Food manufacturers are sometimes reluctant to inform consumers about the source and identity of flavor ingredients and whether they have been produced with the incorporation of substances such as animal byproducts. Some flavor ingredients, such as gelatin, are produced from animal products. Some, such as glycerin can be derived from either animal or vegetable sources. And some extracts, such as vanilla, may contain alcohol. Many groups such as Jews, Jains, Hindus, and Muslims, as well as vegans follow dietary restrictions which disallow the use of animal byproducts and/or alcohol in certain contexts. In many Western countries, some consumers rely on a Jewish kosher pareve certification mark to indicate that natural flavorings used in a food product are free of meat and dairy (although they can still contain fish). The Vegan Society's Sunflower symbol (which is currently used by over 260 companies worldwide) can also be used to see which products do not use any animal ingredients (including flavorings and colorings).