GNR Mushrooms (or mold)

At the GNR party this year, some of you saw me carry out my spoils, so I thought I'd create a thread on it. Basically, brewer Maurizio Fiori told us on the tour that they throw spent grain away since there are no livestock operations in Chicago. I decided to try an experiment in growing oyster mushrooms on the mold. I've grown a few crops of oyster mushrooms in my apartment on sawdust, but they'll grow on many many things. I had some extra grain spawn, which is a mixture of various grains and flours and stuff inoculated with spores, that I had made at Kevin Hovey's class about a month ago (he has a new one coming up soon). I decided on Pleurotus pulmonarius since the two jars of culture I had looked so great (tons of nice white mycelium, when I opened the jars was greeted with nice clean "mushroomy" smell rather than the dreaded mold smell). I am just going to fruit one jar (it will give a very small crop since it's a small jar) and used the other jar to inoculate the bag of spent grain. The thing about growing these things, is that you are effectively trying to give your desired species a leg up, because honestly a lot of things want to grow on spent grain, like bad molds and bacteria. So you can either sterilize the substrate with a pressure cooker, something I haven't tried yet, or pasteurize, which can be done with a crock pot, though many models get too hot. With pasteurization the goal is to kill only some bad things so some beneficial microorganisms are left. I think mine might have gotten too hot, but we'll see. I use special heat-proof mushroom growing bags with a filter patch that allows some air in during growth.

Then you clean up real good with rubbing alcohol, sterilize any equipment with hydrogen peroxide, and mix in the grain spawn. And hope it likes its new home. So far I'm seeing some good mycelium growth and nothing obviously bad. If it goes well I can bring some mushrooms to Maurizio and maybe even get more of that brewery's waste into the hands of people who want to grow mushrooms. So yeah, cheer on the fungus and if you want to know how to grow mushrooms, let me know. All my crops have been delicious and you can't find most of these species at stores.

Here is a gross picture of what the bag looks like today in my cupboard:

I've been meaning to try a mushroom kit for years. I'm looking forward to seeing this in action.

Looking really good so far, no sign of anything bad yet, though looks like I did a bad job getting the spawn into the bottom of the bag. Hopefully the mycelium will spread there soon


I did a test fruiting with the remaining spawn and it fruited this week. Looks like I'll be enjoying one mushroom in my dinner sometime



Some of you have messaged me inquiring about getting some of you set up to grow and I'd be happy to after I see if this works.

SO cool. Can't wait to see what happens next. thanks!!

I had a problem which Kevin warned me about, which was water-logging. The spent grain was too watery and I should have mixed in straw or sawdust to dilute it. The bottom of the bag was too watery to colonize, so I cut open the bag and just saved the top part because it seemed really healthy- a good sold mass of mycellium. Normally I would have liked to grow in the bag, since it keeps moisture in, but that wasn't an option here.

I was mystified because the block smelled like circus peanuts and I really hate that candy. I almost threw it away, but it didn't smell "rotten" so I gave it a chance and it started pinning, which is the formation of baby mushrooms, yesterday.

They seem to be doing well!