Verdant IPA

[Alex Helbig]

Hi all. I’m trying to brew one of David Heath’s recipes forverdant IPA.


My first attempt at this recipe I aimed for a 10 L batch and significantly missed my gravity targets. Today I’m trying again - this time with a full-size batch. Once again I am well under gravity for this recipe.

The grain bill I’m using for this recipe is:
3.042kg Ale Malt
0.862kg Vienna malt
0.254kg Carahell
0.152kg Carapils
0.761kg Flaked oats (Uncle Toby’s Quick Oats)

My brewing system is a Brewzilla 65 L GEN 4. I have added the grist to 20 L of mash water at 65°C. Mashed for an 40 minutes at 65°, followed by 20 minutes at 68°, with an 10 minute mash out at 76°C. After mashing, I am sitting at about 1.053 SG.

Then used a rinse Sparge with sufficient water to bring the volume up to 26L. My pre-boil target is 1.050SG, but the measured value is only: 1.044.

Did a 30 minute boil. Volume reduced to 24L post boil and the measured gravity was 1.042. My target, however was 1.053.

Using Brewfather as the software solution for this brew.

So in short, it seems that I’m miles out from where I need to be. I have had reasonable success with this system until this brew. This is my first recipe using oats,I’m wondering whether the quick oats have not contributed to the sugars in the wort. If I remove the flaked oats from the recipe in Brewfather, then I end up about the gravity that I measured. It’s as if the oats weren’t there.

Would love some suggestions on how to improve my success.

Cheers,
Alex

 

[philrob]

Did you allow adjustment for the temperature of your wort in your readings?

 

[Tangle Foot]

Did you allow adjustment for the temperature of your wort in your readings?

Yes. Used a calculator to adjust for temperature. Most readings were taken two or three times to confirm.

Brewhouse efficiency is set at 75%. Although I’m not sure how dialled in that is yet, as I have only done 6 or 8 brews with the Brewzilla. Before that I have about 120 BIAB brews done in a 40 L Crown urn. Most of the brews I’ve done with the new system have been in the ballpark (3-5 gravity points above or below). But these last two , I’m so far out, I’m tempted to go back to my urn.

 

[Tangle Foot]

Yes. Used a calculator to adjust for temperature. Most readings were taken two or three times to confirm.

Brewhouse efficiency is set at 75%. Although I’m not sure how dialled in that is yet, as I have only done 6 or 8 brews with the Brewzilla. Before that I have about 120 BIAB brews done in a 40 L Crown urn. Most of the brews I’ve done with the new system have been in the ballpark (3-5 gravity points above or below). But these last two , I’m so far out, I’m tempted to go back to my urn.

Sorry for the change of account - I somehow ended up with two logins to AHB.

 

[Half Pint]

For one thing there’sa problem with your measurements as you’ve boiled off 2 litres and then measured a lower SG than you had pre boil.
I’ve heard of people having lower than expected mash efficiency from Gen4 Brewzilla. In those cases it seems like the problem was about the mash temperature ie the actual temperature of the mash was lower than indicated on the display. This was early days for the gen 4 and apparently something to do with the wort effectively channeling down the middle and not mixing very well. I have the impression that’s been sorted now so probably you’re all over that, but a colder than expected mash could explain your low numbers and poor mixing could explain the anomaly in pre boil and post boil SG readings

 

[Tangle Foot]

I do wonder about the mixing. Once you put the top plate in the malt pipe you can’t easily stir the mash. The recirculation pump is going the whole time, but there could be channeling. Back in my BIAB days I had no recirculation so I tended to give the mash a good stir every 10-15 minutes.

I’ve noticed a lot of variability between successive gravity measurements. So have typically taken the average of two or three measurements.

Also just remeasured the post boil gravity this morning. I’ve got 1.047SG. The hydrometer temperature adjustment calculator. I use is in the Brewer’s Friend app and I have noticed that I don’t think it’s very accurate at the higher temperature ranges. So I always leave my final sample to cool overnight and then I can take a room temperature gravity reading to accurately determine my OG for fermenting.

 

[Half Pint]

I do wonder about the mixing. Once you put the top plate in the malt pipe you can’t easily stir the mash. The recirculation pump is going the whole time, but there could be channeling. Back in my BIAB days I had no recirculation so I tended to give the mash a good stir every 10-15 minutes.

I’ve noticed a lot of variability between successive gravity measurements. So have typically taken the average of two or three measurements.

Also just remeasured the post boil gravity this morning. I’ve got 1.047SG. The hydrometer temperature adjustment calculator. I use is in the Brewer’s Friend app and I have noticed that I don’t think it’s very accurate at the higher temperature ranges. So I always leave my final sample to cool overnight and then I can take a room temperature gravity reading to accurately determine my OG for fermenting.

I have also noticed that BF temperature correction calculator doesn’t quite match up with my hydrometer at higher temps. I expect it’s calibrated for a quality instrument and my hydrometer is about the cheapest.

Do you have a separate thermometer for your mash or just the built-in temperature sensor?

 

[wide eyed and legless]

I think your post mash reading of 1,053 was out . Easily happens with readings post mash as the sugars are not evenly spread throughout the wort.
The ratio of a mash tun is 1-1.6 so they are shorter than they are wide, obviously on a homebrew scale that ratio wouldn't be acceptable because of storage space but I would like to see a greater diameter on a homebrew scale.
The Brewzilla is the narrowest diameter kettle so that is never going to help with efficiency, neither will having the top plate in situ.
Depending on my grain bill I will stir for 15 to 20 minutes keeping the tap fully open. You will feel the viscosity lowering as the starch converts to sugar then leave alone and let it settle.
Compaction of the grain at the bottom of the mash tun doesn't help the enzymes convert the starches, also don't take too much notice of David Heath and his 30 minute boils, it wasn't that long ago he was asking how to use the canned kits on the English forum.

 

[Tangle Foot]

.
Do you have a separate thermometer for your mash or just the built-in temperature sensor?

I have the Bluetooth thermometer so that I can measure temperature at the top of the malt pipe as well as the built-in.

 

[Tangle Foot]

don't take too much notice of David Heath and his 30 minute boils,

I normally do 60 minute boils. This is only the second time I’ve tried a 30 minute boil. Was wanting to see if I noticed a difference in the outcome.

 

[Dave70]

I took up 30 minute boils on the strength of David's vids, and things began to go wonky.
Switched back to 60 and consistency more or less returned. Dunno why.
Granted, I don't have a nervous breakdown over a couple of points here and there. I think the fermentation stage is where you need to be on point.

As WEAL said, put some elbow grease into the mash and keep the juices flowing.

There's also something to be said for leaning your system.
You need to be consistent before you can be precise, at least in my experience.

 

[clickeral]

Not sure if this will help as youve had success with previous brews but



Is what I use on mine, whats your crush like?

I don't use the top plate and I stir throughout the mash (roughly every 30mins or 15mins if shorter mashes) I found flow rate on the pump needs to not be full bore as well especially using the top plate as it really condenses the grain bed more then you want

Grain absorption is 1L/kg and I mash with circa 3.2L/kg

This is the standard brewfather profile I tweaked for 23L and no chill (I use 2x11L cubes for single batches)

If you were local id happily do a brew with you to see if it helps

Note I also have a big 3v that I switch to for doubles, triples, quad batches etc (150L ready to ferment volume is my max)

Oats can be tricky to mash, I try to add mine throughout mash in so they dont stick/clump together