5 replies to this topic

[Hippie3]

Pasteurized Wheat Straw Prep TEK

Introduction:

The following procedure is a simple method for pasteurizing wheat straw and is ideal for the small-scale home cultivator. The number one benefit of working with a bulk substrate like Pasteurized Wheat Straw (as far as the small-scale cultivator is concerned) is the impressive boost that it offers in terms of overall performance and cropping yields. Fruitbodies grown out on WS are typically much larger than ones that are grown out on grain or flour. Colonization (or Spawn Run) times are also decreased which means that the mycelium grows more rapidly in straw than it does in grain or flour.

Wheat straw is an ideal substrate for these particular mushrooms and for this particular application. In fact, given its cleanliness, ease of preparation, and nutritional benefits; it may be the best alternative for any indoor cultivation app where these (or other similar mushrooms) are concerned.

The type of straw that we will be using is known as Wheat Straw and is commonly used amongst commercial grow-ops for creating composts to be used with edible mushrooms that require it. For small-scale apps, straw can be used as a primary substrate for this particular kind of mushroom.

Wheat straw can be purchased at any feed store for approximately $5 for 1 bale. One Bale weighs approximately 40 lbs dried. That is a lot of substrate for the price! Other places that are likely to carry wheat straw are; gardening centers or nurseries (frequently used for landscaping). You should be able to find straw at any one of these places with little effort.

Note: Be sure not to use an Oat or Barley type straw. Make sure that you are purchasing "wheat" straw!


Overview:

Below is a list of all the items you will need to carry out this procedure:




Large pot for boiling water (5-7 Qt.)
2 lbs or more of wheat straw
A metal grate or a heavy weight (for holding the straw under water during pasteurization.)
1 Meat probe Thermometer
A pair of scissors for cutting up straw.
A large container (for holding the chopped straw)


Wheat Straw Preparation:

Place the following items in your workspace:



Bag of Wheat Straw
2 large bowls or pans


Procedure:

Before you begin, you will want to fill the large pot with water (about 1/2 - 3/4 full) with tap water like so:




Place the pot of water on the stove top and turn the stove on to begin the boiling process:



The water water should be allowed to boil for 20-30 minutes before adding straw. (This gives us plenty of time to chop the straw down to size in preparation of the pasteurization process).

Chopping the straw:

Overview:

The straw needs to be chopped down to a reasonable size so that it is easier to work with for our particular application. Generally, wheat straw should always be chopped down to 1-3 inch lengths which allows for a better substrate medium for both the cultivator and the mushrooms. The idea is to compact as much substrate mass as possible into a given area which increases your cropping efficiency while offering the mycelium a more ideal medium to colonize over. Cropping efficiency, in this case, is determined by how much substrate can be packed into a given area. This is essentially what determines the yield for a given substrate mass or "cake". In other words; a substrate/cake that is more compact or dense will produce greater yields than one that is less dense or compact.

Procedure:

Since we will be using such a small container to house our substrate/cakes, we will need to chop the straw down to the minimum possible length desirable. 1 inch is a good length for this particular application.

Start by grabbing a hand full of straw, and while working over your tray or bowl, begin cutting the loose pieces of straw off the end of the bushel like so:


Work your way down, one inch at a time, until you're able to get an even egde to work from (see pic below):


Continue to cut the bushel down to 1 inch lengths and repeat this procedure until you have at least 2.5 to 3 times the amount of mass that you plan to fill. Below is a picture of the final batch of straw ready for pasteurization:

NOTE: I FOUND A REGULAR BLENDER QUITE EFFECTIVE AT CHOPPING DRY STRAW, I USED A PLASTIC CUP AS A 'PUSH STICK' TO FEED THE STRAW TO THE BLADES
Pasteurization:

Overview:

In order for pasteurization to be completed, Wheat straw is bathed in a pot of water at 160-170'F for a total of 30-45 minutes.

The pot of water should have had plenty of time to come to a boil and remain for 20-30 minutes:


Before we can add the straw to the pot of water, we need to lower the temperature of the water to a point below boiling that is ideal for pasteurization to proceed. To do this; simply turn the stove dial down by 1/3 or 1/2. Using the Meat Thermometer Probe; periodically check the temperature of the water until it nears the ideal range for pasteurization (160-170'F):


Once the water temperature is down within range; you can begin to add the straw into the water. This is the point where you should start your 30-45 minute countdown:


After filling the pot with a portion of dry straw, force the floating straw down under the water with a heavy-duty utensil for total submersion:


Repeat this procedure of filling and sumberging the straw into the pot of water until you have added as much straw as necessary for your application (or as much as can possibly be contained in the pot your working with):


Using a grate (or some form of heavy-duty material that will alow you to hold the straw submerged under the water for the duration of the pasteurization process), force the straw down into the pot of water like so:


Here is a close up view of the type of grating that was modified to fit this pot for this particular purpose:


Now, you will need a heavy weight of some kind to place on top of the grate in order to keep the straw forced down into the pot of water. I used a couple of weights from a weight-lifting set and wrapped them in a heavy-duty plastic bag, like so:


Be sure to use the thermometer probe to gauge the temperature of the water. It's important to keep an eye on the gauge to make sure that the straw remains within the ideal range for the duration of the pasteurization process.

Draining water from straw:

Once the straw has been fully submerged and pasteurized for the 30-45 minute time period, the stove shouldbe turned off and allowed to cool down for about 10 minutes before draining the water out of the pot.

In the pic below, you can see how the leftover water from the pasteurization process was drained (and strained) into a 1 QT jar where it will be saved for another batch of grain:


Below is a picture of the final product of the drained wheat straw juice that will be used on the next batch of grain jars in place of bottled water, which will provide the spawn jar with a nutritional boost that will help to speed up the colonization cycle considerably.


Once the water has been drained from the pot, it's time to move the freshly pasteurized straw into a heavy-duty plastic bag where it can be allowed to cool down to room temperature before being spawned.

I recommend tying the bag up and poking about 20-30 holes into it with a clean nail or similar poking device and allowing it to hang for a 4-6 hour time period until it has had plenty of time to cool back down to room temperature. (see pic below)


Below is a picture of the final product after pasteurization and draining is completed:


Once the straw has cooled down to room temperature, you can proceed to the following TEK where you will find the necessary information for spawning the freshly pasteurized wheat straw with a pre-colonized jar of grain spawn:

Wheat Straw Spawning TEK

[Hippie3]

Spawning Pasteurized Wheat Straw:

Overview:

Below is a list of all the items you will need to carry out this procedure:



Pasteurized Wheat Straw (cooled to room temp)
1 QT Jar of Grain Spawn (or colonized BRF)


Initial Preparation:

Before we begin, it's always a good idea to wash your hands and clean the work space that you will be working in before you get started. I recommend saturating a paper towel with rubbing alcohol and wiping your hands down thoroughly with it, paying close attention to your finger tips and nails where dirt can be easily trapped.

Spawn Preparation


The jar of grain spawn that you will be using to spawn the PWS with will need to be shaken first before applying to the prepared substrate. However, it is important that the grain is allowed to recover from the shaking for a 24 hour period before spawning takes place. The best time to shake the spawn jar is the day before pasteurization takes place. After 24 hours, the mycelium has had a chance to re-colonize and should be checked very closely for contamination before being used as spawn.

By doing this, you are allowing the mycelium to recover from the transitional state into an active state that will ensure rapid colonization of the wheat straw... which is very important. The mycelium needs to colonize the pasteurized wheat straw as rapidly as possible in order to beat the contaminations from taking over the substrate first. Once the mycelium has extablished itself in the substrate, it can easily fight off the contaminations that may be present. However, in it's transitional state, the mycelium is very vulnerable and has no way to protect itself from the competing contams that are present in the bulk substrate.

In the picture below, you can see the jar of colonized grain spawn ready to be shaken so it can be used to spawn our soon-to-be pasteurized wheat straw:


Below you can see how the colonized grain has bonded together so that when it is shaken considerably, it still remains in tact. It's important not to let a grain jar colonize much further beyond this point or you will likely never break it apart!


But, this spawn jar is right on schedule and as you can tell by the pic below, it gave in after a few good shakes.


The picture above was taken directly after the spawn jar was shaken and is not ready to be transfered to the Wheat straw yet. It needs to be placed back into incubation for another 24 hour period so it can recover a little before it can be used as spawn for the wheat straw. Below is a picture of the spawn jar 24 hours after shaking and directly before being used as spawn for the wheat straw:


As you can tell by the picture above, the jar of grain has had a chance to recover from the shaking that took place the day before and appears to be ready for spawning.


Spawning Procedure:

First, you will want to shake the bag of pasteurized straw and then open it up as wide as possible, like so:


Next, very lightly shake the recovering spawn jar just enough to break the kernels apart (being careful not to disturb the recovering mycelium anymore than necessary). Now open the jar up and pour about 1/5th of the grain spawn out over the surface of the straw, like so:


With clean hands (as described above); work the grain into the straw by turning it over so that the grain mixes well with the straw, like so:


Repeat the process of adding grain to the straw and mixing the two together until the entire jar of grain spawn has been added to the substrate, like so:


Once all the grain spawn has been added to the bag of straw, the bag should be tied and shaken thoroughly to ensure proper distribution of the grain kernels throughout the bag of straw.

[Hippie3]

Grain Prep TEK

Introduction:

The first item of consideration when working with grain is a pressure cooker for sterilization. As far as I know (aside from an autoclave), a pressure cooker is the only way to get the grain hot enough in order for it to become properly sterilized.

For this TEK, we will be using a pressure cooker which holds 7 - 1 Qt. sized canning jars. (see pic below)



The type of grain that we will be using is known as rye grain and is the most commonly used type amongst commercial grow-ops for creating spawn used with bulk substrates and edible mushrooms. For small-scale apps, grain can be used as a primary substrate or can be used to spawn more prepared grain (which allows one to extend a live culture or spawn to create more substrate mass to fruit from). And, as with the commercial application of grain, it can also be used to spawn bulk substrates like compost or pasteurized wheat straw, etc… to achieve greater yield potential.

Below is a photo reference of the rye grain that may help you to locate what you need. It is also referred to as rye berries. It is actually both of these, so don’t be discouraged if you hear it referred to as something among those lines. You should be able to purchase these rye berries at any local health food store or food co-op that handles bulk foods. You will find it in the bulk food section and should be able to buy it by the lb. It usually goes for 80-90 cents/lb, so it’s worth it to buy a few pounds at a time for future use.



Overview:

Below is a list of all the items you will need to carry out this procedure:



7 Qt. pressure cooker
Large pot for boiling water (5-7 Qt.)
7 – 1 Qt. sized canning jars (w/lids)
1 cup measuring device
1 cup liquid measuring device
Industrial-grade masking tape (not shown in pic)
2 lbs or more of rye grain (rye berries)
1 gallon of spring, distilled, or drinking water

(see pic above for reference)


Initial Preparation:

Before we begin, it's always a good idea to wash your hands and clean the work space that you will be working in before you get started. However, for this procedure it's not nearly as crucial as some of the other procedures, so being overly cautious is not necessary at this point.

What is important for this procedure is to be sure that the jars that you are using are clean. If your jars are new, then it's a good idea to give them a simple washing and drying before carrying on. If your jars are used, then make sure that you get all the visible build-up eliminated and then clean them in a 10% bleach solution and rinse clean. If you don't have bleach, then you can spray lysol directly into the jar to clean it and then rinse it clean. You may want to give them a final cleaning with an alcohol-saturated paper towel to be safe.

Once your jars are cleaned, then you will need to modify the lid so that you will be able to inoculate them with a syringe needle, without having to remove the lid entirely. To do this, we will need to drill, cut, punch, or melt a hole into the center of the lid. (see pic below)


A 3/16" hole would be the ideal minimum diameter to use for this app, while a 1/4" hole would be about as large as you would ever need. I prefer a 3/16" hole as it provides plenty of room for me to get the tip in and out without much effort. Those nail-sized holes don't cut it for me (pain in the neck!)

Once you have modified all your lids to accommodate the syringe inoculation, then you can wash the lids clean and move onto the procedure.


Procedure:

Place the following items in your workspace:


7 – 1 Qt. sized canning jars (w/lids)
1 cup measuring device
1 cup liquid measuring device
Industrial-grade masking tape (not shown in pic)
2 lbs or more of rye grain (rye berries, rye grass seed, etc…)
1 gallon of spring, distilled, or drinking water

(see pic above for reference)

Now you are ready to prepare the jars of grain for the pressure cooking session.
First, scoop 1 cup of rye grain into each of the 7 jars:


Like so:


And now, using a liquid measuring device (must be a liquid measuring cup!),
pour 2/3-3/4 cup of the bottled water into the measuring device. (see pic below)


Add the water to the jar of grain:


Now, add the lid to the jar and tighten it:


Add a piece of industrial-grade masking tape over the hole (I am using hi-temp foil tape):


And shake the #### out of it until the water is mixed with the grain:


(be sure to wash off the grain that sticks to the insides of the jar by swirling the jar around until all the loose kernels have settled back down onto the bottom of the jar in one mass.) Below is a pic that shows the jar before the water is added and after the water has been added to the jar and shaken for proper mixing:


(If the jars are allowed to sit very long, the grain will soak up the water and it will appear differently than the freshly mixed one in the pic above.)

Once all the jars are mixed with the proper amount of grain and water, then you are almost ready to load them into the pressure cooker. First, we need to loosen the lids back a 1/4 - 1/2 turn to allow the jar to breathe and not blow up from pressure. Once you have loosened the lids accordingly, then you are ready to load them into the pressure cooker:


Now, you will need to boil several quarts of water in the large pot before adding it to the pressure cooker (see pressure cooker instructions for correct amount to add):


Once the water has boiled for 5-10 minutes, it's ready to add to the pressure cooker:


Now, secure the lid onto the pressure cooking unit and turn the stove top heat on "Hi":


After 5 minutes, you should begin to hear and see some steam coming out of the top hole of the pressure cooker lid. After another 5 minutes, the steam should be flowing pretty steadily, like so:


And after 10 minutes of steady flowing steam, it’s time to add the stopper thingy to the lid (total duration of time up to this point = 15-20 min):


After 10-15 minutes of the stopper being on the unit, the psi should be up to 15 psi or so and this is when you need to start the 1 hour countdown for the sterilization process to occur. The ideal range for sterilization is typically 15-18 psi for a 1 hour duration.

It’s very important to keep a very close eye on the steps involved and the duration of time spent on each step because, if you allow the cooker to run too long before adding the stopper for instance, then you will loose all the water needed for sterilizing the jars to steam, and they will dry out and get cooked or burnt! Once the cooker has reached the 1 hour mark, it’s then time to turn the stove “OFF” and let the cooker cool down on it’s own for a matter of hours.

**Never let the pressure cooker run for more than 1 and a half hours - from start to finish (the entire procedure). If you do, then you will certainly cook your grain and it will be useless.

**It’s important to mention that you will smell some grain cooking after about 15 minutes into the 15-18 psi range. That is okay so don’t be alarmed if you smell your grain cooking. ;)

After your pressure cooker has cooled back down to room temperature (at least 4-8 hours) then you can take the lid off of it and follow the procedure found below:

Checking for cracks

The first thing that you will want to do upon removing the freshly prepared jars of grain is to check the jars for any cracks that might have taken place while under the intense pressure of the cooker. You'll notice that after the jar is rotated and checked for cracks, the lid is then tightened to allow for shaking.

Shaking and Mixing

The first part of the shaking process is an effort to shake the grain loose from the jar, followed by an attempt to break the grain apart (you will notice a lot of banging and slapping going on to the jar during this part of the movie...a real good reason to check for cracks )

Rolling and Twisting

Also, notice that once the grain is broken up from the shaking and banging, a final rolling (end-over-end) of the jar is applied to help mix the dryer kernals resting at the top of the jar with the very saturated kernels resting on the bottom of the jar. This is a very important part in the shaking process because it enables the top and bottom kernals to become mixed together which allows for a complete mixing of the kernals within the jar. The idea is to flip the jar from end-to-end while simultaneaously rolling or twisting the jar around with your wrists so that the grains cascade from top to bottom, and so on...

A final smack on the bottom of the jar should cause the grain to settle back down into place which will complete shaking process and make the jar ready for inoculation.

If you take a look at the pic below, you can see how a jar grain appears directly after it's removed from the pressure cooker (jar #3) as compared to a jar that has been shaken in preparation for inoculation (jar #4).


(Notice that the grain within jar #4 has increased it's size or mass by almost 3 times the initial dry grain mass of jar #1.)

That's it! The jars are now ready to inoculate.

[Hippie3]

Grain Spawn Inoculation

Here is a list of the items needed to carry out this procedure:



Jars of prepared substrate
Spore syringe(s)
Bottle of rubbing alcohol
Paper towel
Pen marker
and
A very hot flame! (an alcohol lamp, de-natured alcohol and a shotglass, a torch lighter, etc...)

You will need to create a hot enough flame to sterilize the needle tip between inoculations or jars. For this app, an alcohol lamp is considered ideal. However, if you don't have one handy then you can compromise by using a shotglass (or similar glass object that will prove to be highly-resiliant to heat). For the process captured in the movie below, I chose a glass lid belonging to a cooking pot.

However, I prefer to use the good ol' crack (torch) lighter since it's most convenient, efficient and safe to use. I have also noticed that it reaches a higher temperature in a shorter amount of time when compared to an alcohol burner. Here's a pic of the crack torch in action:



The procedure for inoculating a jar is as follows:

1) Shake the syringe very well to agitate the spore solution within the cylinder. Check to make sure that any air bubbles are worked out of the cylinder.

2) Flame or sterilize the tip of the needle.

3) Remove the tape covering the hole in the lid and carefully insert the tip of the needle into the hole. ( steps 2 and 3 are done at the same time so the needle is still sterile when it reaches the inside of the jar.)

4) Aiming for the sides of the glass (directly above the grain), squeeze the spore solution into the jar while rotating the syringe needle around the inner jar in a circular fashion making sure to spread the solution out around the whole circumference of the jar. You will need to pay close attention not to go over 2-3 cc's per jar. You can position the syringe in your hand so that you are able to read the markings better. It may help to draw markings on the cylinder with a pen to help serve as a guide. Eventually, you should be able to just go by "feel" and come suprisingly close to the mark every time

5) pull the syringe out of the jar and recover with the tape as rapidly as possible.

6) wipe the syringe clean with an alcohol-saturated towel and set aside.

7) Mark the jar with a pen to indicate the necessary information for your reference. I usually use the following format for my jars:



ex.

Strain/Variety: GT
How many in the batch: 1 of 5
date of inoculation: 12/02
transfer or syringe: SS (spore syringe)

Now, just repeat the process for each jar until you are done.

That's it! The jars are now ready for incubation.

[Hippie3]

Incubation Chamber Assembly


Overview

Directly after the freshly prepared jars of substrate have been inoculated, the jars are then stored in incubation during the initial colonization phase.

Correct incubation consists of keeping the jars at a constant substrate temperature value of 86' f. The average time required for this initial growth phase to be completed is about 10-20 days. (see chart below for a representation of how temperature value directly affects the growth rate during the vegetative growth cycle)



There are many ways to build an incubation chamber that is capable of accomodating the initial incubation phase, but the one offered below is one of the most easiest and effective for the price and works very well for the job.

One of the most important aspects to consider when setting up an incubation chamber is the way in which it heats the substrate. Dry heat sources (such as heating pads) obtain their increase in temperature by robbing the surrounding
area of its moisture. This is very dangerous to the colonizing jars of substrate because this form of heat can easily dry up the moisture that is available in the substrate jars before the mycelium has had the chance to fully colonize it.

Radiant heat sources will not rob heat from the jars of substrate and are therefore a superior means of providing heat to the incubation chamber.


Items needed:



Styrofoam cooler ($2-$6)
50w Aquarium heater ($10)
Thermometer gauge ($2-$15)
A large glass fruit jar


Assembly:

Simply fill the large glass jug with water:



A cap full of h202 can be added:



Add the heater to the jug:



Place the jug in the Styrofoam cooler:



Adjust the timer so that it maintains a temperature range of 84’f. The substrate temperature is usually a couple of degrees warmer than the surrounding air temperature. If you are using a thermometer that has a probe for outdoor temp reading, then you should place the probe between two jars of grain so you can get an idea of the substrate temperature as well as the inside air temp. (see pic below for reference)



Once the heater is set to the correct setting, it will trickle on occasionally, as needed, to maintain the proper temperature.

During the incubation phase, if you intend to case later, the jars should be kept in complete darkness. A very limited exposure to light is acceptable when checking on growth, but the jars should never be left out exposed to light for any considerable length of time, unless you plan to grow invitro or from uncased cakes.

That's it! Radiant heating doesn't come much easier than this.

Here is something worth mentioning for those of you who may be having trouble figuring out how to get the aquarium heater temperature above the stock setting:

*Note: The aquarium heaters are set to a default setting that will only allow the element to heat up to 75-6'F. In order to make one work, you have to read the instructions that came with the heater. It explains how you must lift the dial setting knob off of the unit and rotate the exposed rod or shaft thing around and then replace the plastic knob back on to the dial. This will allow you to raise the temp to the desired setting, although it may take a few adjustments to get it set at the ideal temp range.

[eatyualive]

wow im blown away. good info!