Sorry, didn't see your post until now. :-(
I use a bit of gypsum when pouring the grains into the jars before sterilization. I don't add it during boiling like some people recommend.
My procedure:
1. Wash grains until nothing comes off anymore (takes about 4-5 thorough rinses). I like to use a huge pot. Pour in the grains, and fill with water, leaving room at the top for the water to slosh around without the grains going overboard. Use both hands and go to town, shifting and rubbing the grains in the water to wash off the crud. Pour through strainer, then back into the pot to repeat. Keep going until you are sick of it.
It helps prevent clumping, so don't cut this step short.
2. Create a 50% coffee water solution. Use a pot that can contain twice as much volume as your grains, and measure that quantity of water. Calculate half of that quantity, then measure out 14g of coffee per cup of the halved quantity of water. (To make an accurately weak coffee.) Get the water boiling, then add the coffee. Let boil for four minutes. Turn off heat. Strain out coffee grinds.
3. Add the rye berries to the coffee water, stir a bit, then cover. Let sit overnight, or about 8-10 hours. No longer than 24. We are doing two things here: (1) enfusing with coffee water, and (2) forcing the bacterial endospores to germinate, which allows them to be more effectively killed during sterilization. (If not germinated, some may survive the sterilization apparently.)
4. Check the grains at this point. If you see a small percentage of broken hulls (like 10-20%) then they are ready without further preparation. Otherwise, we need to make that happen: Boil the coffee/grain water for 15-45 minutes until the shells soften and begin to break open. Do not continue until they are mush! Check every 5-10 minutes until you see then STARTING to all break open. I stop when I'm seeing 10% of them breaking open, just enough to be noticeable. We want them to be firm, not sticky, yet soft and somewhat broken. I have found the timing on this step to be highly variable. Sometimes it's quick, and sometimes it takes forever.
5. Strain out the coffee water, rinse the grains with hot water to remove any coffee slime/starch that might cause stickiness, and let dry*. (*Just surface dry. We want these suckers loaded with coffee water, but dry on the outside to avoid stickiness.) Stirring the steaming grains in front of a fan works pretty good. (Using hot water in the rinsing step helps keep them hot and steamy, which helps remove the outside moisture quickly without losing much on the inside. Definitely do not rinse with cold water.)
6. Stir in a light sprinkling of gypsum to help keep the grains loose. I used to measure this, but started just eyeing it up. Use a tablespoon filled with it, and sprinkle around on the top until it looks lightly covered. Stir in until you can't really see it anymore.
7. Load into mason jars, about 3/4 full or a little more. (In my first round, I found that the ones loaded very high, like 90%, did not fare as well as the ones with more breathing room.) Cover with lids, four 1/8" drill holes in them, covered by synthetic filter disks. Screw on lids tightly. (Not superman tight, just not loose.) Cover lids with tin foil loosely. (Just meant to prevent water from lid of PC from dripping down onto lids.)
8. Load mason jars into PC. Fill PC with about 3 inches of water. Add a small pour of vinegar. (Just learned the vinegar trick--will stop the white crap from cementing itself on the outsides of your jars! I didn't really measure it, sorry.)
9. Sterilize those suckers! 2 hours at 15psi.
10. Take a thorough shower (I recommend exfoliating mitts and bodywash, scrub yourself from top to bottom) and get dressed in clean clothes. Or do it naked. Ha!
11. After PCing is done, keep PC sealed and let it cool down for another two hours or so. Use this time to thoroughly clean the hell out of your work area. (Turn off all airflow. Move everything off of the counter. Do first pass with bleach/water and clean rag. Let dry. Do second pass with 70% isopropyl and another clean rag. Clean all flat surfaces, walls, switches, absolutely everything in the immediate area. Bring out SAB. Repeat process with SAB, cleaning it inside and out, every single surface. Let dry.
12. Bring out your mycelium source (petri dish, master grain jar, syringe, or spore print). Sterilize it with isopropyl alcohol and put into SAB. Bring out any other instruments that are necessary. (Scalpel, inoculation loop, butane torch.) Sterilize them also and put them into the SAB. It is kind of like a safe area waiting room.
13. Check PC. If it is cool enough to easily touch with your bare hands, it should be ready. Don't do this when the grains are too hot, you don't want to kill your mycelium by mistake. Bring out your jars and load as many as you can directly into your SAB, leaving room to work. Put extra jars outside next to SAB in clean area, keeping their tin foil hats on.
14. If the jars are still too hot, wait a bit. If they are ready, begin working on the ones inside. Crack open one lid at a time, dropping in whatever source (sterilizing the transfer tool each time), and resealing the lid. Try to do this as quickly as possible, but not rushing yourself. Do it like you are defusing a bomb. Slow and steady, trying to avoid moving the air around, but as quickly as possible at the same time. There is no stopping at this point, it must be completed in one shot, or you will have to sterlize everything all over again.
15. When the jars inside the SAB are done: (1) sterilize a new set of outside jars for bringing into the SAB, then (2) move out the inoculated jars and bring in the new sterilized jars, as quickly and steadily as possible. Repeat until jars are inoculated.
16. Admire your work, and hope everything went well! Go little shroomies, grow!
