blue helix's spawn bag tutorial
Posted 11 April 2006 - 10:16 PM
To start to use spawn bags, I recommend three things (a) the bags, (b) an impulse sealer, and © a hot glue gun. The best inexpensive bags that I have found (30 cent a piece for 100) can be found through the Spore Works catalogue (not the web store but through their catalogue only) here:
Look for "Large Autoclavable Gusseted Bulk Spawn Bags".
For 60Hz/120V power, the impulse sealer is best purchased through Ebay. You want one that produces at least a 2mm-to-3mm-wide seal and is 12" long. Although you can get away with an 8"-long one, it's easier to use a 12" or 16"-long one in case the flaps aren't perfectly aligned out of the cooker. It'll end up about $20 to $30. Here is an example auction for a 12"-long one that is perfect for the task:
The last item I recommend is a hot glue gun. Hot glue allows you to re-seal and sterilize the hole after a huge LC injection. It's the most inexpensive way to reseal the hole. You don't have to use hot glue, of course, but that's how I do it and find it works well. You can find a hot glue gun just about anywhere. They sell them at dollar stores for a $1 or you can buy a nicer one at Wal-mart for $5 to $10. They all work about the same except some won't burn you if you touch the tip and some handle hotter glue than others. Any will work fine.
Posted 11 April 2006 - 11:01 PM
A blob of silicone adhesive on the bag makes for a nice/cheap self-healing injector port (Hippie3 gave me that one).
I had a problem with hot glue coming loose over time. Do you use standard glue sticks?
Two thumbs WAY up for mentioning eBay as a source for Impulse sealers. FOAF got an 18 incher (with a rebuild kit) for $28. If you know what you want and what it's worth, you can get some insane deals on eBay. Unless you get "bidding mania" that is. Sadly, I speak from experience on the topic of bidding mania...
Posted 12 April 2006 - 12:22 AM
As for the best bags for me, I am rather split between the 60-cent bags with the superior plastic and filter patch like those Fungi Perfecti sells and the cheapest 30-cent bags that Spore Works sells. The cheapies work okay but just don't have quite the quality plastic and filter patch of the more expensive ones (and they are a tiny bit smaller). If you are working with sharp stuff like woodchips, the cheaper ones can puncture more easily during the kneading step. Another thing that differs a lot between the two bags is the filter patch. The cheaper bags must be treated with a lot of respect because if the patch gets wet and you touch it, the bag is basically toast. The more expensive ones seem to resist this vector of contamination better. In any case, I take care to never touch the filter patches regardless of the bag and keep the patch dry at all times. For example, when you are injecting the LC, take care to not squirt it directly on the inside of the filter patch; that's just asking for trouble and I contaminated a bag that way.
I have been using hot glue for some time and it will not come loose using it the way I recommend. First, I do not recommend ever using hot glue directly on a spawn bag. Some types of hot glue with some types of bags will melt the bags! I recommend one always makes a tape-based injection platform to poke through and put the hot glue on and protect the bag. Mine consists of two types of tape.
Directly against the bag, I first stick a small square patch of heavy duty duct tap--buy the good stuff. Over the duct tape I put piece of heavy duty masking tape. The duct tape alone softens in the heat of pressure cooking and will stick to the side of the cooker if pressing against it while the masking tape alone is pretty weak and doesn't stick too well directly to the bag. The two together, though, make a perfect team with the duct tape providing the heavy grade thickness and stick while the masking tape keeps the duct tape from sticking to the walls of the pressure cooker during cooking. I have used these two together for dozens of spawn bags, and it works great every time. No matter how violent I get with the kneading, I never have had the hot glue come off, although one time I actually broke open a bag because I was drunk. I have an attached picture showing what it looks like once the tape platform on the spawn bag been injected and re-sealed with hot glue.