or blended with sugar, starch, or other ingredients) Extract (in alcoholic or occasionally glycerol solution; both pure and imitation forms of vanilla contain at least 35% alcohol) Vanilla sugar, a packaged mix of sugar and vanilla extract Vanilla flavoring in food may be achieved by adding vanilla extract or by cooking vanilla pods in the liquid preparation. A stronger aroma may be attained if the pods are split in two, exposing more of a pod's surface area to the liquid. In this case, the pods' seeds are mixed into the preparation. Natural vanilla gives a brown or yellow color to preparations, depending on the concentration. Good-quality vanilla has a strong, aromatic flavor, but food with small amounts of low-quality vanilla or artificial vanilla-like flavorings are far more common, since true vanilla is much more expensive. Regarded as the world's most popular aroma and flavor, vanilla is a widely used aroma and flavor compound for foods, beverages and cosmetics, as indicated by its popularity as an ice cream flavor. Although vanilla is a prized flavoring agent on its own, it is also used to enhance the flavor of other substances, to which its own flavor is often complementary, such as chocolate, custard, caramel, coffee, and others. Vanilla is a common ingredient in Western sweet baked goods, such as cookies and cakes. Despite the expense, vanilla is highly valued for its flavor. 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. Contact dermatitis The sap of most species of vanilla orchid which exudes from cut stems or where beans are harvested can cause moderate to severe dermatitis if it comes in contact with bare skin. The sap of vanilla