Using molds in beer.

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peck

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Usually we avoid mold in beer like the plague but many of the wild brews have to have some molds that fall into the wort when inoculated. Does anyone know what, if any, effects this has on the beer? I'm guessing that the mold is out competed by the yeast and such but I'm curious about them.

I know many molds are toxic but not all of them are and as we know some are used in cheeses. I wonder about deliberately infecting a beer with a 'good' mold. I kind of doubt that the molds used in cheese making would work but still... Does anyone have any insight on this?

Edit: Well it appears that mold is used in the fermentation of sake to convert starches to sugars. Also used in the production of soy sauce. Interesting...
 
Wow.... your question needs a really long answer.

Basically, sour beers (typical brewed in Belgium now) are fermented at least partially with micro-organisms (Brett. Aceto. etc.) that eat sugars and produce acids, vinegars, and other sour compounds that give sour beers their flavor profile.

My best advice to you is to NOT infect any of your food products until you have at least a little idea of what to expect. A great place to start would be to read "Wild Brews". It is a book all about the wild and funky fermentations that create sour beers.

You do not want mold on your beer.
 
Wow.... your question needs a really long answer.

Basically, sour beers (typical brewed in Belgium now) are fermented at least partially with micro-organisms (Brett. Aceto. etc.) that eat sugars and produce acids, vinegars, and other sour compounds that give sour beers their flavor profile.

My best advice to you is to NOT infect any of your food products until you have at least a little idea of what to expect. A great place to start would be to read "Wild Brews". It is a book all about the wild and funky fermentations that create sour beers.

You do not want mold on your beer.
Yes, I've read Wild Brews. I'm specifically wondering now about the effect of molds on beer. I think I'm going try using koji (Aspergillus oryzae) which is used in the fermentation of sake in a batch. A brett. lambicus and koji batch coming up. Must ponder...
 
OK, you are actually asking about mold specifically. I apologize, a lot of people see a pellicle for the first time and think it is mold.

I do not have any experience brewing with mold. I thought koji and rice had some strange relationship where it worked but would not on other cereal grains??? I don't know. I do know that some people on here have at least attempted to brew some sake and may have more insight.
 
I think Koji can grow on any grain. I buy Miso from a farmstead producer in New England, and they make a Three-Year aged Barley Miso, which has Barley, Soy, sea salt, and Koji culture. So presumably, the koji is growing on the barley.

I believe rice is just the traditional medium for culturing Koji, but it need not be the only.
 
OK, you are actually asking about mold specifically. I apologize, a lot of people see a pellicle for the first time and think it is mold.

I do not have any experience brewing with mold. I thought koji and rice had some strange relationship where it worked but would not on other cereal grains??? I don't know. I do know that some people on here have at least attempted to brew some sake and may have more insight.
No need to apologize.

I would be interested in hearing from any sake brewers. Right now I'm thinking of throwing some steamed rice into a batch and infecting it with koji. I was considering using malt but even barring the rice-koji relationship I'm not sure what having a pound or so of malt in contact with fermenting beer would do. I'm guessing that the koji would need some sort of substrate to grow on. I wonder if oak would work, especially if I have a starchy, poorly converted wort...
 
I think Koji can grow on any grain. I buy Miso from a farmstead producer in New England, and they make a Three-Year aged Barley Miso, which has Barley, Soy, sea salt, and Koji culture. So presumably, the koji is growing on the barley.

I believe rice is just the traditional medium for culturing Koji, but it need not be the only.
I've been doing a little more reading and I believe you are correct. What to do, what to do. Oh well, I won't have time to do it until next weekend anyway.
 
My question would be...How do you know for sure EXACTLY what mold spores you would be introducing? Could be dangerous.

Too, just using wild yeasts and other organisms will NOT make Belgian beers just because you are using belgian styles and steps...that would be like me trying to make San Francisco sourdough bread here in Atlanta. You can't. Even if I started with a SF starter, it would evolve. The whole point of many of the Belgian styles is that they use yeasts that are indiginous to the area. I even wonder about this with people replicating yeasts in general. Unless one has a chem lab, microscope, and equipment...what are they really creating?
 
My question would be...How do you know for sure EXACTLY what mold spores you would be introducing? Could be dangerous.

Too, just using wild yeasts and other organisms will NOT make Belgian beers just because you are using belgian styles and steps...that would be like me trying to make San Francisco sourdough bread here in Atlanta. You can't. Even if I started with a SF starter, it would evolve. The whole point of many of the Belgian styles is that they use yeasts that are indiginous to the area. I even wonder about this with people replicating yeasts in general. Unless one has a chem lab, microscope, and equipment...what are they really creating?
Well to answer your first question, I would purchase the mold strain, through either the koji sources, cheese makers or any of the other sources out there. At least at first.

To answer your second question - I could care less about replicating any particular style. Why would I want to waste my time and effort making a beer I could just buy in the store? I do not understand peoples obsession with replicating commercial beers. There is a whole unexplored universe out there with respect to the variety of microorganism to use and the flavors they produce. Also, I LIKE the idea of using the yeasts and various beasties that are indigenous to the area I am living in and exploring the flavors they produce.

So, in a nutshell, I do not care if I am using a yeast, bacteria, mold, fungus, protozoa, amoeba, archaea or alien spores from the 13th dimension that have never been used before in any of the 'traditional' styles. Who cares what I am really creating as long as it is tasty and gets the job done.
 
peck...
others do care
one wrong micro-organism, "yeast, bacteria, mold, fungus, protozoa, amoeba, archaea or alien spores from the 13th dimension" can spoil a batch of brew...and totally ruin a day in a host of other ways.
relax...you will live longer
 
peck...
others do care
one wrong micro-organism, "yeast, bacteria, mold, fungus, protozoa, amoeba, archaea or alien spores from the 13th dimension" can spoil a batch of brew...and totally ruin a day in a host of other ways.
relax...you will live longer
If it the beer gets ruined, then I throw it out. I've done it before, sucks but if we never fail what have we learned?

Relax? Asdf...NEVER!

Different approach to beer making. I enjoy the making of new things and experiences more than purely the craft aspect.
 
I just realize something about mold:

Most molds are aerobic, they require oxygen. Koji mold used in making Sake, Miso, etc... is part of the Aspergillus genus of molds, which are highly aerobic.

Beer, on the other hand (once fermentation has begun), is a largely anaerobic environment.

If you wanted to use Koji in your beer, I'd suggest using it in your mash. I have read that it is most active around 140 degrees F, but will die off much higher than that.

Keep in mind, mold is a subset of the fungus kingdom. The yeasts which we use to ferment and mature our beer (including both Sach. and Brett.) are of the fungi kingdom. Not all fungus is aerobic, but it seems that molds are generally aerobic, which is probably one of the reasons they are never traditionally use to ferment beers.
 
And...many anaerobic molds & other organisms will kill

???

Perhaps you are thinking of botulism, which cannot live in beer because the pH is too low for it.

From what I have read, nothing that can sicken you (save alcohol) can survive in beer.
 
There isn't any known pathogen that can survive in beer. So there's no botulism concern or anything else, for that matter. The worst that'll happen trying to use mold to ferment with is it ruins the batch.

The reason people like to replicate commercial brews is because they know what they like, and want to make that. Why spend hours and hours making a batch, spending $30 to $60 on ingredients only to throw it out because it tastes like ass? Brewers by nature are a skinthrifty bunch (just LOOK at the DIY forum!) and we hate wasting money when we don't need to. I admire your spirit, peck, and keep up the good work! Hell, I have a few batches that are 'ruined' and sour but I'm keeping them around because they keep getting better with age. Soon they'll be drinkable!
 
I just realize something about mold:

Most molds are aerobic, they require oxygen. Koji mold used in making Sake, Miso, etc... is part of the Aspergillus genus of molds, which are highly aerobic.

Beer, on the other hand (once fermentation has begun), is a largely anaerobic environment.

If you wanted to use Koji in your beer, I'd suggest using it in your mash. I have read that it is most active around 140 degrees F, but will die off much higher than that.

Keep in mind, mold is a subset of the fungus kingdom. The yeasts which we use to ferment and mature our beer (including both Sach. and Brett.) are of the fungi kingdom. Not all fungus is aerobic, but it seems that molds are generally aerobic, which is probably one of the reasons they are never traditionally use to ferment beers.
Thanks for the info. I thought using the koji in the mash but I'm not going to for several reasons. First, I would lose any of the volatile flavors from the koji in the boil. Second, I would have to have a fairly good infection going to get a good effect from the koji. It might be interesting though to infect your mash at room temperature or close to it and let it sit around for a couple of days (3,5,7?) and then precede with the normal mashing process. Probably get very good conversion from it but, again, would lose any of the volatiles in the boil.

So this is my plan right now - first, I will make a starter for the koji by cooking up a couple cups of white rice and letting ferment for a couple days. Then I will cook up 2-4 pounds of either rice, wheat or oats. Right now I am leaning towards wheat but I am little concerned about all the extra crap it might leave behind. Not too concerned though. Next, I am going put the cooked grain into a bucket with the koji starter and some brett. and let the whole thing ferment for a while with a dry airlock on so that oxygen can still get in. After it ferments for three to seven days (I'll play this by ear or find some more Sake info) I'll make up a normal batch of beer, probably a mildish brown, and pitch it over the infected grain cake and ferment. Ta da!

One thing I am interested/concerned about with this whole process is the effect of having the live koji will have on the body of the beer. Since I will not be heating the koji cake, any of enzymes which the koji uses to break down the starches will still be present during the primary fermentation, which might break down the dextrins and such in the wort, leaving me with a very thin beer. Anyway, we shall see and to counteract this somewhat I'll mash the beer fairly hot (~158).

I will probably start this whole process the beginning of next week but I am going back to Seattle this weekend and the heather is blooming. I love me some heather beer!
Fresh heather >>>> dried heather, BTW.

And...many anaerobic molds & other organisms will kill
Yowser, I am going to be using commercially purchased koji which has been used for centuries to make Sake, soy sauce, miso, etc. I am not going to be scraping the black mold out of my shower and infecting my beer with it. Well, not yet, at least. Well not the black mold, there is this pink stuff...
 
Found this in The Brewers Handbook
"Beer is a poor and rather hostile environment for most microorganisms. Its ethanol concentration and low pH is lower than most bacteria can tolerate for growth. Furthermore, the high carbon dioxide concentration and extremely low oxygen content makes beer a near to anaerobic medium. Beer also contains bitter hop compounds, which are toxic. Only a few bacteria are able to grow under such inhospitable conditions and are able to spoil beer. These bacteria include both Gram-positive and Gram-negative species as listed in Table 19.2.

Gram Positive Bacteria
Gram-positive bacteria are generally regarded as the most threatening contaminants in the brewery because of their rapid growth rate and tolerance to high temperatures and low pH conditions. Most hazardous microorganisms are those belonging to the genera Lactobacillus and Pediococcus and are often referred to as lactic acid bacteria because of their propensity to produce lactic acid from simple sugars.

Gram Negative Bacteria
Important Gram-negative contaminants in the context of beer brewing are acetic acid bacteria, Zymomonas spp., Pectinatus spp., and various Enterobacteriaceae. Several members of this group not only distort the fermentation process or produce undesired by-products but also have been reported to survive the fermentation process and to transfer into the finished product.
 
peck...
others do care
one wrong micro-organism, "yeast, bacteria, mold, fungus, protozoa, amoeba, archaea or alien spores from the 13th dimension" can spoil a batch of brew...and totally ruin a day in a host of other ways.
relax...you will live longer

oh come on. Cut it out with the fear-mongering. I've made countless weird fermented products that had god knows what in them. It's next to impossible to get sick off of a wild fermentation. The biggest risk you're taking is that you might not like the flavors you get. Read "wild fermentation" by Sandor Katz.
 
not to hijack, but I am gonna try my hand at cheese making, and wouldnt be opposed to some of those cheese making critters floating into a wild beer
 
Lambic w/ cheese mold added (along with the other typical bugs) in secondary could be good - I've tasted lambics before with cheesy flavors.

Edit: Anyone willing to try putting this in their beer? - Penicillium Candidum (White)1 pack #C8
I was thinking about this as well but I was unsure if the mold would take in the wort. Maybe on barley like I'm going to do with the koji?

Speaking of koji, I have a tub of koji rice sitting in my fridge right now. I been having trouble making it to the LHBS before it closes though, so I haven't started yet. Hopefully tonight, if not tomorrow.

Boxcar - I'm a big fan of cheese as well and have thought about making my own in the past. Need to build a 'cave' to age it in though.
 
FYI-

Penicilium Candidum is an aerobic mold. It requires the presence of oxygen, and I don't think it will like the alcoholic enviroment of beer. You may be be able to convince it to grow on moistened malt though I don't think you will get cheesey flavors from it.
 
I was thinking about this as well but I was unsure if the mold would take in the wort. Maybe on barley like I'm going to do with the koji?

Speaking of koji, I have a tub of koji rice sitting in my fridge right now. I been having trouble making it to the LHBS before it closes though, so I haven't started yet. Hopefully tonight, if not tomorrow.

Boxcar - I'm a big fan of cheese as well and have thought about making my own in the past. Need to build a 'cave' to age it in though.

thermostat and free fridge from cgaigslist
 
Well I fermented my first AG batch in a paint bucket, identical to the ones they sell at homebrew shops except the lid fits a lot more losely, so air and mold got in. I still bottled and drank it, it tasted fine, really sour and moldy (like brie rind), but not in a bad way, and not oxidized! My guess is the layer of mold that formed on top stopped oxygen from reacting with the beer.

Maybe you could ferment a batch normally (something that would take well to souring) then add souring bugs and cheese mold with some sort of seal that would allow air thru but was still tight? That's what happened with me, and the results were sure interesting!
 
Well I fermented my first AG batch in a paint bucket, identical to the ones they sell at homebrew shops except the lid fits a lot more losely, so air and mold got in. I still bottled and drank it, it tasted fine, really sour and moldy (like brie rind), but not in a bad way, and not oxidized! My guess is the layer of mold that formed on top stopped oxygen from reacting with the beer.

Maybe you could ferment a batch normally (something that would take well to souring) then add souring bugs and cheese mold with some sort of seal that would allow air thru but was still tight? That's what happened with me, and the results were sure interesting!
What I was going to do with the koji experiment was use a dry airlock so that dust and crap couldn't fall into te beer but air could still get in.

I think I'm going to order some of the cheese molds...
 
Ah, what the hell... you might as well try using some penicillium roquforti (blue mold for blue cheese) and B. Linens (red bacteria on stinky cheese) in beer while you are at.

I have never heard of anyone trying cheese ripening cultures in beer, though I have heard of people using dairy lactic cultures to sour beer, and certainly many washed-rind cheeses that are washed in beer. (I sell artisan cheese for a living, btw...)

I guess there is a first for everything!
 
So I infected four pounds of wheat malt with koji rice a couple days ago. Cooked the wheat, cooled to ~130 F and mixed in the koji rice in a bucket. The mold appears to be spreading but it smells funky. Not a particularly good funky either. I attempted to keep everything sterile but I'm afraid I may have gotten a bacterial infection of some ilk.

Oh well, I'll just let it set and keep an eye on it.
 
Problem is beer is a hostile environment for mold. It is however a perfect environment for yeast and a decent environment for several bacteria. This is why beer and other alcoholic beverages are fermented with primarily yeast with some flavors coming from bacterias but not mold.

The mold is used to make sake much like a mash is used to make beer. It breaks down the starches into fermentable sugars. The mold process is aerobic and primarily solid. The result is put in a liquid and anaerobic environment for the yeast to ferment and produce alcohol.

An interesting experiment may be to try to infect barley with the koji mold, then make a beer/sake using the barley but with sake techniques. That way you would get some of the koji flavors in the beverage without usual beer boil.

Still there is plenty to play around with using wild bugs and local organisms to make a sour beer before I will start experimenting with barley sake.

Craig
 
An interesting experiment may be to try to infect barley with the koji mold, then make a beer/sake using the barley but with sake techniques. That way you would get some of the koji flavors in the beverage without usual beer boil.

Still there is plenty to play around with using wild bugs and local organisms to make a sour beer before I will start experimenting with barley sake.

Craig
This is what I did, except I used wheat malt instead of barley. I won't be following the normal sake making routine however. After it ferments for a while I will pour normal wort over the moldy wheat and then ferment normally with yeast. Assuming, of course, that it doesn't turn into the rancid funk of doom...

All this started out wondering what role, if any, mold play in the flavor of wild beers. The koji seemed to be a natural and interesting extension of this. After this experiment I will probably try some of the cheese molds as well.
 
I suppose that technically speaking, when brett forms a pellicile, it is behaving as a mold instead of a yeast.
 
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