillin as less-expensive substitutes for real vanilla. Ethyl vanillin is more expensive, but has a stronger note. "Cook's Illustrated" ran several taste tests pitting vanilla against vanillin in baked goods and other applications, and to the consternation of the magazine editors, tasters could not differentiate the flavor of vanillin from vanilla; however, for the case of vanilla ice cream, natural vanilla won out. A more recent and thorough test by the same group produced a more interesting variety of results; namely, high-quality artificial vanilla flavoring is best for cookies, while high-quality real vanilla is slightly better for cakes and significantly better for unheated or lightly heated foods. The liquid extracted from vanilla pods was once believed to have medical properties, helping with various stomach ailments.