Mashing with a propane burner

Hi all,

Been reading these forums for a while. Great info! Thanks for having this site!

I have been doing the all grain brewing for a couple years now. I do single step mashing and batch sparging with mixed results. Sometimes efficiency is good, sometimes not so good. I wanted to think about perhaps fly sparging and multiple step mashing.

My question is if I decide to use my keggle to do the mash, does anyone here worry about the intense heat at the bottom of the keggle from the burner? I was also perhaps thinking about going electric and installing an element from a water heater or something like that. Same question there. I have read and read and it doesnt seem to be a concern. Is there something I am missing? I hate to ask such a noob question and a basic one at that, but I can't seem to find anyone referring to it, so perhaps it isn't an issue and more an issue of my worrying about nothing!

Thanks in advance!

Dean

There's a chance of scorching your wort, but not a big one. Most people hook up a pump and recirculate the wort so it doesn't have time to scorch.

Thanks SoCo.

A question about the use of a pump during mash. I thought the grain bed was supposed to be given a chance to settle so you can create a nice filter. Wouldn't a pump stop that from happening?

I mash in a kettle and if I have to apply heat I just continually stir. And not just swirling it around, but lifting grain from the bottom to the top, and pushing some down, and turning it over on itself.

If you want to do some serious step mashing, you should probably figure out a way to heat some water in another pot to boiling, and then add it in increments to rapidly raise to your next rest level. Using the propane to go from say a protein rest at 122 to saccharification at 152 will take a long time. Theoretically, the protein rest will continue until you're getting in the mid 130s, and that may be longer than is necessary or advised for a protein rest.

Oh, and to answer your original question, I don't think scorching is so much the concern as even heat distribution.

Groovy. Thanks Kanzi. Hadn't thought of even heat distribution. I am using one of these:

http://www.amazon.com/dp/B0009JXYQ4/?tag=skimlinks_replacement-20

The flame pattern seems wide enough. How would one go about making the distribution on this burner more even? Thanks in advance!

I use the same burner (good choice). The distribution is pretty even, as long as the air intake is adjust properly. I also started doing the heat in a kettle method and the last beer I made had to go from the 120ish rest to the 145ish rest. The best way to do it, and distribute heat evenly, is to stir and let the grains sit for a few seconds and then stir it again until you reach your desired temp and then stir somemore to make sure.

Sweet. Thanks DrawTap. So if I have this right, you stir only when raising the temps. That make a whole lotta sense. Thanks!

On the air intake adjustment - mine sounds like a jet engine and the flame is all blue with no 'no flame' space between the burner and the flame. I've always thought that was the proper flame.

Kinda correct. Whenever there is a flame on you need to stir. I take about 15 second breaks from stiring to sip my beer and rest my stirring arm. That also allows some of the grains to get a little warmer than they would if I were continually stirring, which also helps the whole pot get up to temp quicker when you do start stirring again (in my opinion).

Mine sounds like a jet engine too.

a little off from your question - but I have had terrible experiences trying to hold mash temps using my keggle on the burner. My temps are all over the place (typically end up having the burner on too long resulting in high mash temps).

If you decide to go this route over a converted cooler, I suggest doing a couple of really inexpensive brews to get it figured out. You will likely mash +- 10 degrees from where you want to be. just my $0.02

Your efficiency should be stable with infusion mashing and batch sparging. Modifying your technique may increase your efficiency but might not remove the variation.

If you do two batches with the same grain bill and the same water ratio and same mash temperature, do you get the same efficiency? There is some variable from batch to batch that is causing a varying efficiency, that could be unrelated to the things you're thinking of changing.

Could be mash pH. Maybe your sparge temperature varies from batch to batch. You probably use a different mash thickness depending on grain bill size. Any of these could be contributing to your issue, and none of them would be solved by step mashing or fly sparging.

DrawTap88 said:

Kinda correct. Whenever there is a flame on you need to stir. I take about 15 second breaks from stiring to sip my beer and rest my stirring arm. That also allows some of the grains to get a little warmer than they would if I were continually stirring, which also helps the whole pot get up to temp quicker when you do start stirring again (in my opinion).

Click to expand...

There is no reason that letting the grain sit every 15 seconds would heat the pot quicker than continuously stirring. Maaaaaaaybe the stirring means you lose a little heat through the continual exchange between grains and kettle wall, and then kettle wall and air, but I can't imagine it would be so drastic you would actually notice it.

I always stir continuously if the flame is on - I want to minimize denaturing of enzymes by slowly raising the temp of the entire mash, not just the grains at the bottom of the kettle.

ksbrain said:

Your efficiency should be stable with infusion mashing and batch sparging. Modifying your technique may increase your efficiency but might not remove the variation.

If you do two batches with the same grain bill and the same water ratio and same mash temperature, do you get the same efficiency? There is some variable from batch to batch that is causing a varying efficiency, that could be unrelated to the things you're thinking of changing.

Could be mash pH. Maybe your sparge temperature varies from batch to batch. You probably use a different mash thickness depending on grain bill size. Any of these could be contributing to your issue, and none of them would be solved by step mashing or fly sparging.

Click to expand...

Haven't done the same grain bill or water ratio, so I am not sure there. I use one of those Excel spreadsheets to calculate the amount of water to add and the temps. Something I read that I had not done before but did do on this last batch was when I did my final rinse, I used water that was 170F instead of a calculated water temp that would have kept my mash at 152F. I also let it sit for 10 min with the 170F water in the cooler but that shouldn't affect efficiency, should it? I am pretty anal about keeping notes that include temps and gravities and all so I can repeat the results. This batch happened to be the first time I did the 170F mash out (that's right, right?) and noticed lower efficiency. Grain bill was 8lb Pilsner malt, 2lb wheat and 1lb German munich. Wound up with an efficiency of about 60%...

Hold on. I am totally stupid. I went back and figured my efficiency again and I had calculated it wrong. I am an idiot. I had 75% efficiency on this batch not 60%. Good Lord... I recently bought enough grain to do four batches so I could have about 20 gallons of beer on hand for New Years. With my trying to be efficient at filling out my worksheets, I neglected to clear out one of the ingredients and it showed I had 2 more lbs of grain than was actually used for my Kolsch-like recipe. Derf... Hence the lower efficiency calculations.

I need a beer....

Thanks everyone! Perhaps I will stick with my original methods!

i direct heat my keggle mash tun and use a pump. there is a gate valve connected at flow out of pump, ball valve out of keggle with a line connecting to the pump. i turn the burner on low to maintain temp, slightly crack open the gate valve flow out so not to creat suction and compact the grain bed. from the gate valve out i run i line back in the top if the keggle. it works good for me, ive done 3 batches this way so far.

i don't just crank up the heat, just slighty adjust the flame and leave the pump running the whole time to recirculate.

phatuna said:

a little off from your question - but I have had terrible experiences trying to hold mash temps using my keggle on the burner. My temps are all over the place (typically end up having the burner on too long resulting in high mash temps).

If you decide to go this route over a converted cooler, I suggest doing a couple of really inexpensive brews to get it figured out. You will likely mash +- 10 degrees from where you want to be. just my $0.02

Click to expand...

Yeah, sounds to me like more trouble than it is worth.

kanzimonson said:

There is no reason that letting the grain sit every 15 seconds would heat the pot quicker than continuously stirring. Maaaaaaaybe the stirring means you lose a little heat through the continual exchange between grains and kettle wall, and then kettle wall and air, but I can't imagine it would be so drastic you would actually notice it.

I always stir continuously if the flame is on - I want to minimize denaturing of enzymes by slowly raising the temp of the entire mash, not just the grains at the bottom of the kettle.

Click to expand...

Geez. The coffee didn't work today. But let's try it again. I'll stir continuously for a few minutes, let it sit for 15 seconds to warm the grains on the bottom of the pot. When I pull those grains up to the surface, in theory, they will warm up the cooler water nearer the top of the kettle, which helps even out the temp throughout the mash.

Sorry. I know I'm not explaining myself great right now, but I hope that makes sense.