The process of creating fish emulsion begins with whole fish, or with carcass products of fish, such as bones, scales, and skin, which are left after a fish has been processed. The fish and carcass products are then ground into a slurry. After the oils and fish meal are removed from the slurry, the slurry is officially a fish emulsion. Most emulsions are then strained to remove any remaining solids, and sulfuric acid is often added to increase the acidity and prevent the growth of microbes.