What is malt dust? How does it form? Why dangerous?

[Finlandbrews]

I have read that one criteria for malt quality is the level of malt dust rejected in the malting process (how little malt dust is on the malt) but I understand from my malt sheet which says "do not inhale the malt dust" that my malt potentially has levels of malt dust that can be high enough to be cautious.

My questions are:

How is this malt dust formed?
Can this malt dust build up once malt is in the sacks/package or only during the malting process?
Why is it dangerous for health?
Is it observable under microscope?
Can this malt dust provide off flavour to the finished beer?
Can it be removed somehow, for example by wet milling?

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[bucketnative]

Probably due to Baker's Lung: https://www.ncbi.nlm.nih.gov/pubmed/9847440

It's also just good practice not to breath in particulate. Look at silicosis, asbestosis, smoke inhalation, etc... Although these are a different mechanism than the flour dust.

It's probably not a big deal on the homebrew scale, but on the industrial scale with chronis exposure it can pose a real hazard.

Also, on the industrial scale, you could have an explosion related to malt dust. Imagine millions of particles with a high surface area to volume ratio igniting at once in a large cloud. (https://en.wikipedia.org/wiki/2008_Georgia_sugar_refinery_explosion)

 

[NCSU_Brewer]

Probably due to Baker's Lung: https://www.ncbi.nlm.nih.gov/pubmed/9847440

It's also just good practice not to breath in particulate. Look at silicosis, asbestosis, smoke inhalation, etc... Although these are a different mechanism than the flour dust.

It's probably not a big deal on the homebrew scale, but on the industrial scale with chronis exposure it can pose a real hazard.

Also, on the industrial scale, you could have an explosion related to malt dust. Imagine millions of particles with a high surface area to volume ratio igniting at once in a large cloud. (https://en.wikipedia.org/wiki/2008_Georgia_sugar_refinery_explosion)

Winner winner.

 

[pigroaster]

And I thought brewers said "Malt dust" when they cursed just like farmers say "Heifer dust"!

Seriously dust is a big concern at feed mills and drying systems around me in Canada. Just keep your head back when you pour malt in your mill! Dust is bad long term to your health without breathing protection. A paint mask would help you if you are concerned. Hospital masks are also fast and cheap. Sorry to make fun of a serious commercial problem.

 

[skraeling]

Probably due to Baker's Lung: https://www.ncbi.nlm.nih.gov/pubmed/9847440

It's also just good practice not to breath in particulate. Look at silicosis, asbestosis, smoke inhalation, etc... Although these are a different mechanism than the flour dust.

It's probably not a big deal on the homebrew scale, but on the industrial scale with chronis exposure it can pose a real hazard.

Also, on the industrial scale, you could have an explosion related to malt dust. Imagine millions of particles with a high surface area to volume ratio igniting at once in a large cloud. (https://en.wikipedia.org/wiki/2008_Georgia_sugar_refinery_explosion)

beat me to it. stuff in lungs other than air = bad 100% of the time (not talking medicating nebulizers either you smart asses ).

 

[Radboud]

And I thought brewers said "Malt dust" when they cursed just like farmers say "Heifer dust"!

Seriously dust is a big concern at feed mills and drying systems around me in Canada. Just keep your head back when you pour malt in your mill! Dust is bad long term to your health without breathing protection. A paint mask would help you if you are concerned. Hospital masks are also fast and cheap. Sorry to make fun of a serious commercial problem.

Proper protection (other than overn mitts) is something that a lot of homebrewers don't seem think about. I always wear a dust mask / face protection when working with stuff that generates dust or spray (malt, pbw, star san etc). Better safe than sorry! Ever had a lungful of star san mist? It ain't very nice!

 

[kh54s10]

When you mill, or pour the grains into your mash tun. KEEP YOUR HEAD OUT OF THE DUST CLOUD. No need to get crazy about things.

 

[Barley_Bob]

I worked in a grain elevator for a while, and grain dust is quite hazardous for your health. And it is also quite explosive.

Not that I'm going to encourage anyone to risk their health, but I will say that the small amount of grain dust a homebrewer is exposed to is just peanuts compared to what a farmer or someone in ag services deals with. If you have a chronic health condition, you should for sure wear a mask. Otherwise, I wouldn't sweat it.

I wish I had a picture of me to post after cleaning a grain bin... Well, imagine taking a shower with your clothes on and then swimming in flour. That's what it looks like, and it's a whole nother level of dust.