Diacetyl

Diacetyl, or 2,3-butanedione, is a yellow-green liquid with a quinine-like odor. It is a component of butter, natural oils, and alcoholic beverages. Food manufacturers often add diacetyl to foods to impart a buttery taste. It has been linked however, to a rare, fatal lung disease suffered by microwave popcorn plant workers; this use was discontinued in 2006. More recently, R. Vince and co-workers at the University of Minnesota found that diacetyl accelerates amyloid-β aggregation in Alzheimer’s disease patients.