About Diacetyl & Coffee Roasting
Diacetyl is a substance found in many surprising places – like human breath, cigarette smoke, and many common foods. In terms of coffee, it is produced naturally in the roasting process.
While diacetyl occurs naturally during the production of certain foods and beverages, it was also historically added to flavorings for its buttery taste. Today, added diacetyl has largely been removed from flavorings - often substituted by compounds like 2,3-pentanedione (which also share similar concerns for occupational exposure limits). However, naturally-occurring diacetyl may still be present.
Similar to many things we may eat, drink, touch, or inhale, there are typically established amounts, concentrations, or levels of exposure that are considered safe for human health. Foods and beverages containing diacetyl are not unhealthy as a result. However, concerns have been raised with respect to workers who may be exposed on a consistent and concentrated basis to diacetyl vapors.
Scientists are not unanimously sure what level of exposure is appropriate in a workplace setting. Despite varying opinions about this potential hazard, there are a number of exposure guidelines and recommended precautions that have been suggested by various authorities (described in the NCA members-exclusive FAQ below).
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Coffee Industry Resources
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Industry Feedback Appreciated!
The NCA invites members of the industry to let us know what we should address in upcoming diacetyl training and education, and other areas of interest. Your feedback will help us develop future NCA content and resources.
Specific questions and constructive comments are also welcome. Please submit those here.
Disclaimer: We invite you to review these resources to ensure that your workplace is as safe as possible – and compliant with all applicable laws and regulations. NCA’s Guide to Workplace Safety, and the resources provided within The Guide are not meant to be a substitute for on site assessment, evaluation, hazard control, and training, which is the responsibility of coffee organizations, which should consult with qualified industrial hygiene professionals to implement workplace safety programs.