I learned that I need to clean the rollers on my grain mill today. No idea why it stopped working today after a year and a half, but it just sat there. It wouldn’t grab the grain. So I dumped the hopper, took a wire brush to the driven roller… not enough. cleaned both of them and the mill works again. Who knew? Not me.
I use a small paint brush (designated for this purpose only) to brush the rollers after each use. I find it works fine doing that.
I take mine apart once a month. I like to tinker and it feeds my ADD. Also i believe it will help prevent any musty issues since a dirty mill can harbor bacteria.
Of course malt has plenty of bacteria on it.
Well, According to http://fantastic-flavour.com/yahoo_site_admin/assets/docs/Mustyoffflavoursinbeer.234234915.pdf Apparently musty can be located in every aspect of brewing. Id always heard most of it associated with bad grain/Mill problems.
I’m sure the flour in the mill knurls will oxidize too. Mold is often the cause of musty flavors/aromas, and some can be detected at ppb levels.
One local small place put the mill in a contained area, to cut down on airborne microorganisms. Big production breweries have a mill room.
I don’t know if some of the commercial mills I have seen are routinely cleaned.
Thanks for the link, will read.
I don’t believe the “musty” issues are a concern at the homebrew level unless one’s practices are generally unsanitary and lax in regards to critical spots in the system. And, the submitted abstract really seems to be concerned with the other primary areas of the brewery and the shipping conditions of the malt. So moldy slimy malt present in your grist certainly could be an issue. I’ve had problems with the bottom of the bag of malt being moldy due to obviously damp shipping conditions.
Keeping the rollers free of built-up debris is a great habit to develop. I’ve never really had a problem except when trying to condition the malt. My opinion is that its purported benefit is dubious. Furthermore, this is a way to introduce moisture to a specific area that really has little use for it and has lots of nooks and crannies to harbor impacted flour.
The knurls on my BC have worn slightly and the rollers need some assistance- so I slipped an o-ring over the passive roller and the problem has been eliminated. The o-ring breaks periodically and is easily replaced.
I used to crush using a Valley Mill, but have all but abandoned it. I just have it milled at the homebrew shop. I found I was spending alot of time on brew day tinkering with getting the rollers “just right”. And I only buy what i use, so I dont have all sorts if malt/specialty grains sitting around getting old and “musty”. Only drawback is once it’s crushed, it should be brewed fairly quickly to retain its freshness.
I, too, only buy what I will be using in the next week or two so I also have it milled at the shop. I once asked the man behind the counter how long my grain would be good and he said I had up to 2 months to use it. I never wait that long and I start to get nervous after two weeks.
It’s actually pretty amazing how long grain can last crushed. Keep it sealed and dry and it can last 6 months easily.