A little while ago, when making a starter for my blonde ale, I had yet another boil-over...
My procedure was pretty standard; add some DME and water to a 2000ml Erlenmeyer flask and boil on the stove for 15 minutes or so. I'd then cool the wort using an ice-water bath, pitch my yeast, get it going on my stir-plate, and clean up. Start to finish this would normally take 30 to 45 minutes. I don't know what I've been doing but, lately, I just can't seem to avoid boiling over. I end up making a complete mess of my stove and add an extra 15 minutes to clean everything up. I even started using foam control to lessen the chances of a boil-over but still seem to screw it up. (I think the problem may have something to do with keeping a steady temp on my electric glass-top range.)
At any rate, that last boil-over prompted me to pick up a pressure canner
and a couple of cases of mason jars
(about $9/case at my local ACE hardware). I had heard some mention of canning starter wort on The Brewing Network
. It sounded like a great way to save some time and also avoid the dreaded boil-over. Another great resource I came across when searching the topic online was Drew Beechum's article, "The Starter Made Easy"
. [Edit: Forgot to mention Bugeater's forum post
. Lot of good info there as well. Thanks Wayne!]
Last night I finally got some time to try it out. I probably could have saved time by filling a few jars with DME and water and just processing that one batch but I decided to go all-in. I ended up mashing 8 pounds of 2-row at 150°F and pulled off 7 gallons of 1.038 wort. This was enough to fill up all of my 12 half-gallon jars and another 4 quart-sized jars.
With my new Presto 23-Quart Pressure Canner ($79 shipped from Amazon
), I was able to process 2 gallons of wort at a time (4 half-gallon jars). Even though they're only processed for 15 minutes at 15psi, each batch took a considerable amount of time...
- boil 10 minutes to evacuate all air from canner
- place regulator on vent to bring up to pressure. ~5 minutes.
- process @ 15psi for 15 minutes
- take off heat and allow to cool. This took about 45 minutes.
I had 4 batches to process because I had an extra 4 quarts more than I expected (mash efficiency was about 80%. Up from 75%.). That's about 5 hours just to can everything. The whole process including clean-up took me about 7 hours. I ended up with enough for 14 two-liter starters. (A good year of brewing for me.) If you figure 30 minutes to make a starter on the stove, it would add up to 420 minutes. 420 minutes = 7 hours!!! I guess I broke even... but no boil-over!! Plus, I'll be able to make a starter at the drop of a hat. Just pop the lid on one of my jars, dump into a sanitized flask, pitch the yeast and place on stir-plate. Nice!
Some info on pressure-canning:
When pressure canning low-acid foods such as wort, it is important to follow proper canning techniques. Jars must be processed for 15 minutes at 15psi (250°F).
Failure to do so may result in death!
The pressure-canning process is relatively simple but it's extremely important to follow it exactly. The problem is that wort is a low-acid food and the canning process removes all oxygen. What you're left with is a low-acid, anaerobic environment rich in nutrients... the perfect environment for the bacteria Clostridium botulinum
to grow. As botulinum grows it creates nasty neurotoxins that can cause botulism
. Spores of this bacteria can survive temps of up to 240°F. If you're not careful to keep your canner at the correct pressure for proper amount of time, you could end up with the botulinum toxins in your starter wort. Bad news!
is the most acutely toxic substance known with a median lethal dose of about 1 ng/kg
(1 part per trillion) (intravenously) meaning one teaspoon can kill 1.2 billion people."(I'm quoting Wikipedia here so it must be true.)
Per DrYeast on The Brewing Network's forum:
"There's an easy way to tell if your food poisoning is botulism or not.
Quick onset, cramping, liquid out of both ends, want to die = not botulism.
Slow onset, paralysis and death = botulism."
NOTE: During the normal brewing process, the fact that botulinum spores may survive the boil isn't that big a deal. The spores cannot grow in an aerobic or acidic environment. As the yeast ferments the beer it may use up oxygen but it also increases alcohol and reduces the pH enough to inhibit the bacteria's growth. Again, it's the growth
of the spores that create the toxins.
Not so easy when taking a picture.
With 4 half-gallon jars.
Before and After Processing
Follow Up: Making a Starter from Canned Wort