Wine cask sediment is composed of two components: LEES and DREGS. LEES are the solid particles that settle at the bottom of a wine cask, while DREGS are the heavier particles that form a thick layer on top of the LEES. Both LEES and DREGS are made up of dead yeast cells, proteins, and other organic compounds that are produced during the fermentation process. The presence of LEES and DREGS in a wine cask can affect the flavor and aroma of the wine, as well as its color and texture.