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Help - First Full Grain BIAB and I have low OG

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PhilBrew

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5.5 US Gallons, so about 21L.
1) I started with 23L in the Peco boiler for a 60 minute mash. That was a pure guess.
2) I then topped it up once I took the grain out and set the Peco to boil for 60 mins. Boiling in a Peco is done with a loose lid. As opposed to a converted cooler or an enclosed system, this does increase the boil off.
3) Before I screwed it up by adding more water to the FV, I had about 18.8L in the FV
... OK, so it looks like the recipe assumed a Brewhouse Efficiency (BE) of 75% ... and depending on whether you measured that gravity of 1.032 at 18.8 lts or after topping up (to 21 lts? and after giving the wort a thoroughly good mixing with that water?) it looks like you've achieved a BE of around 50-55% ... Ouch! :eek: ... of course, if you measured that gravity after topping up, but you didn't mix that water in thoroughly, then this may be a case of the issue some kit brewers have with measuring a gravity where all the sugars were sitting in the more dense wort at the bottom of the FV :?:

If you're sure you mixed thoroughly ... follow what Terry said wink...

Cheers, PhilB
 

HeavensBrew

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To get a pre boil volume of 28L I started with 33L which was split between 20L mash and 13L sparge. Grain bill for my recipe was 6kg so a lot of grain absorption.

28L into the boil left me with 23L after 90 mins and I kept the boiler on throughout. I used the puffer jacket to maintain temp for the mash at 65 degrees.

My dunk sparge was literally sitting the bag in a spare FV for 15 mins and then pulling it out and lightly squeezing it using an oven rack (tip picked up from the forums - thank you!) to take the weight of the bag.

Hope that helps - sorry if my post confused !
Based on your figures, I should plan on 25l of water. That makes sense based on what occurred on the day. Next time I will mash at 17l and sparge with 8l.

How did you heat your sparge water? I'm guessing you heated the water in in your Peco while the bag was in the spare FV, but it's the technique for the next part that interests me. Did you then dunk the bag straight into the Peco filled with hot water? Or did you pour the hot water over the bag in the spare FV and then move the bag back to the peco and pour the water over again?

As for the dunk sparge, I had put the bag into a clean bucket and then poured the liquid collected back into the peco. I had only planned to used the bucket as somewhere to stick a wet bag full of grain.
 

ChrisT685

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Based on your figures, I should plan on 25l of water. That makes sense based on what occurred on the day. Next time I will mash at 17l and sparge with 8l.

How did you heat your sparge water? I'm guessing you heated the water in in your Peco while the bag was in the spare FV, but it's the technique for the next part that interests me. Did you then dunk the bag straight into the Peco filled with hot water? Or did you pour the hot water over the bag in the spare FV and then move the bag back to the peco and pour the water over again?

As for the dunk sparge, I had put the bag into a clean bucket and then poured the liquid collected back into the peco. I had only planned to used the bucket as somewhere to stick a wet bag full of grain.
I mash and boil in the Peco so I heated my sparge water on the stove and then poured into the FV over the grain then just left it to sit. I then lightly squeezed and then poured the sparge water into the reminder of the wort in the boiler.
 

HeavensBrew

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... OK, so it looks like the recipe assumed a Brewhouse Efficiency (BE) of 75% ... and depending on whether you measured that gravity of 1.032 at 18.8 lts or after topping up (to 21 lts? and after giving the wort a thoroughly good mixing with that water?) it looks like you've achieved a BE of around 50-55% ... Ouch! :eek: ... of course, if you measured that gravity after topping up, but you didn't mix that water in thoroughly, then this may be a case of the issue some kit brewers have with measuring a gravity where all the sugars were sitting in the more dense wort at the bottom of the FV :?:

If you're sure you mixed thoroughly ... follow what Terry said wink...

Cheers, PhilB
1032 at 18.8L. It was a well mixed batch at that point. I have learned a lot from the experience though.
I mash and boil in the Peco so I heated my sparge water on the stove and then poured into the FV over the grain then just left it to sit. I then lightly squeezed and then poured the sparge water into the reminder of the wort in the boiler.
Thanks!
 

AdeDunn

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I keep saying this to folks just starting out with BIAB, AG kits are a massive mistake, simply because of the assumed brewhouse efficiency when the grain is weighed out.

Starting out, I found some recipes (books and the like) and put them into software, then adjusted them using the software (started with BIABacus, switched to Beersmith which I still use to this day) to a lower brew house efficiency. Then ordered accordingly. Most suppliers offer custom kits so will still weigh everything out for you if you don't want that bother. Cheaper though to buy more than you need and use the grain for other brews (pale malt you will find used in many many different beers for example), then you can just buy hops you need, and have fun weighing it yourself.

I still do this now, only I buy in bulk. I'm getting used to new equipment, so have my brewhouse efficiency set to 60% whilst I get my process honed once more. When I did normal BIAB though, I stirred every 20 minutes, and was VERY thorough doughing in, I found that slow and steady won the race doughing in, and remember you don't stir the malt, you want to lift it too as you stir, so it gets into the water column to rinse all those sugars. I sometimes dunk sparged too, but would treat it like a tea bag, lifting and dunking repeatedly to give it a good rinsing with the sparge liquid. Always remember, sparging is rinsing, you're rinsing sugars off the grain. athumb..

Lastly, probably an idea to keep a kilo or so of DME in your brewing store cupboard, you never know when it might come in handy. Especially if you start using liquid yeasts and need to to make starters up.... I really hope this helps a little.
 

Darren1973

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Im only a noob but I wouldn't worry too much, my last 2 brews were 0.1 below the OG on the recipe but the ABV was still 4.4ish in the end, you may find your SG will be lower too :)
 

AdeDunn

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Im only a noob but I wouldn't worry too much, my last 2 brews were 0.1 below the OG on the recipe but the ABV was still 4.4ish in the end, you may find your SG will be lower too :)
Guessing you mean FG? As OG is usually measured in SG (specific gravity) too. But yes, it will be lower, as attenuation for the yeast will more or less be the same, so start higher, finish higher, start lower, finish lower, it won't increase the ABV though unless you also increase apparent attenuation of the yeast (adding sugar to "dry out" the beer, or using a yeast like a French Saison yeast with higher apparent attenuation.). That's a 2 edged sword though, as it can leave the mouth feel really watery. French Saison yeast is different, it modifies mouth feel even whilst producing "drier" beer. So like my IPA started at 1.064 and dropped to 1.010, my APA started at 1.044 and finished at 1.008 because it started lower, the IPA actually had slightly higher attenuation even though I used the same type of yeast, just because.... It didn't increase the alcohol in the APA though finishing lower, it just did what was expected for that yeast.

I know somebody else could probably explain it better, but hopefully that helps a bit.

Just to note, and kinda proof of concept so to speak regarding not using ready made kits. My last brew day, I used my own recipe, set to 60% estimated brewhouse efficiency with a target OG of 1.045 with 14 litres into FV. I only got about 13 litres into FV, with an OG of 1.044, my software says this is a BG efficiency of of 54.2%, a figure you probably see as close to your own. Beer as you see above has finished at 1.008, giving me an ABV of 4.7%, and is delicious, rather than the target 5.1% ABV. It's a much smaller miss, if that makes sense? I had tons go wrong during the brew day, my pump clogged half way through and had to be stripped down for one, pipes kept clogging with grain that should have stayed in the malt pipe but the crush is too fine, and I rushed things, 2nd time using my new equipment. It's probably the tastiest beer I ever brewed going by the sample I drew the other day for the FG sample.... lol
 
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HeavensBrew

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I keep saying this to folks just starting out with BIAB, AG kits are a massive mistake, simply because of the assumed brewhouse efficiency when the grain is weighed out.

Starting out, I found some recipes (books and the like) and put them into software, then adjusted them using the software (started with BIABacus, switched to Beersmith which I still use to this day) to a lower brew house efficiency. Then ordered accordingly. Most suppliers offer custom kits so will still weigh everything out for you if you don't want that bother. Cheaper though to buy more than you need and use the grain for other brews (pale malt you will find used in many many different beers for example), then you can just buy hops you need, and have fun weighing it yourself.

I still do this now, only I buy in bulk. I'm getting used to new equipment, so have my brewhouse efficiency set to 60% whilst I get my process honed once more. When I did normal BIAB though, I stirred every 20 minutes, and was VERY thorough doughing in, I found that slow and steady won the race doughing in, and remember you don't stir the malt, you want to lift it too as you stir, so it gets into the water column to rinse all those sugars. I sometimes dunk sparged too, but would treat it like a tea bag, lifting and dunking repeatedly to give it a good rinsing with the sparge liquid. Always remember, sparging is rinsing, you're rinsing sugars off the grain. athumb..

Lastly, probably an idea to keep a kilo or so of DME in your brewing store cupboard, you never know when it might come in handy. Especially if you start using liquid yeasts and need to to make starters up.... I really hope this helps a little.
Thanks for your feedback.

I had not used a kit. The last kits I used were 3 x part-grain kits from Dark Rock which were spectacular and it was those that had encouraged me to go all-grain. I had considered kits, software and lot’s of shiny-technology, but decided that I need to learn the basics. So I picked some recipes and ordered some materials (+50kg) and decided to get going. (I also ordered a specialist food storage bin for the grain. Hops are in the fridge and then freezer once the seal is broken).

As can be seen on this thread, I have lot’s of improvements to make. However, this way I understand the ‘why’. Mistakes can also be considered necessary steps, as long as you don’t repeat them frequently. Reminds me of the saying ‘Good sailors are not made in calm seas’.

Lifting the malt as I stir is certainly a handy tip that I had not heard before.

DME – I have 500g for this brew arriving on Monday together with a refractometer. I then have another kg of DME arriving with some more hops in about a week. As soon as this batch is kegged’n’bottled I will be brewing the next batch!

I do fancy checking out the software though, mainly so I have more flexibly in batch sizes. Does the software predict IBU/bitterness? I’d like to say I brew for myself, but I like my friends to enjoy it too and they are mostly deterred by the bitter recipes.
 

HeavensBrew

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Im only a noob but I wouldn't worry too much, my last 2 brews were 0.1 below the OG on the recipe but the ABV was still 4.4ish in the end, you may find your SG will be lower too :)
I’m going to add 500g of DME on Monday (with the rest of the yeast) just to be on the safe side. More importantly, I will become a ‘sparging-maniac’ for the next brew!
 

AdeDunn

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Thanks for your feedback.

I had not used a kit. The last kits I used were 3 x part-grain kits from Dark Rock which were spectacular and it was those that had encouraged me to go all-grain. I had considered kits, software and lot’s of shiny-technology, but decided that I need to learn the basics. So I picked some recipes and ordered some materials (+50kg) and decided to get going. (I also ordered a specialist food storage bin for the grain. Hops are in the fridge and then freezer once the seal is broken).

As can be seen on this thread, I have lot’s of improvements to make. However, this way I understand the ‘why’. Mistakes can also be considered necessary steps, as long as you don’t repeat them frequently. Reminds me of the saying ‘Good sailors are not made in calm seas’.

Lifting the malt as I stir is certainly a handy tip that I had not heard before.

DME – I have 500g for this brew arriving on Monday together with a refractometer. I then have another kg of DME arriving with some more hops in about a week. As soon as this batch is kegged’n’bottled I will be brewing the next batch!

I do fancy checking out the software though, mainly so I have more flexibly in batch sizes. Does the software predict IBU/bitterness? I’d like to say I brew for myself, but I like my friends to enjoy it too and they are mostly deterred by the bitter recipes.
IBUs, OG, FG, ABV.... Pretty much everything you need it to do really, I use Beersmith 3. There's a free trial available for it if you wanted to give it a go. There's also the forum sponsor software, and I used to use a spreadsheet called BIABacus but honestly that's a pain in the backside to use. lol Oh, and folks have mentioned Brewfather online app a few times too. I like Beersmith 3 though as I have both the desktop version, and the Android app for it on my phone, and the subscription I have allows me to upload my recipes to a private area on their server, then access them from my phone. What I don't like is that the mash acid tool built into it can't use CRS, only Lactic acid, Phosphoric acid or acid malt, but no biggy I used a water additions calc from off here. That's probably a bit beyond where you are right now anyway. Crush size, doughing in and stirring will get you the biggest gains I reckon. Get them down, and you'll be well away. Oh, and once you are using software, you can reduce efficiency for the recipe, allowing you to add more malt in order to offset lower efficiency.

Maybe try a SMASH? Nice easy way to get things down, 1 malt, 1 hop. Pick a hop you know you like from beers you have had in the past.
 

HeavensBrew

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IBUs, OG, FG, ABV.... Pretty much everything you need it to do really, I use Beersmith 3. There's a free trial available for it if you wanted to give it a go. There's also the forum sponsor software, and I used to use a spreadsheet called BIABacus but honestly that's a pain in the backside to use. lol Oh, and folks have mentioned Brewfather online app a few times too. I like Beersmith 3 though as I have both the desktop version, and the Android app for it on my phone, and the subscription I have allows me to upload my recipes to a private area on their server, then access them from my phone. What I don't like is that the mash acid tool built into it can't use CRS, only Lactic acid, Phosphoric acid or acid malt, but no biggy I used a water additions calc from off here. That's probably a bit beyond where you are right now anyway. Crush size, doughing in and stirring will get you the biggest gains I reckon. Get them down, and you'll be well away. Oh, and once you are using software, you can reduce efficiency for the recipe, allowing you to add more malt in order to offset lower efficiency.

Maybe try a SMASH? Nice easy way to get things down, 1 malt, 1 hop. Pick a hop you know you like from beers you have had in the past.
Here's a test for you and your software if you have the time. My next brew on the list is called: Golden Plains Cream Ale: OG 1.051 FG 1.013 ABV 4.98% and it's a 21L Batch.

The grain bill calls for 2kg of Pale Malt
2kg of German Pilsner (I will use Belgian as I have Belgian in the house) and.....drum roll....680kg of flaked corn. From investigation, I understand that I can swap flaked corn with cornflakes of an equal weight (yes, breakfast cereal).

Considering a 60% typical BIAB efficiency, what grain bill should I adjust too? Is the maths to multiply by 75/60? In which case 2kg becomes 2.5kg?

Bonus Question: Does BeerSmith account for such ingredients as cornflakes?
 

AdeDunn

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Here's a test for you and your software if you have the time. My next brew on the list is called: Golden Plains Cream Ale: OG 1.051 FG 1.013 ABV 4.98% and it's a 21L Batch.

The grain bill calls for 2kg of Pale Malt
2kg of German Pilsner (I will use Belgian as I have Belgian in the house) and.....drum roll....680kg of flaked corn. From investigation, I understand that I can swap flaked corn with cornflakes of an equal weight (yes, breakfast cereal).

Considering a 60% typical BIAB efficiency, what grain bill should I adjust too? Is the maths to multiply by 75/60? In which case 2kg becomes 2.5kg?

Bonus Question: Does BeerSmith account for such ingredients as cornflakes?
Pretty much yeah, Beersmith 3 is telling me:-

2.5k of pale malt
2.5k of German pilsner malt
0.85k of flaked corn (fairly certain you meant 680g not kg, or you are opening a huge brewery... lol).

Remember though, the amount of water you use changes a little when you increase the quantity of grain, to account of that absorbed by the grain that you can't retrieve. More grain=more water lost to the grain. That's where you use an equipment profile though, setting things like boil off rate, loss to trub etc, so the software can calculate the total amount of water you need as accurately as possible. Even BIABacus does this, as does all software. The whole "you need this much water" in recipes, well sure, if you live with them and are using their equipment. ;)

As to whether flaked corn and cornflakes are the same thing, I refer you to this thread Using Flaked Maize (aka The Great Cornflake Debate). You can add any ingredient you like pretty much to Beersmith, in the case of fermentables you'd just need to know a few things like extract potential, yield, coarse fine difference, moisture and protein (you'd set diastatic power to 0 lintner as they have none). Or you just use flaked corn in beersmith 3 and assume it's close enough.

I've added my plate chiller as a misc item for example, just to remind me to start running boiling wort through it 15 minutes before flame out.

Hopefully be doing a brew myself on Wednesday too. athumb..
 

HeavensBrew

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Thanks! Just checking my maths will be a big help (especially when I start making smaller batches of stout - which less people like).

It's going to be cornflakes. Not in Blighty at the moment and some ingredients are harder to get cost effectively here. Funny as I also started the debate on this forum about oats being used to clarify a brew.....and it turned out to be true.

I'm very keen to start my next brew, so the sooner the current one ferments the better. That will be delayed by adding the DME and more yeast yesterday.

What are you brewing?
 

AdeDunn

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No probs, happy to help. I tend to make porters rather than stout, less roasty. I still get people turning their noses up at it, but that's ok as it's for me anyway.... :laugh8:

I've not used flaked corn yet to be honest, kind of been avoiding it... Used oats in small quantities though. I avoid large quantities as oxygenation is a bigger issue with larger quantities of oats, and I don't have a closed system when it comes to bottling etc (which is why I steer clear of brewing NEIPAs).

Brewing an orange infused pale ale. Somebody asked for the recipe so I put it on my brewday thread, along with details of the prep I've been doing. I do small batch volumes too, I aim for 14 litres. So far had an 8 and a 10 as still getting used to new equipment, so things go wrong. It's just the way of it, so long as the beer comes out tasting ok I just roll with it. athumb..
 
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