Is Diacetyl Killing Us?

[Breifne]

A study done on the air quality in a handful of Wisconsin roasteries has sounded the alarm on this. I'd like to get veteran roasters' thoughts on this ... especially any who have looked into this potential risk themselves:

Coffee roasters' health at risk from chemical compound, air samples suggest

 

[topher]

The roastery located in Deerfield that was mentioned in this article was where I roasted for 9 years. I was set up one day for failure. The new owners were coming in to see the new plant. My employee came to me saying (in a rehearsed manor) that he was experiencing carbon monoxide poisoning. He then quoted exactly what he was feeling as if being read out a book. I told him to go and get checked out by the workers comp doctor. The new owners came in and watched as I roasted on 3 machines at once. The next day the employee came in with a smirk and said sorry about yesterday. You must have looked bad since I left. I explained that I actually looked like a rock star running everything so smoothly. The doctor found nothing wrong with him. He continued to push that it was an unsafe work environment. The company paid 2 different companies a lot of money to come in and test the air. Someone also called the EPA who did testing as well. We passed with no issues. There was not one time any employee passed out at work as was mentioned in the article. I read this article a week ago....I was not happy. It's funny that the plant mentioned ran for years with no issues after one employee was let go for other non related reasons.

 

[Breifne]

Wow ... that's nuts. Thanks for that valuable background on this piece, Topher.

 

[ellatas]

It is something to watch. It would appear documented cases were associated with butter flavouring, but roasted coffee is still a source for Diacetyl nonetheless. The EPA is likely to come up with dosage limits which may mean the room's air handling systems need to be upgraded to more than 3 air changes per minute. To minimize the likelihood of high concentrations, one could direct the air discharge from the roaster cooling tray, pneumatic conveyors and dust collectors to the outside. Also, place a fan near the grinder and any ground coffee degassing bins to ensure there is good air movement.
Typically at large roasting facilities, they will measure the oxygen content in the room near grinding and degassing since the heavier degassing gases (mostly CO2) will displace oxygen and it could make it hard to breathe. Increasing the room's fresh air volume (and resulting air changes) resolves this issue. So does having a sealed grinder and vents on ground coffee bins that discharge outside.

 

[jeremy8810]

I read the article and went and got a lung capacity test the next day. Everything was normal for my age, height, and weight.

I've been roasting for over 2 years now on a 10 kilo machine. When I started I was probably in one of the worst ventilated situations for that size of a machine. I was in a 140 sq. ft. room with no windows, and I had to leave the door shut because it led outside. I also didn't have any vents or fans. I only had a little tiny window AC unit. Over time, I've added a screen to the door, so I can open it. I've added a fan, gotten a better window unit, and now I'm installing a vent by the cooling bin.

I don't really grind a whole lot for wholesale customers, so I can't testify to that. I know the article said it was 3-5 times worse by the grinding equipment.

I'm not a scientist by any stretch of the imagination, but I think as long as we are doing our best to keep it well ventilated, we should be ok. I'm going to start wearing an N91 respirator (like the ones painters are supposed to wear), until more information comes out. The article definitely scared the crap out of me, but I think I'm coming down from my hysterical high, and am feeling ok now.

 

[topher]

I have had my lungs checked due the fact that I smoked for many years...I quite 14 years ago. I have been roasting from 22 years. I have no issues with my lungs. Side note the roastery I was speaking of had plenty of ventilation. Make up air and loads of fans. Like I said before we had 2 outside companies test the air quality as well as the EPA after they received an anonymous call after someone that didn't like the results from the first 2 tests.

 

[qwe7410]

I don't get it, it says that the grinder area is morediacetyl loaded.

If that's the case, won't baristas at the cafe, grinding before making every cup be at greater risk?