First brew on the new BZ4

[Leard]

This is my first brew in several months now, and the first with my new BrewZilla Gen 4. I brewed an altbier that I had bought the ingredients for back at the start of the year. I have to say, this was a very weird brewday, based upon all the numbers that I obtained. I've done many brews before, so it's not like I don't know how to use a hydrometer etc.

I did a 60 minute mash at 66.7. A 30 minute boil. I tried out the pizza tray sparge method, where I ran my sparge water from the peco onto a tinfoiled pizza tray that was sat on top.

I use Beersmith, and I relied upon the add-on already created for the 35L BrewZilla Gen 4.

Here's where the volumes and figures get weird. Or weird in the sense that Beersmith seems to have completely miscalculated everything.
For a 20L batch, I mashed with 14L of water, and sparged with 15L. Beersmith estimated my pre-boil volume would be 24L. However, I somehow ended up with 27L. It estimated my post-mash gravity as 1.040. Well somehow, I ended up with 1.062. Apparently that gave me a mash efficiency of 132.5%. Wtf? It then estimated my pre-boil gravity as 1.040, but I ended up 1.059.

Post boil, I ended up with 24L of wort and an OG of 1.040, when Beersmith estimated an OG of 1.046.

So I have absolutely no idea what happened here. Perhaps there's something wrong with the pre-created Beersmith profile for the BZ4? Although that doesn't explain the weird gravity readings I was getting. My hydrometer is definitely working fine. I've never had issues measuring gravity before, and I've never seen such readings all over the place. It's crazy that I managed to achieve higher than estimated post-mash and pre-boil readings, and yet still miss the OG. Any thoughts what caused this?

Except for the weird readings, I think it all went well. The BZ4 is amazing. It's very easy to use. I had a bit of trouble with the profile I set up. I ended up just manually controlling it post-mash because it seemed to skip right over my mash out stage.

 

[Rwilts]

Think your probably right about the profile. You will need to create your own based on how it behaves .if we presume a 5kg grain bill you could have lost 5L of water after mash = 9 + 15 sparge = 24 which sounds what was predicted. I suspect deadspace being an issue

Also are you happy with your water quality measurements ?

Does the profile account for the short boil time ?

 

[Agentgonzo]

Post mash and pre boil gravity. I assume you took a sample from the bottom of the wort? The first runnings will contain the majority of the sugars and be a much higher density. The sparge will be a lower gravity and sit on top of the first runnings unless you mix it really well (a simple stir won't do this). So taking a reading from the bottom will be incorrectly high, and taking a reading from the top will be incorrectly low

The boil will give it a really good mix though. An OG of 1.040 when beer smith expected 1.046 isn't too bad. It just means your efficiency is slightly lower than what beer smith used. Adjust it for the next brew, and after the next couple of brews and you'll be hitting your expected numbers in no time.

 

[foxy]

You didn't mention the weight of the grain bill but I would be thinking around 4.5 to 5 kg. Minimum loss to grain, if you give the bed a good squeeze 3.8 -4.2 litres using 29 litres, should become around 25 litres going into the boil. I don't know the dia of the kettle but should probably lose around 2-2.5 litres in the boil.
Some of those SVB's markings don't include the dead space, Guten doesn't, not sure about Brewzilla G4
So as said above, don't go by the predicted profiles you have to make your own. Giving the wort a good stir and pouring it into a jug and then into the hydrometer tube will give you a closer pre-boil gravity.

 

[Ben034]

I've had a similar experience a few weeks ago. Also using Beersmith as a starting profile for a new BZ4. I've brewed for many years but used BIAB until now.

My pre boil volume was significantly higher than expected, with the boil off lower (because i set the boil power lower than full - couldn't see the need for such an aggressively vigorous boil).

End result was a much lower OG. I also had really bad efficiency from the mash which I suspect was my fault for not paying attention and not stirring during the mash (as well as a much higher boil volume) and possibly optimistic starting efficiency (maybe not when I've learnt the system fully).

I've tweaked the profile on Beersmith for the next time. In Beersmith I've said there's no dead space which would have given me the correct pre boil volume at least. I've tweaked the grain absorption rate in Beersmith advanced settings and lowered my predicted brewhouse efficiency.

I think others could be right with the reasoning for strange gravity readings. I've definitely done similar before.

I also found every other aspect of the first use of the BZ really easy apart from the off numbers. I went with a forgiving bitter recipe where it would be ok with a low or higher than expected OG. I actually added some sugar as didn't have any malt extract to hand to make up for it. I actually think having some malt extract to hand for the first few brews on a new system is really useful as you can easily adjust for any inefficiency and takes some of the stress out of learning the new system.

 

[Twostage]

I've had a similar experience a few weeks ago. Also using Beersmith as a starting profile for a new BZ4. I've brewed for many years but used BIAB until now.

My pre boil volume was significantly higher than expected, with the boil off lower (because i set the boil power lower than full - couldn't see the need for such an aggressively vigorous boil).

End result was a much lower OG. I also had really bad efficiency from the mash which I suspect was my fault for not paying attention and not stirring during the mash (as well as a much higher boil volume) and possibly optimistic starting efficiency (maybe not when I've learnt the system fully).

I've tweaked the profile on Beersmith for the next time. In Beersmith I've said there's no dead space which would have given me the correct pre boil volume at least. I've tweaked the grain absorption rate in Beersmith advanced settings and lowered my predicted brewhouse efficiency.

I think others could be right with the reasoning for strange gravity readings. I've definitely done similar before.

I also found every other aspect of the first use of the BZ really easy apart from the off numbers. I went with a forgiving bitter recipe where it would be ok with a low or higher than expected OG. I actually added some sugar as didn't have any malt extract to hand to make up for it. I actually think having some malt extract to hand for the first few brews on a new system is really useful as you can easily adjust for any inefficiency and takes some of the stress out of learning the new system.

This is good info here, looking forward to Santa bringing mine.

re: the off numbers. In some ways its funny that we chase the numbers so much. With my last brew I'd thought the OG was less than it actually was and I was disappointed the ABV was 4.0%. When I rechecked the OG the ABV was actually 4.3% and I was a lot happier even though I'm not sure I could detect 1.5ml of alcohol in a pint . I'm sure there's someone on here who doesn't take gravity readings at all.

 

[Ben034]

Yeah for most styles it's probably not hugely important. There's definitely some satisfaction when you do hit the numbers though! I think I like to be close so I can repeat if needed next time. I definitely like making the same thing multiple times, tweaking little things.

 

[Leard]

II've tweaked the profile on Beersmith for the next time. In Beersmith I've said there's no dead space which would have given me the correct pre boil volume at least. I've tweaked the grain absorption rate in Beersmith advanced settings and lowered my predicted brewhouse efficiency.

So there's the recoverable deadspace, and deadspace losses. I've got the recoverable deadspace as 2.5, as this is the space underneath the grain basket that gets recirculated. However I don't think there are any deadspace losses with the BZ4. Have you set your recoverable deadspace as 0? If I change the recoverable deadspace to 0, it doesn't actually affect the total water used, it just moves it from the mash to the sparge.

I suppose when I sparge next time I could just keep going until I actually reach the pre-boil volume and not use the entire amount water Beersmith suggests.