The Future of Diacetyl

Safety concerns over the use of diacetyl (FEMA# 2370, CAS# 431-03-8) in butter flavorings for microwave popcorn products have been a major topic in the flavor industry over the last six years, but this week the controversy moved into high gear. Is diacetyl on its way out?

The first bit of news came in the September issue of the American Journal of Respiratory and Critical Care Medicine, which published a Dutch study that pointed to a possible connection between bronchiolitis obliterans (“popcorn lung”) and diacetyl. (The researchers also identified acetoin and acetaldehyde as possible culprits.) Given recent litigation in this area, the study hardly broke any new theoretical ground.

However, news quickly followed that a devout microwave popcorn consumer in Colorado had been diagnosed with popcorn lung. The original letter from the National Jewish Medical and Research Center detailed the case of a 53-year-old man who had consumed large amounts of popcorn daily for about 10 years. If substantiated, the report moves the diacetyl conversation from the factory floor to the consumer.

The fallout: Last September, David Michaels of George Washington University (Washington, DC) petitioned the US Food and Drug Administration (FDA) to cancel the GRAS status of diacetyl. The FDA is currently reviewing the safety of the material. Meanwhile, the Flavor and Extract Manufacturers Association is recommending that diacetyl levels be reduced in formulations. While many voices in the flavor industry stress that the responsible use of diacetyl is safe for both workers and consumers, microwave popcorn companies seem unwilling to wait for the scientific verdict to come in.

Last week, Weaver Popcorn Co. Inc. (Indianapolis, IN) announced that it was dropping diacetyl from its products. The company is working with Ottens Flavors on the reformulations, which will appear on store shelves in a matter of weeks.

And now, ConAgra (Omaha, NE), the largest US microwave popcorn maker, announces that it will replace diacetyl within the next year. Brands like Orville Redenbacher and Act II will now be diacetyl-free.

Given the momentum of media attention and the preemptive moves of Weaver and ConAgra, the future of diacetyl appears uncertain.

For more information, visit the Flavor and Extract Manufacturers Association’s “Respiratory Health and Safety in the Flavor Manufacturing Workplace” page at

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