34pentanedione

34pentanedione, also known as diacetyl, is a chemical compound with the formula (CH3CO)2. It is a diketone, meaning it contains two ketone functional groups. Diacetyl is a yellow liquid at room temperature and is known for its intense buttery flavor and aroma. It occurs naturally in many fermented foods and beverages, including butter, cheese, beer, and wine.

Industrially, diacetyl is produced through chemical synthesis. It is widely used as a food additive, particularly in the flavorings industry, to impart a buttery taste to products such as margarine, popcorn, caramel, and baked goods. It is also used in some e-cigarette liquids to create a buttery flavor.

While diacetyl contributes desirable flavor characteristics, its inhalation has been linked to serious respiratory problems, notably bronchiolitis obliterans, often referred to as "popcorn lung." This association has led to concerns and regulatory actions regarding occupational exposure in food manufacturing facilities and among vapers. Consequently, there has been a push for diacetyl-free flavorings and increased safety measures in industries where exposure is a risk. Research continues to explore the health effects of diacetyl and to develop safer alternatives.