Recirculation issues with eBIAB

[mcgster]

Just curious if anyone else has run into any issues recirculting their eBIAB setup.

I have a 100L BIAB setup with a bag that I picked up from Jimmy. There is a false bottom at the bottom of the pot to keep the bag off of the element (5500W ULWD Camco). I have a recirculation pump that is throttled on the output and I restrict the flow to about 20% of the normal output.

Last night when I was brewing up a new recipe the bag was continually creating suction against the false bottom in between stirring (I usually stir about every 5 minutes). Even with the flow restricted to as low as I could go (and maintain line pressure). I didn’t think too much of it until about halfway through the boil I noticed a strong burnt tobacco smell / taste in the wort.

At some point in the mash the suction must of created an airspace around the element and caused some carmelization. I continued with the boil and… well… I’m sad to say that no amount of hops can mask the burnt taste of this wort.

I have noticed the bag creating a suction every other time I have used it but I have never had any carmelization like this. Has anyone else run into this issue?

Thanks!

[GuingesRock]

I had trouble re-circing a weizen because of the wheat malt in there which has no husks.

Sorry to hear about the brew.

[mcgster]

Thanks me too I was very excited to try the recipe... Now I'm going to submit it as a specialty beer... Burnt tobacco IPA

[mcgster]

Here is the element post boil. I soaked it in PBW overnight and it's still caked on!

ImageUploadedByTapatalk1406727906.230516.jpg

ImageUploadedByTapatalk1406727915.844424.jpg

[jtmwhyte]

I burnt the crap out of an element with rye malt a couple of months ago. I used a dremel with a wire brush to clean it up.

[Jimmy]

You're likely going to have trouble recirculating with the BIAB, though there are people who have done it (not me). The voile material is so fine that speed at which it drains is likely going to be slower than your recirculation. Is there any particular reason you really want to recirculate during the mash? I don't really think you'd be gaining much, if anything, from the recirculation.

[RubberToe]

If you search the forum you should find posts from me about the same thing. I do single infusion with my BIAB these days with better results. Don't worry about your temp dropping too much just try to hit your numbers on mash in. Step mashes are out.

In order to recirc decently you'd need a coarser bag and a coarser grain crush.

[mcgster]

You're likely going to have trouble recirculating with the BIAB, though there are people who have done it (not me). The voile material is so fine that speed at which it drains is likely going to be slower than your recirculation. Is there any particular reason you really want to recirculate during the mash? I don't really think you'd be gaining much, if anything, from the recirculation.

I guess the only reason was to maintain the temp and ensure an even mixing, i was worried about temp stratification and i'm used to doing HERMS. I really flipped to BIAB on a whim (since all i needed was the bag) and really liked the quicker brew day that came with it.

Do you run your element at all during the mash, or just insulate?

[mcgster]

If you search the forum you should find posts from me about the same thing. I do single infusion with my BIAB these days with better results. Don't worry about your temp dropping too much just try to hit your numbers on mash in. Step mashes are out.

In order to recirc decently you'd need a coarser bag and a coarser grain crush.

I have a 1500W drop in element for my smaller system, what about dropping that directly in with the grain and running it through the PID?

I may be putting too much concern on maintaining a stable temp but i'm always trying to maintain consistency in my batches and temperature stratification does concern me.

[RubberToe]

I'm not sure if I'd try that, it would probably scorch as well, especially since it would take longer for the temp probe to read the change.

Do you insulate your kettle?

[mcgster]

I don't currently as i have always recirculated.

I have reflectix wrap laying around from my old mash tun. I'll have to rig it up again.

[RubberToe]

Got any pics of your 100L setup?

[mcgster]

ImageUploadedByTapatalk1406735240.278763.jpg

ImageUploadedByTapatalk1406735255.361807.jpg

[mcgster]

Those are just two from last night, i have more in better light i just have to track them down

[mcgster]

I find it hard to believe but i don't have any pics of the whole setup.

Here is the kettle, its a Concord 100QT with a 1.5" TC connector silver soldered in the back and a 1/2 welding spud in the bottom

IMG_1311.jpg

The controller is pretty basic, it was my first attempt at wiring up a PID

IMG_0458.jpg

[GuingesRock]

You don't have to insulate a full volume mash of that size. It cools very slowly because of the large volume. I've argued before that's an advantage. Anyway, I never insulate.

http://www.brewnosers.org/forums/viewto ... 607#p63434" onclick="window.open(this.href);return false;

I only tried to recirculate once with full vol. mash, and that was with the weizen ...trying to step mash it. Didn't work. That was with a Blichmann false bottom and no bag, no element though, on the stove hotplate.

[mcgster]

When I get back from my trip I'm going to brew a triple batch and I'll check the temp every five minutes to see if I get any drop. I'll post what my results. I'm going to rig up some reflectix wrap in case I do see the temp dropping. If it doesn't drop by more than a degree or two I won't need it.

[GuingesRock]

When I get back from my trip I'm going to brew a triple batch and I'll check the temp every five minutes to see if I get any drop. I'll post what my results. I'm going to rig up some reflectix wrap in case I do see the temp dropping. If it doesn't drop by more than a degree or two I won't need it.

My full volume mash, with 17 gals of strike water at 159.6 and a grain bill of 23.5lbs, gives an initial mash temp of 154F and drops to 146F after an hour in the kitchen which is at 20C. That’s in a 20 gal Blichmann boilermaker SS pot with no lid on and no insulation. That’s the way I like doing it, probably just because I like to be different.

I compared this method to an identical mash which was insulated and the efficiency was identical. I documented it all on BIABrewer when I was on there (Australian BIAB site)

[mcgster]

How does your final gravity match up with the predicted final gravity. I wonder if beta amylase is kicking in at the end of your mash to convert some of the non reducing ends of the starches. When you enter your mash info it always predicts your FG based on the initial mash temp unless you specify a step mash.

[GuingesRock]

From back in the day. I had only been brewing for three months. Long thread "Free Range Mash Experiment" with all my arguments, but the figures are in this post: http://www.biabrewer.info/viewtopic.php ... =25#p26812" onclick="window.open(this.href);return false; That was a 5 gal batch BIAB brew.

I was so proud when I got this post from Joshua, one of the mods on that site.

Guinges, Well Done, Sir, Well DONE!!

That was 18 months ago. I have been doing "free range mashing" ever since. I have my BS tuned to predict fairly accurately.