Preparing grain jars
Soak the grain
The first step is to soak the grain. Most of the time, we use organic rye (we purchase from https://grainworks.com/). Rinse the grain at least a couple of times, until the water is clear. We soak the grain for ~6 hours. We know there is lots of conflicting information on soaking grain but this is the best method that works for us. We have very low contamination rates.
Drain the grain
Right after the grain is brought to a boil, we drain it right away. The point of this is for the water on the outside of the grain to evaporate. We want the water inside the grain, not on the outside. We move the grain around a bit during this phase.
Eat a snack and let the grain cool
The grain has to be cool before you put it into jars. So, this is our snack time!
Here we have homemade bread, homemade apple butter and homemade raspberry jam. It doesn’t get any better!
Put grain into jars
We use 500ml Bernardin jars (with out lids) and add ~1 cup of grain to each jar.

Put jars into pressure cooker
We pressure cook grain at 15PSI for 75 minutes. Remember to check the lids when the pressure cooking is done, sometimes they come loose a bit.
Notes
- You have to pay attention when using jars. It is easy for the grain to become over-colonized and then it’s very difficult to use with sawdust (or whatever medium you are moving to). Make sure you shake it a couple of times before using and pay attention to the colonization rate.
- We use plastic bags when we sell grain – these jars are a good size for inoculating 2 or 3 sawdust bags but not big enough to sell (and too heavy/expensive).
After soaking, cooking and drying grain, do the jars have to go into a pressure cooker asap? I’ve heard you can keep it in the fridge for a few days before actually putting them into pressure cooker but not sure how true that is.
After cooking the grain, you need to pressure cook right away. Once water is introduced, bacteria will start to grow. The sterilization process does kill bacteria but it does not remove any potential toxins that may have been released by bacteria. It’s the same logic used in food safety and why reheating food does not ensure it’s safety. Thanks for asking!