Burnt/Scorched Wort - Needing some help

[lalh20]

Bear with me, I'm losing my mind a bit here. I searched and read several "scorched" threads but none seemed definitive as if someone identified the issue and permanently fixed it.

I just kegged a batch that clearly has a scorched and burnt flavor. This is the second time this has happened this drastically (I had another with a very slight scorch taste) and I can't single out how to prevent it.

The biggest issue is that I've brewed probably 40 batches on my system now, and only 2-3 have had this issue. I can't point out any specific/unique ingredient or step that was different in my process and on this batch I was actually intentionally careful.

My system is a 240V EBIAB that I made myself. Kettle is a keggle with a camco 5500 ULWD element and I have a false bottom above it (it's a stainless plate that is WELL ventilated, I'll post pictures if someone wants to see it - holes are 1/2 in to 3/4 in size all over it no more than 1/4 apart between holes). The keggle is upside down with the drain in the center (out the SANKE port) and I recirculate for the entire mash and boil. My pump is a chugger that I run at around 60% probably higher the entire time (cavitates if i run all-out).

The last batch i limited the power output to 70% at the highest point (even when ramping up to boil) just out of fear of scorching.

I use a hop spyder (nylon hop sock suspended from a stainless tub, never touches the element due to false bottom).

I've had three batches in between the last scorched batch and this one. I can't pinpoint a reason why THIS batch scorched.

Ingredients:
23 lbs 8.0 oz Pilsner (2 Row) UK (1.0 SRM) Grain 1 85.0 %
4 lbs Munich Malt (9.0 SRM) Grain 2 14.5 %
2.5 oz Caramel/Crystal Malt -120L (120.0 SRM) Grain 3 0.6 %
1.00 oz Magnum [10.80 %] - Boil 60.0 min Hop 4 19.3 IBUs
1.50 oz Galaxy [18.10 %] - Boil 20.0 min Hop 5 29.4 IBUs
1.50 oz Galaxy [18.10 %] - Boil 10.0 min Hop 6 17.6 IBUs
3.75 oz Galaxy [18.10 %] - Steep/Whirlpool 10.0 min Hop 7 22.0 IBUs
3.75 oz Galaxy [18.10 %] - Dry Hop 3.0 Days Hop 8 0.0 IBUs

Can anyone pinpoint what would cause this? I will go crazy if I have to assume this is a "random" issue and can't identify and avoid the cause.

There was a VERY slight amount of hop addition that missed the hop sock this time. could that cause it? I actually think I've done hop additions in the past that never made it into a sock so I doubt it. a long time ago I even had a hop sock that burnt from the element (pre-spider) and leaked hops out - no burnt flavor in that batch.

Help please!

 

[BrunDog]

I’ll start with the most basic question... is the element clean? I mean really clean?

 

[andrewmaixner]

I only had to dump one batch -- even 6 months of aging did not change the Ash aroma -- but had a burnt crust on my straight element in a couple other batches, before i did these two things:

1) Element straight or ripple? even they they call them ULWD, the ripple has only 50% the watt density of the straight 5500W element. I moved to a ripple.

2) I had problems recirculating when I used a mesh bag, it would not recirc fast enough (bag would seal against sides of kettle, leaving only the bottom for liquid to escape) and the element and temp probe would be uncovered, then heat up and and scorch. Then it probably kept getting even more burned through the boil.

After I moved to a stainless mesh basket (guaranteed 100% of the surface area allows liquid to flow through) and ripple element, have not had the issue since.


I don't bag bittering hops, ever, so that should not be an issue. I only bag when it's a super-hoppy IPA, so I lose less volume.

 

[lalh20]

Yes, it is a ripple element.

Regarding the recirc, I may be a bit different than most but I don't recirculate through the bag most of the time. I usually put the hose beside the bag just so that I don't have an issue with recirculation speed. Usually for 5-10 minutes Ill recirc through the bag only so I can make sure all the grain is well saturated, but when I do it I'm standing right there making sure the water outside the bag isn't dropping much at all - as soon as I see it going down (low flow through the bag) I move it back outside.

Regarding cleanliness of the element, another crazy thing...in all the batches up until the first scorch, I didn't make it a practice to do any more than hose down the element. Since the first scorch however (probably 30+ batches in) I've taken to scrubbing the element down. This time is was fairly clean at startup (I say fairly because I can't say that I've gotten every single spot).

 

[mabrungard]

A commercial brewery located near me, had this sort of problem. They ran a 5 bbl electric brewery and I started noticing roasty, smokey flavors in all their beers. It did turn out that they weren't scrubbing the elements clean after each brew and the wort was burnt onto the elements and imparting flavor. Their beers returned to normal after a proper cleaning.

All elements MUST be free of any coatings or films or that organic matter will eventually burn. A hot PBW soak should take the burnt residue off the elements. But in the future, all it takes is a thorough wiping and washdown to get residue off the elements when you do it regularly. I wipe down all the elements in my system after each brew day.

PS: You often can't see the dried organic layer on your elements, but I find that I can feel it when its still wet. Its more slippery than metal.

 

[BrunDog]

Or just replace the element.... they are cheap enough!

 

[lalh20]

Yes, replacement may be the way to go.

If after that I quickly end up with another scorched batch, my next post may come from the looney bin!

My other thought was that maybe I should set up my recirc so it always pumps back in right by the element. What do you all think of that? I could guarantee good flow doing that, but the sacrifice would be I'd have to rely on handpower more for stirring the mash and might lose a bit of "flow" in the mash itself.

 

[lalh20]

Update here - after reading tons of other posts on this matter I figured if I'm planning to replace the element, what would it hurt to dry-fire it like some others have said they do to clean it. Also, I was kind of interested in looking for "hot spots" on it to see I could pinpoint where it was scorching.

The process was simple enough - turn the element on with no water for roughly 15 seconds, then I did shorter 5 second bursts to warm it slowly. Within less than a minute smoke was rolling out of my keggle. After letting it clear and doing the process a few more times (stopping when I could see that the element was glowing red-hot) the element looked much cleaner and stopped smoking fairly quickly.

I let the redness really glow and got it pretty hot, it was very clear that this cleaned ANYTHING that was on it off. Also, the nice thing about it getting red-hot is I could visually see that there were no glaring hot-spots (it was very slightly brighter at the first bend and just after the bend at the tip, but didn't look significant).

Bottom-line, this process worked well enough that I'm 100% sure if I keep using it I can rule out all possibility of a dirty element causing the issue.

Now that I know I can safely dry-fire my element (to an extent) I plan to continue with this same element indefinitely to see if the problem is eliminated or returns. I promise to report back with results over time and hopefully put this nasty issue to rest for good. Maybe this solution will be the same one everyone else with this problem finds out is a permanent fix!

(I did order the extra element to have on hand just in case).

 

[wilserbrewer]

I would remove the false bottom for the boil as it may trap a lot of debris and trub that is prone to scorching.

Ime I feel it is the protein trub that scorches, and a FB may keep a heavy concentration at the element.

Give the kettle a few good stirs when ramping from mash to boil to help suspend the trub so it doesn't make a trub soup around the element.

My only scorch was when I paused the boil to run a few errands, my guess is that the trub settled and scorched.

 

[LarMoeCur]

Even at 60% that Chugger pump is creating a vacuum under the false bottom. I'll bet the wort is draining below the element. It only takes a fraction of a second for it vaporize wort into smoke. My HERMS system with a false bottom will pump the false bottom dry at about 30% throttle depending on the grist makeup.

If you have sight gauge that reads 15 gallons with the pump off and then reads 10 gallons with the pump on you have a vacuum and it's only a matter of time before the element get exposed.

 

[BrunDog]

I think both @wilserbrewer and @LarMoeCur touched on very important points. One, the FB will hinder effective circulation during the boil. Second, recirculating with a pump while boiling is uncommon. But that coupled with the FB will cause a problem - when the pressure is reduced around the element, boiling will happen at a elevated rate. But when the liquid flashes off the element, the volume expansion relieves some of the vacuum. This will cause a pressure oscillation and may cause super heated regions on the element. Therefore, it may be prudent to eliminate the FB altogether or at least before the boil. Also your boil should be a nice simmer, not a raging rapid.

 

[lalh20]

My fb isnt like some it has about an inch around it on all sides (and about 15 holes in it larger than the port the pump pulls from). I dont feel like it could impede flow anywhere near fast enough to cause a measurable pressure gradient during the boil.

That said, ill make it a habit to remove it if I dont need ot to keep the hop bag off the element.

Do you not have issues woth the bag touching the element?

 

[augiedoggy]

I have seen many scorch threads and just about every one has one of two things in common... either they turned the element off long enough (or the flow over the element was so slow) that proteins settled on top of the element or they are direct firing the mash in some way...

are you sure no air is getting trapped under the fb/bag? How are you measuring the flow of your recirculation? even if you dont do it for long once the proteins settle and start scorching it will just keep going even after you have increased the flow to the element area.

 

[augiedoggy]

Or just replace the element.... they are cheap enough!

Versus cleaning them?
Depends on the style of element and who your buying them from... More people are using the TC based ones these days and those range quite a bit in price.

 

[BrunDog]

Not sure replacement is OT but true that $ is varied. I think at the end of the day spending the money is better than burnt beer though!

 

[LarMoeCur]

I think both @wilserbrewer and @LarMoeCur touched on very important points. One, the FB will hinder effective circulation during the boil. Second, recirculating with a pump while boiling is uncommon. But that coupled with the FB will cause a problem - when the pressure is reduced around the element, boiling will happen at a elevated rate. But when the liquid flashes off the element, the volume expansion relieves some of the vacuum. This will cause a pressure oscillation and may cause super heated regions on the element. Therefore, it may be prudent to eliminate the FB altogether or at least before the boil. Also your boil should be a nice simmer, not a raging rapid.

I don't think the OP is recirculating during the boil. He is recirculating the mash and heating under a false bottom.

I'm not sold removing the false bottom will help the problem. The grain bag is very heavy and will lay directly on the element. Scorching for sure. I think you need a way to support the grain bag and be open enough for the wort to flow unrestricted. I've seen pictures of wire frame type supports that allow unrestricted flow. That's would be the fix in my mind.

It's one of two things. Proteins settling on the element or a vacuum created by the pump. I believe fixing the grain bag support structure will fix both problems. Allowing the pump to be run at 100% with out a vacuum will keep the proteins in solution.

 

[augiedoggy]

I don't think the OP is recirculating during the boil. He is recirculating the mash and heating under a false bottom.

I'm not sold removing the false bottom will help the problem. The grain bag is very heavy and will lay directly on the element. Scorching for sure. I think you need a way to support the grain bag and be open enough for the wort to flow unrestricted. I've seen pictures of wire frame type supports that allow unrestricted flow. That's would be the fix in my mind.

It's one of two things. Proteins settling on the element or a vacuum created by the pump. I believe fixing the grain bag support structure will fix both problems. Allowing the pump to be run at 100% with out a vacuum will keep the proteins in solution.

I agree this was an issue for some of the early adopters of the brew boss systems when they had the straight LWD elements... There just isnt enough flow under the fb just about every time I see ULWD and scorch in the same statement I look for this type of setup being implemented..

 

[andrewmaixner]

I agree this was an issue for some of the early adopters of the brew boss systems when they had the straight LWD elements... There just isnt enough flow under the fb just about every time I see ULWD and scorch in the same statement I look for this type of setup being implemented..

And maybe we need a new acronym for the ripple ULWD, versus straight ULWD.

The Ripple shall henceforth be called a Hyper Low Wall Density element: HLWD :rockin:

 

[augiedoggy]

And maybe we need a new acronym for the ripple ULWD, versus straight ULWD.

The Ripple shall henceforth be called a Hyper Low Wall Density element: HLWD :rockin:

to be honest most (not all) of the straight elements are really LWD. all the 240v straight ones that fit in a home brewing kettle are at least.
My 36" long straight rims element is even lower watt density than the ripples so..