What are the facts on Mycotoxins?

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PupThePup

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All grain carries molds and fungus.

Exposure to these while harvesting/drying/storing grain can cause farmers lung or organic dust toxin syndrome.

Some of these molds/fungus make it into the malt that we buy from the LHBS.

When malting my own organic barley, I find many of the "red" colored fusarium grains (which I remove). I'm not sure what the greyish/blackish colored grain kernels contain but I remove any that are totally black or that have visible mold fungus on them. (Obviously I can't remove all of them and commercial maltsters have much better malting processes that I do. They also have automated vision systems that remove these grains.)

What are the facts on these Mycotoxins? Are they cause for concern when making malt/beer? I've read that Aflatoxin is a carcinogen. (Only facts please, I'm not interested in hearing blanket statements that "nothing survives" in the alchololic environment of beer. That is not a true statement. Fusarium infected beer will cause gushers.)

References:
http://morebeer.com/brewingtechniques/bmg/gudmestad.html
http://fyi.uwex.edu/agsafety/confined-spaces/grain-storage-and-handling/human-health-concerns-from-grain-dusts-and-molds-during-harvest/
http://en.wikipedia.org/wiki/Mycotoxin
http://en.wikipedia.org/wiki/Fusarium
 
There is a great general information paper on the US National Institutes of Health web site here and another specifically about brewing here with links to the prevalence of specific mycotoxins in various foods.

Basically it is more prevalent in nations that lack the health regulations to prevent mycotoxins from being introduced into the general populace's food supply. If one is buying malt from a reputable source grown in a regulated nation like the U.S., Canada, Australia, New Zealand, the European Nations, etc., the risk of mycotoxin being present is far less.

Personally, I'm willing to take my chances.
 
Are mycotoxins cause for concern? Yes, if I was consuming them in ridiculously large amounts.

According to this link you posted:
"An individual would need to consume several hundred liters of beer in one sitting to accumulate a lethal dose of DON"

and

"In a survey of six studies on mycotoxin contamination in beers worldwide (the studies covered 327 commercial beers from the United States, Canada, and Europe), DON was typically absent from the beers analyzed, suggesting that either FHB was not present at all in the malt or that the malting industry was effective in its screening for the disease. The highest level of DON reported was ... in a German wheat beer..."

Also, the abstract of this study suggests that we are at a higher risk of liver cancer when our diet includes a high level of aflatoxins and heavy alcohol consumption. This and this studied the levels of aflatoxins in different beers from around the world.

Here's what I take from all of this. Everything in moderation! No surprise there. Also, you may want to stop drinking cheap import beers if you want to reduce your aflatoxin intake, and like zzARzz said, buy your grains from reputable sources.

Personally, I consume most things with moderation and that works for me. The thought of mycotixins and other acute toxins are no concern for me as long as I keep a balanced diet.

EDIT: Just in case it comes up. Yes, malting, kilning, roasting, mashing, boiling, and alcohol content may kill most fungi, but if they had a chance to produce the toxins beforehand, which are a different thing, they will be in the beer. No amount of boiling will get rid of all of them.
 
Over the years I've put a ton of information on that issue as well as other safety concerns that nervous noobs stumble upon and freak out about.....The bottom line, except for nervous noobs, very few of us worry about it.

We've covered everything even with some citations in this thread. Dangers of Homebrewing

And some more info here as well.

It covers all the bugaboos that new brewers wanna fear, botulism, mycotoxins, e-coli, zombies....Including just about everything that julioardz brought up....Which are pretty much all the same conclusions.

The bottom line is, you can choose to freak out about it OR you can realize that there are billions of folks drinking beer on this planet, and millions of them brewing their own, AND we're all still alive, aren't we? ;)
 
I don't know much about mycotoxins related to food in general, but know a little bit about aflatoxins. When you see black mold on the grains, it usually has high levels of aflatoxins. They're cumulative, which means that even smaller amounts can become harmful if ingested repeatedly over prolonged periods of time, and acute reactions are almost unheard of. They're especially damaging to the liver, but thankfully humans have a relatively high tolerance.

Aflatoxin producing molds love peanut shells, and peanut butter producers sometimes struggle to keep levels under the FDA threshold. All commercially grown grains that are destined for human consumption are also tested for aflatoxins, and any that test above the threshold are discarded, since they're even more toxic for animals than they are for us. Mesquite pods are also known to carry large amounts of aflatoxin producing molds, and a professor at the local university was hospitalized for acute aflatoxin poisoning after eating a large quantity of mesquite pod pudding that he had made for a study on indigenous foods.

If you're worried about aflatoxins and other mycotoxins in beer brewed from home malted grains, you can use bentonite as a fining agent, as it will remove the vast majority of any mycotoxins that might be present (as well as clear your beer). It's used a lot in winemaking, and is available at most homebrew stores. This is what I do when making beers with mesquite pods. Unless you're using mesquite pods or home malted grains or something else that could potentially have a lot of mycotoxins in it, it's not something to worry about IMO. Even then, adding the bentonite is probably overkill, but I figure the alcohol is doing enough damage to my liver, and it's easy enough to add.

This is all just my understanding of it, based on talks with a friend and fellow homebrewer who works as a toxicologist.
 
@JuanMoore - Thank you for the reasonable response. The information you provided is very helpful. I know when malting my grain I've found black/grey grains which I do remove along with the red fusarium grains. Not sure I've ever found aflatoxin as the moldy grains that I remove are usually more greyish than black. It's interesting that you mention bentonite as a fining agent, I'll have to try that. How's mesquite pod beer taste, I'll have to try it sometime, do you have a recipe? I've heard of mesquite wood smoke flavor.
 
@JuanMoore - Thank you for the reasonable response. The information you provided is very helpful. I know when malting my grain I've found black/grey grains which I do remove along with the red fusarium grains. Not sure I've ever found aflatoxin as the moldy grains that I remove are usually more greyish than black. It's interesting that you mention bentonite as a fining agent, I'll have to try that. How's mesquite pod beer taste, I'll have to try it sometime, do you have a recipe? I've heard of mesquite wood smoke flavor.

When roasted lightly the mesquite pods can be used like a specialty grain in just about any recipe. They have some cinnamon, vanilla, and light caramel flavors, and kinda smell like honey bunches of oats cereal when roasting. They're also ~30% sugar by weight, so they add a fair amount of fermentables. I've used them in a porter, IPA, APA, and an alt beer using belgian yeast. I think they'd work really well in a holiday beer, but haven't had a chance to brew one yet. There's a few threads here on HBT about brewing with mesquite.
 
Good timing on the question. I'm just preparing to start surveying PA farm fields (wheat and corn stubble) for a new isolate of Fusarium graminiarum that produces higher levels of the tricothecene family of mycotoxins.

The upshot is, I would not worry about this as far as malted barley is concerned. The malsters are all up on this and every truckload of grain is being tested. Over the limit, and the maltsters won't buy it. Then if is sold as animal feed - as long as that higher limit is not exceded. The toxins are less of a problem for cows, and even less for chickens.

The mycotoxins are fairly stable and some ethanol plants have run into problems disposing of the used distillers grain (largely corn) as their processing results in an accumulation of the mycotoxins in the spent grain so there have been some issues with using that as animal feed. We know a fair bit about the fungus on wheat as we humans eat that directly. We know much less about it in corn and other crops. We need to do more research (and $$ to do said research)
 
If you are malting your own grain, than this could be an issue. Picking out any reddish grains is advisable. I'm not sure what else they do commercially, but I have heard that they actually will innoculate the grain with lactobacillus as this bacteria has been shown to suppress the growth of other microbes. As the link you provided says, while the roasting will kill the fungus, if there is substantial fungal growth during the malting process, you can get extra mycotoxins produced which could make it into the final product
 
If you are malting your own grain, than this could be an issue.

Agreed, it is most definately an issue.

Picking out any reddish grains is advisable.

In 25lb sack of grain, I sometimes pick out as much as a 1/4 - 1/3 cup full of red grains. It varies some bags contain less some contain more.

I'm not sure what else they do commercially, but I have heard that they actually will innoculate the grain with lactobacillus as this bacteria has been shown to suppress the growth of other microbes.

Yes, I have thought of adding lactobacillus to the steeping water. Not sure if that would work though.

As the link you provided says, while the roasting will kill the fungus, if there is substantial fungal growth during the malting process, you can get extra mycotoxins produced which could make it into the final product

Precisely. I believe White Labs will do an analysis on your beer (not cheap). Might be worth spending the money on beers made with my own malt just out of curiosity.
 
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