Using Spent Grains in Blue Oyster Mushroom Blocks

In the brewing process a mash is made from hydrating barley and other grains in hot water to activate malt enzymes and convert grain starches into fermentable sugars. This compounds are extracted from the grain into the hot water.

Once the mash process been completed the solids are removed in a form called spent grains. Spent grains is the biggest waste produced from the brewing process.

However this should not be the end of the road for the spent grains. We believe that they have the potential to be a great additive to our Supplemented Mushroom Blocks.

So on Thursday (22/06/2017), I got a phone call from Prancing Pony Brewery telling me that they are currently removing the spent grains.

So I visited them in Mount Barker in the Adelaide Hills and grabbed some.


I took them home and incorporated them as a supplement in the sawdust blocks and inoculated them with Blue Oyster Mushroom.

The project is doing unexpectedly well and we have very fast colonisation. Just 3 days later and the mushroom block is making good progress.

It is expected that the four mushroom blocks will be ready for postage to its customers in two weeks time by the 10/7/2017. It will come in the form of a kit and will come with a humidity tent, skewers and full instructions. Blue Oyster Mushroom Spent Grain Kit

We are excited about these kits and currently there are only 4 available. Each kit will be identified with a colored smiley face and its customers will be updated regularly on its progress in our incubator. We are hoping it gives the customers enjoyment in knowing that there is something special in the works for them.

We are trialing the Oyster mushroom species first and will soon be releasing Shiitake and Pioppino mushroom versions of these kits. We are currently growing the grain for the kits and this can be a slow process.

Forestspiral is also planning on using waste coffee grinds in their mushroom kits. We are currently seeking cafes who would be interested in donating fresh coffee grinds.