The best known contribution of lipids to flavor is as precursors. The compounds formed may be readily volatile and have appreciable odors-e.g., lower molecular weight aliphatic aldehydes, ketones, and fatty acids. The intact lipid or low volatile breakdown products of lipids contribute to flavor largely through mouth stimulation. The taste of such compounds as well as their effects on the rheological properties of foods will be discussed. In addition, lipids may modify the flavor of other compounds, particularly those of low polarity. © 1969, American Chemical Society. All rights reserved.