How EvilMushroom666 Prepares Grain Spawn (Jars & Bags)
When it comes to mushroom growing everyone seems to have their own methods
and ways of going about things that works for them. Here I will document
my process of preparing grain spawn for jars and bags.
Step 1 - Soaking Grain 1. First figure out how much grain spawn you will need. For this run I
am using 15lbs of dry rye.
2. Place your grain into a pot large enough to soak and simmer. I usually
use my 21L PC or a smaller stock pot. Pour in water from the tap, as hot
as you can get it until you have a 4-5 inch water line above the level of
grain. Agitate the grain to rinse off dirt, debris and other foreign
particles. Then pour out the water and any floaters. Do this as many
times as needed until your water begins to pour clear.
First, Second and Third Rinse
3.Next add gypsum to the soak water in relation to the amount of grain
you are processing. I use a few heaping tablespoons for the batch of
15lbs of rye pictured here.
4. I now let my grains soak for 12-18 hours. After this time I place the
pot onto a burner to bring to a simmer. If I am using my smaller stock
pot I use my ceramic stove top for this part, but since I am using my
PC for the soak and simmer I am forced to use a portable stove top. I
bring my grain mixture to a simmer and then stir it occasionally for
around 10 minutes.
5. Once my mixture has simmered for 10 minutes I use a plastic strainer
to strain off excess water from my grain. MAKE sure that your grain is
properly hydrated before straining. You should be able to easily break
apart the grain using your finger nail.
Step 2 - Drying Your GrainsI have two methods of drying my grains depending upon the size of the
batch I am doing. If I am doing under 10 lbs I use two large cookie sheets
to dry out my grain. If I am doing over 10lbs I spread out a towel on
my kitchen table to absorb heat, followed by a plastic trash bag to
spread my grain on to dry.
A third option is to construct a wooden frame and staple some heavy duty
pet screen over top of it. I have plans to build myself something along
these lines in the future as my need for grain spawn is always expanding.
Method #1 - For 10lbs of grain and under1. Prepare your cookie sheets my laying down 2 layers of kitchen towel.
This will absorb any excess moisture that was left from straining. To
anyone who says this is a waste, the paper towel goes into my compost
bin after.
2. Lay down your still steaming grain onto the cookie sheet and kitchen
towel and spread evenly. I never place more then around an inch and a
half of grain onto each cookie sheet.
3. Let sit for 4-5 minutes and then move the grain around to expose any
moist grains. Keep moving the grain around every 5 minutes or so until
it is nice and dry. You can test your grain by scooping a tablespoon
onto a piece of toilet paper and leaving for 30 seconds. After 30 seconds
lift the paper dumping the grains. If any moisture spots are left on the
toilet paper the grains are not yet dry.
4. Load your grain into jars or bags as needed.
Method #2 - For more then 10lbs of grain1. Lay down as many towels as needed over your work area to protect it
from heat. Next cut as many black heavy duty trash bags as needed to
cover your work area.
2. Lay out your still steaming grain onto the trash bag and spread it
around as thin as possible.
3. Let sit for 4-5 minutes and then move the grain around to expose any
moist grains. Keep moving the grain around every 5 minutes or so until
it is nice and dry. You can test your grain by scooping a tablespoon
onto a piece of toilet paper and leaving for 30 seconds. After 30 seconds
lift the paper dumping the grains. If any moisture spots are left on the
toilet paper the grains are not yet dry.
4. Load your grain into jars or bags as needed.
Step 3 - Pressure Cooking Your Jars/BagsMethod #1 - Using JarsPreparation - Gas Exchange
Their are more then a few ways to go about making lids for your grain
jars. I personally use Synthetic Filter Discs at this point as they are
quick to prepare, reusable and all around easier to deal with IMO then
tyvek and polyfil. I simply place 2 1/4" holes in my metal lid, and then
place a SFD on top of the metal lid before screwing on the ring.
I have used polyfil in the past as well with success, I would make a hole
in the metal jar lid, ream it out to avoid cutting myself and then roll
up a ball of polyfil in my hand. I would then double it over and pull
it through the hole I had made making sure it was nice and snug.
1. After loading your jars screw down your pre-made lids.
2. Cover your jars in a layer of heavy duty tinfoil.
3. Place into your pressure cooker and follow all manufacturer's guidelines
as far as bringing it up to pressure. Be sure to allow your PC to vent
steam for 10 minutes before placing your toggle weight on.
4. Pressure cook your jars for no less then 90 minutes at 15 PSI. If
you are using larger jars then 1L add more time.
Method 2- Using Spawn Bags
.2 Micron Filter Patch Bag & Tyvek Wrist Sleeve
I am not going to lie, this is the second run I have done with spawn
bags but so far this method has treated me good, and has resulted in
clean beautiful grain bags that have gone on to fully colonized with
shiitake mycelium.
1. Put 3.5L (or more) of grain in each large gusseted spawn bag. I
use tyvek sleeves in the gusset to act as a filter for when my PC is
cooling. This prevents the contaminates that enter your PC after the
pressure equalizes from contaminating your bags.
2.Fold the gusset with the tyvek sleeve in place "accordion" style so that
it is folded back and forth over itself several times. I like to leave a little
bit of the sleeve hanging out so I can tuck the tyvek under the fold which
has the filter patch. I find if you do not do this sometimes the filter
patch can rip off while unfolding the bags. The layer of tyvek between the
filter patch and the plastic seems to help stop this.
3. Place a tinfoil buffer around the side walls of your PC and on top
of your trivet above the water line as shown below. This will stop your
bags from touching the side walls of your PC which from my experience
with sawdust substrate bags can pop holes or otherwise weaken the plastic
of spawn bags.
4. I then set a layer of jar rings on top of the tinfoil and gently
placed my grain bag into the cooker. Different PC's will allow for different
arrangements, but I can fit two bags stacked one on top of each other
comfortably in my PC, or 3 with 2 on the bottom snugged into place and
one on top. I separate my bags with more jar rings.
5. Place a plate on top of your bags to stop them from inflating during
the cycle and blocking your pressure vents. I use a plate, some people
use a plate with a 5lb weight, use whatever you have available, BUT BE
SURE TO USE SOMETHING TO STOP AN INFLATED BAG FROM BLOCKING PRESSURE
VENTS.
6. Pressure cook your bags for around 2 hours if you have used 3L of
grain or less per bag. Anymore then 3L and you should be running for
at least 2 1/2-3 hours IMO. The larger the bags the longer the PC time
that is needed to penetrate into the core of your grain. Also be sure
to allow your PC to vent steam for 5-10 minutes before placing on your
toggle weight.
7. After your run let your PC cool naturally for 8-12 hours before doing
anything. After it is cooled remove your bags gently from your cooker.
As you can see the bags seem to have a lot of condensation and moisture
on the inside, this will be taken care of during the next step.
8. Place your spawn bags in front of your laminar flow hood and assemble
your materials. You will need your regular gear (gloves, wrist sleeves,
face mask, hair cover etc) along with your tools for sanitation and to
keep with aseptic technique (ISO alc, kitchen towel etc). As well you
will need a pair of scissors and some zip ties. Wipe down your work area,
your bags, along with the scissors and zip ties.
9. Using proper sterile procedure and technique open your bags and remove
the tyvek sleeve. Be sure to always have your bags in front of the laminar
flow, especially when you pull the gussets apart. Next take your zip
tie and wrap it around your bag above the filter without coming between
the flow of sterile air and your bag opening. Quickly and carefully zip
tie the bag shut.
10. Gently shake and move around the grains to distribute excess moisture
and you will notice the wet look will go away. Set aside until you
are ready to use the bags for grain 2 grain or other procedures.
Here is a bag 4 days(First two pictures) and 8 days after inoculating with 1L of
shiitake spawn: