No preboil, just sulfite
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No preboil, just sulfite
So I wanted to do a small pilot experiment investigating whether it would be possible to eliminate the preboil step and just rely on sulfites alone to remove the oxygen from the strike water.
Because my DO meter is only rated to 122 degrees F, I heated 2 liters of water to slightly below that temperature in a saucepan.
Then, I measured the initial DO content to be 8.13 ppm.
Next I measured out 130 mg/l of SMB, or 260 milligrams
Because my DO meter is only rated to 122 degrees F, I heated 2 liters of water to slightly below that temperature in a saucepan.
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Then, I measured the initial DO content to be 8.13 ppm.
- IMG_0735.JPG (77.38 KiB) Viewed 7207 times
Next I measured out 130 mg/l of SMB, or 260 milligrams
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Last edited by Techbrau on Sun May 08, 2016 2:48 pm, edited 1 time in total.
If you always do what you've always done, then you'll always get what you've always gotten.
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Re: No preboil, just sulfite
As soon as I added the sulfite I gave it a quick stir to distribute it uniformly, and then set a timer going. I measured the DO once every minute.
1 minute in
2 minutes in
3 minutes in
1 minute in
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2 minutes in
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3 minutes in
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Last edited by Techbrau on Sun May 08, 2016 2:57 pm, edited 1 time in total.
If you always do what you've always done, then you'll always get what you've always gotten.
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Re: No preboil, just sulfite
I missed the measurement at 4 minutes because I was taking my lunch out of the oven. Anyway, here's 5 minutes:
6 minutes
7 minutes
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6 minutes
- IMG_0740.JPG (89.33 KiB) Viewed 7206 times
7 minutes
- IMG_0741.JPG (86.97 KiB) Viewed 7206 times
If you always do what you've always done, then you'll always get what you've always gotten.
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Re: No preboil, just sulfite
8 minutes
9 minutes
10 minutes
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9 minutes
- IMG_0743.JPG (82.43 KiB) Viewed 7204 times
10 minutes
- IMG_0744.JPG (96.08 KiB) Viewed 7204 times
If you always do what you've always done, then you'll always get what you've always gotten.
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- German Brewing
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Re: No preboil, just sulfite
Okay, so after 10 minutes we got down to 1.15. I decided next to see what would happen if I splashed the water a little. So I poured it from a height of about 5 inches into another pot, then measured the DO
So how long is it gonna take us to get under 1 ppm? I waited another 10 minutes after this point (20 minutes total) and took another measurement
Hmm. Why is it so high? I wonder if we've already used up a lot of our sulfites, so let's measure that
Wow, down to less than 50 ppm. We started with 130 * .76 = 98.8 ppm, so we just used up more than half of it. At a little over 1 ppm DO left and with the reduced sulfite concentration, it doesn't look like it can reduce oxygen faster than it's diffusing in at this point. It's possible that we would have gotten below 1 ppm if I hadn't poured the water, so that may need some further investigation.
So obviously this a little pilot experiment and it isn't a full scale mash. However, I think it suggests something very important:
SULFITE IS NOT A CURE-ALL MAGIC BULLET!
You can't just add some fairy dust to your water and expect it to keep your mash and boil under 0.5 ppm DO for 3 hours straight. Henry's law is a bitch, and the lower your DO levels become the faster more oxygen diffuses in. You need to win the battle on EVERY FRONT and your system is only as good as the weakest link in the chain. For me, this means preboil, high sulfite dose, NO splashing or leaky hoses, no copper/iron/manganese etc in the water and some sort of inset lid or mash cap with as little headspace for air as possible.
- IMG_0745.JPG (83.2 KiB) Viewed 7204 times
So how long is it gonna take us to get under 1 ppm? I waited another 10 minutes after this point (20 minutes total) and took another measurement
- IMG_0747.JPG (87.86 KiB) Viewed 7204 times
Hmm. Why is it so high? I wonder if we've already used up a lot of our sulfites, so let's measure that
- IMG_0748.JPG (79.96 KiB) Viewed 7204 times
Wow, down to less than 50 ppm. We started with 130 * .76 = 98.8 ppm, so we just used up more than half of it. At a little over 1 ppm DO left and with the reduced sulfite concentration, it doesn't look like it can reduce oxygen faster than it's diffusing in at this point. It's possible that we would have gotten below 1 ppm if I hadn't poured the water, so that may need some further investigation.
So obviously this a little pilot experiment and it isn't a full scale mash. However, I think it suggests something very important:
SULFITE IS NOT A CURE-ALL MAGIC BULLET!
You can't just add some fairy dust to your water and expect it to keep your mash and boil under 0.5 ppm DO for 3 hours straight. Henry's law is a bitch, and the lower your DO levels become the faster more oxygen diffuses in. You need to win the battle on EVERY FRONT and your system is only as good as the weakest link in the chain. For me, this means preboil, high sulfite dose, NO splashing or leaky hoses, no copper/iron/manganese etc in the water and some sort of inset lid or mash cap with as little headspace for air as possible.
Last edited by Techbrau on Mon May 09, 2016 6:50 pm, edited 2 times in total.
If you always do what you've always done, then you'll always get what you've always gotten.
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Re: No preboil, just sulfite
Nice experiment. I've often wondered if a larger dose would enable us to skip the preboil.
- Owenbräu
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Re: No preboil, just sulfite
Well ain't that just a PITA....
Also suggests to me that you need to get the SMB into the water very shortly after boiling and limit the headspace in the HLT with a tight fitting cover.
Also suggests to me that you need to get the SMB into the water very shortly after boiling and limit the headspace in the HLT with a tight fitting cover.
Last edited by Owenbräu on Sun May 08, 2016 4:12 pm, edited 1 time in total.
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Re: No preboil, just sulfite
This is fascinating stuff!
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