Fly Sparge: To stir, or not to stir

I've had some conflicting info lately. I fly sparge with a keggle MT setup (false bottom with dip-tube). My problem has been that I am still running into hot and cold spots at about 30-45 mins into the mash. I have 3 layers of reflection wrapping the sides, bottom, and top.

I stir like he'll for about 3 mins before closing everything up for the mash.

Should I be stirring the mash half way through to make sure the temp is even in the MT? I generally do 10 gal batches.

I've always been told to not stir so that the grain bed can settle... I've also read that I should give it a good stir a few times (once or twice) during the mash. I do not intend to stir while spraying (fly),.which makes sense to me.

So, to stir or not to stir. That is the question!

Cheers

Stir Sir!

Not saying it's right, but I stir the mash 2-3 times during the mash.

I wouldn't worry about the grain not settling if you stir at the half way point, but I have never done it. I stir before I start and that's it. But I wouldn't see why there would be any issues doing it again. Aside from loosing a little heat possibly. Don't know how much you would lose though. But I doubt it would be worth worrying about.

Even when fly spraying?

I'm gonna brew around the 15th, so I'll give it a go.

If you are questioning whether or not to stir DURING the fly sparge the answer is you DO NOT. Stirring defeats the purpose of fly sparging

Actually you can (and should) stir the top 2-3" of the mash. As long as you don't disturb the grain bed filter you won't hurt anything.

I stir mine 2 or 3 times real good for just 30 seconds or so to make sure I get out all the good stuff just like dipping a tea bag in hot tea to get all that tea from the bag. then let it set for the last 30 minutes maybe without so it settles down . It will settle anyway when you start draining that tun. It has no choice . I drain mine almost dry sometimes and that makes a solid bed and takes a while to get that sparge water into it .

On a side note,are you planning on doing a mash out after done mashing? Depending on your mash, if you don't recirculate, which it seems you have a simple mash, some people (me also, but I batch sparge) add enough boiling water to raise the mash temp to around 170F, stopping the enzymes and lowering the viscosity of the wort so that it will flow easier. It may help efficiency with super high gravity wort. You're basically just getting the mash ready to sparge, since you are done converting starches.

I would guess you'd have to stir that, then just let it settle for a few minutes and then sparge?

I never really thought about NOT stirring it, I wouldn't think it would take that long to settle - maybe you're over thinking it?

I've never stirred during my mash but I do stir when conversion has completed and just before vorlauf. Then I let everything settle down and fly sparge for about an hour without disturbing the grain bed further.

Awesome advice. I think I am definitely over thinking it... Will try next week. Yay brew day!

I've always stirred my mash every fifteen mintues to help avoid having hot/cold spots and so that I can check the temp to make sure it's not dropping too much. I also preheat my mash tun with a half gallon of boiling water. My temp only drops a degree or two with all my stirring and temp checking and I get around 80-85% effciency. The vorlauf step is where you'll really get the grain bed working into a filter so as long as you recirculate well enough to clarify the wort then I'd say stir away brother man.

Stir...mash mixers were invented for this very purpose....just recirc enough at the end to establish the grain bed and clear the run off.

I'm the odd guy out. I don't stir. When I start draining the MLT, I have the the fly sparge going, I always have 2" of water on top of my grain. The grain is like a filter in revers.

i use a 10 gallon cooler as my mash tun. i stir really well at the beginning then i just watch what the temp is doing. if you are a few degrees hig open it up and stir away. i will also stir once or twice if my temps are right on if i feel like it. if i shot low then i just leave it alone.

either way stirring should not make any difference as far as the grain bed goes during the mash. after you are done with the mash you should be recircing some of the mash either with a pump or by draining some of the wort off them gently dumping ot back on top of the grain bed. you do this until it runs clear and then you start your sparge. you should be doing this regardless of if you stir your mash.

Fatt said:

I've always stirred my mash every fifteen mintues to help avoid having hot/cold spots and so that I can check the temp to make sure it's not dropping too much. I also preheat my mash tun with a half gallon of boiling water. My temp only drops a degree or two with all my stirring and temp checking and I get around 80-85% effciency. The vorlauf step is where you'll really get the grain bed working into a filter so as long as you recirculate well enough to clarify the wort then I'd say stir away brother man.

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I fill my tun up with hot water in the bath tub while I am tending to the other operations so it warms up a bit or set it outside in the sun in summer . If not it sure does drop several 5 or more degrees in the winter as it is stored in a cold closet.

I have a direct fire rims and recirculate the whole time and stir throughout the mash. MY theory is it keeps heat/ enzymes evenly dispersed throughout the mash.
I also stir the top few inches during fly sparge (after bed is fairly established) to make sure there is no channeling going on. I get 84%eff. every time.

Well, I guess I'll stir it up, Just like Bob Marley said. Thanks everyone!

mbobhat said:

On a side note,are you planning on doing a mash out after done mashing?

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Noob question but how does one mash out while fly sparging? Thanks

Edit: I am using coolers for HLT and MT. So I'm just not sure of the next step after draining the HLT during my fly sparge.

I would ask the fly spargers, I cannot speak to if they use this process or not. You can forget about it probably, from my little searching:

https://www.homebrewtalk.com/f36/mash-out-fly-sparging-182465/

millsbrew said:

Noob question but how does one mash out while fly sparging? Thanks

Edit: I am using coolers for HLT and MT. So I'm just not sure of the next step after draining the HLT during my fly sparge.

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Mash out is before sparging. You need to bring the mash up to about 165-170F by adding a calculated amount of near boiling water and stirring it in before fly sparging.

Or install a RIMS or HERMS system...

You don't have to do it, but you should probably start with hotter sparge water in that case, so that the grain bed temperature rises high enough during sparging.

millsbrew said:

Noob question but how does one mash out while fly sparging? Thanks

Edit: I am using coolers for HLT and MT. So I'm just not sure of the next step after draining the HLT during my fly sparge.

Click to expand...

Their are a LOT of ways to do this, ask a different brewer, get a different answer. Also, different beers may mash out at different temperatures or processes. I pump in 180* sparge water that mixes with the top layer of water in the mash tun and slowly raises the temperature of the mash. Some times I don't mash out.

I heat my sparge water up to about 190.

Thanks for the replies. I was incorrectly under the impression that the fly sparge water was at the same temp as the original mash-in temp.