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Petegriffin

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Hi all,
Recently got into brewing and am really enjoying it. However I'm keen to get my quality and consistency up to better justify the days spent in the garage.

My first big concern (of quite a few) I'd like to sort is my terrible mash efficiency. Any pointers would be much appreciated.

I'm using a pretty basic set up but I'd hoped I'd be able to get good results anyway. It's a Peco boiler with a grain bag from thehomebrewcompany.co.uk

I got a grain kit from the same firm and it came crushed, does anyone have any experience of them and if that's crushed enough to use in BIAB? This brewday was for a stout recipe (2.5kg pale, 0.5kg oats, 0.5kg wheat, 0.25kg choc, 0.25kg roasted barley, 0.25 Munich) and I started with 26L of water.

I'm getting the water up to about mash temp and then adding the grain. Yesterday I wanted to mash at 63.5C so I got the water to 65 and added the grain, doing so in three goes with a big stir between each. I mashed for 80 mins and stirred quite aggressively every 15 minutes.

I tried to squeeze the bag quite a bit afterwards but have heard mixed messages about this. After I left the bag in a tub to drain I did see it had quite a bit left absorbed so I wonder if it's worth going the extra mile on the squeeze or maybe even dunk sparging and allowing for a bit longer on the boil to compensate?

I took a sample pre-boil and measured a SG of 1.034 which looks like an efficiency of just under 55%.

At the end of the day I got about 4 gallons off into fermenters with an OG of 1.044 so I'm happy I'll get something drinkable (the last batch was tasty but a little watery) but I was hoping for a much bigger beer than this.

Any help, critiques, tips or mockery are very welcome.
 
63.5C sounds pretty low? I normally mash around 67c for a medium body, which when I did BIAB meant heating the water to about 70c then adding the room-temperature grain which resulted in about 67c.

Are you insulating the boiler during the mash? I'd perhaps stir only once or twice during the mash to avoid losing heat and wrap it all up with a blanket to keep the heat in.

Given the ingredients (assuming a 20l batch) 1.044 doesn't sound way off to me - how are you calculating the efficiency? I just put the ingredients into beersmith using my equipment profile and it says 1.047, so maybe you just need to add more base malt?
 
Temps too low at 63c for a full bodied beer like a stout i think, the other thing is that are you sure that when you put the bag in at 65c the temp only drops to 63? Mine drops a lot more than that, I usually heat my water to about 73c and then put the bag in. However as Steve said 1044 doesn't sound too bad to me.
 
Thanks for the ideas.

I'll up my temperature next batch and see how it goes, I was using this based on some reading around on the beersmith site.

I've been using the boiler heating element to maintain the temperature during the mash. Is that likely to be an issue?

Regarding the measurements I'm using beersmith too. I was focussing on the post mash numbers and it suggested 1.034 gave 54.7% efficiency. My boiler struggles to keep a rolling boil so I ended up with a little over 20L (beersmith was aiming for 18L into the fermenter) so I know I have some improvement to count on there with a longer boil, so I was wanting to work on the mash stage for now.
 
Temps too low at 63c for a full bodied beer like a stout i think, the other thing is that are you sure that when you put the bag in at 65c the temp only drops to 63? Mine drops a lot more than that, I usually heat my water to about 73c and then put the bag in. However as Steve said 1044 doesn't sound too bad to me.
A... about face. 63C (even 62C) is more for lighter bodied very fermentable worts. 69-70C is for full bodied well flavoured beers. Lower temperatures are common with the current trends in beer; even the common "average" of 66-67C would have been considered cool 100-150 years ago.

(EDIT: Rereading @pilgrimhudd's post - he probably didn't mean my "a... about face" translation as that could just be reading his words with a different emphasis. I can do that with my scribbling. It's a problem with trying to be conversational with the written word. I guess that's where all this emoji nonsense springs from. o_O ).

For the OP: All that stirring! Blow that 'cos it sounds like hard work to me. I mix well at the beginning (so there is none of those dry - "dough" - balls floating about) and then leave well alone. (In the "olden days" they would stir continuously for a while - which is where the word "mash" comes from). I don't squeeze the bag (well it's rigid so I couldn't if I wanted to), just allowing to drain while boiler comes up to boil ("sparging" = "more work"). Grain crush is frequently preferred to be on the "fine" side for BIAB but doesn't have an enormous impact on efficiency (2-5%?). Don't worry about all that "pre-boil/post-mash gravity" phaff, that might be considered useful at a more advanced level, just your final efficiency (brewhouse efficiency) is enough, i.e. the gravity and quantity (cooled) collected in the fermenter at the end. Collecting more boiled wort than you need is what is creating your biggest "loss" of efficiency at the moment (it's not loss of efficiency, it's over dilution of your wort).
 
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A... about face. 63C (even 62C) is more for lighter bodied very fermentable worts. 69-70C is for full bodied well flavoured beers. Lower temperatures are common with the current trends in beer; even the common "average" of 66-67C would have been considered cool 100-150 years ago.

For the OP: All that stirring! Blow that 'cos it sounds like hard work to me. I mix well at the beginning (so there is none of those dry - "dough" - balls floating about) and then leave well alone. (In the "olden days" they would stir continuously for a while - which is where the word "mash" comes from). I don't squeeze the bag (well it's rigid so I couldn't if I wanted to), just allowing to drain while boiler comes up to boil ("sparging" = "more work"). Grain crush is frequently preferred to be on the "fine" side for BIAB but doesn't have an enormous impact on efficiency (2-5%?). Don't worry about all that "pre-boil/post-mash gravity" phaff, that might be considered useful at a more advanced level, just your final efficiency (brewhouse efficiency) is enough, i.e. the gravity and quantity (cooled) collected in the fermenter at the end. Collecting more boiled wort than you need is what is creating your biggest "loss" of efficiency at the moment (it's not loss of efficiency, it's over dilution of your wort).
That's very useful thanks. I'm relieved and now excited to get another brew on the go (should be this weekend one I've got a batch out of the fermenter). I'll try and get more boiled off and take on the advice about the mashing.
 
Temps too low at 63c for a full bodied beer like a stout i think, the other thing is that are you sure that when you put the bag in at 65c the temp only drops to 63? Mine drops a lot more than that, I usually heat my water to about 73c and then put the bag in. However as Steve said 1044 doesn't sound too bad to me.
I've been mashing in at 71-72.5c and found it doesn't drop at much as expected, about 2-4c. That's at 23L/4.5kg
 
I'll get the thermometer into the mash then and see how it looks in amongst the grain. I've been relying on the probe in the water below the grain which is obviously not cutting the mustard. The mash isn't particularly thick but best to check I guess!
 
I'll get the thermometer into the mash then and see how it looks in amongst the grain. I've been relying on the probe in the water below the grain which is obviously not cutting the mustard. The mash isn't particularly thick but best to check I guess!
Don't do it! There lies madness, I should know, although it probably wasn't trying to get a temperature from my mash that caused it, but it could have been?

Best policy is go with whatever you think works and is fairly consistent, and treat with suspicion whatever anyone else is claiming.
 
Hi all,
Recently got into brewing and am really enjoying it.
This is important and not to be underestimated! :laugh8:

Any help, critiques, tips or mockery are very welcome.
Not at all, we all had to start somewhere athumb..

Now then, there's a few things jump out at me.....

I notice that your grain bill is 11.8% "oats". I'm assuming that's flaked or rolled oats (like porridge oats). Now I made this mistake again the other day (I really should know better from previous brews! aheadbutt), but I find oats makes the grain in the bag go all gluey and slimey, hence if you BIAB it's really hard to squeeze the bag out effectively (and if you don't BIAB I believe it makes a stuck sparge more likely).

From my experience the solution is to do a mash rest at 50degC - I've done 15-30 mins in the past which solved the problem, before raising the temp to 65degC or whatever.

You mention 26L water - did you add it all at once? If so that's called a "full volume mash" or "no sparge" - nothing wrong with that...

Conventional wisdom is you mash with approx. 2.5-3.5L/kg, so for your 4.25kg grain bill you'd use about 12-13L water for mashing and then sparge with the rest.

Now having always done it the "conventional" way since I started brewing ~1 year ago, I've just switched to full volume mash/no sparge. The good part is it's so much less faff, but one side-effect is my efficiency went from high-70's to mid 60's...

...but now factor in the "oats go gluey" effect on my last brew and my efficiency dropped to mid-50's!!!

Pros & cons to both approaches - one isn't more right than the other, do what works for you.

Re. mash temp - as others have already said, for a stout you'd probably mash about 67-68degC typically. But hey, it's your beer, do what you want wink... You won't break the beer mashing at 63degC!

Now here's the thing - the grain cools the water when you mash in, so as you've seen the strike water needs to be a bit hotter. There are calculators for this, but typically your strike water wants to be 5-8degC hotter than the mash temp (depends a bit on your gear and other factors). But this is only true if you do it the "conventional" way above!

If you do full volume/no sparge then the difference is much less - in this case your strike water only needs to be maybe 3degC hotter. So, assuming you did a full volume mash, if you were aiming to mash at 63.5degC then your 65degC strike temperature was about right.

Stirring the mash - as others have said, not necessary, at most give it a stir at half time and check the temp if you want to. Otherwise you can leave it alone.

Bag squeezing - this is good, I was advised to do this when I started, never noticed anything bad. It can be hot (especially if you do a dunk sparge) so get yourself some marigolds. I think in this case you just got tripped up by the oats making it gluey and harder to squeeze.

Don't sweat it about the numbers - they'll be all over the place in your first few brews as you fine tune your process, and you'll get caught out by things you didn't know about before (like oats!).

And at the end of the day numbers don't mean much - you've got a load of beer in the FV at 1.044, that's perfectly respectable and will more than likely make good beer - if it doesn't turn out exactly as you wanted just think about it and what you'd do differently next time.

As someone reminded me the other day, if you stick to the basics it's really hard not to end up with some sort of beer - beer just wants to be made.

Good luck and keep us updated athumb..
 
Hiya,
One way to increase efficiency is to mash overnight, the downside to this is keeping heat loss, so steps are needed to keep this to minimum.

I did my first 10L BIAB recently, (I'll post my brew day experience) I did an overnight mash (12hrs), 10min sparge @ 80°, boil 60 mins, and no chill. my efficiency was better than 80%.
Brewers friend @ 80% effciency had OG 1055 FG 1015 i got OG 1058 FG 1011.

Cheers
 
I have a similar BIAB setup and my process is to let the bag hang for a few minutes then sparge with 4L of cold water (just pouring it over the grain basically) then squeeze my bag like it owes me money. I've found doing the sparge with cold water makes squeezing easier since it reduces the temperature of the bag to something I can comfortably touch. I guess it takes longer to get back up to the boil though.

I'm not the most experienced brewer myself but I wouldn't worry about absolute efficiency too much, what you want is consistent efficiency between batches so you can prdict what you're going to get out.
 
Hiya,
One way to increase efficiency is to mash overnight, the downside to this is keeping heat loss, so steps are needed to keep this to minimum. …
Careful with that one. Especially with me on the thread 'cos I'm very likely to pick up on those ideas (like here). I've sort of made it my mission to put right where I can.

The brewing processes are "biological" yet we can't help thinking of them as "on-off" computer science like processes. At the temperatures we mash at the enzymes are being relentlessly destroyed, so by half-way through the night enzyme activity has pretty much ended and all the conversion is done anyway. The slow cooling down of the mash helps keep that enzyme activity going a bit longer, but there's no reason why over-night mashing should produce higher efficiencies than can be achieved with a couple of hours … less even. The best reason to over-night mash is convenience (if you find it convenient).



While I'm on my high horse: There's been many mentions of sparge temperature. The temperature doesn't matter so don't get hung up on it. Some folk get on fine with cold water. I use hot water, but don't care much about the temperature (e.g. left over strike water kept back in a bucket). There may be something in using water that is "too hot" but it is unlikely to have water at 80 degrees plus hanging about anyway. I'll often brew "no sparge" but capacity doesn't always allow that.

"But sparging is what the commercial breweries do". Yes, they also used to do multiple mashes (and no sparge) and whiskey distillers still do. What commercial outfits do doesn't indicate what's best to do.

For many decades I used to strive to have sparge temperature "just right" so I didn't always practice what I'm preaching. I brew much better beers these days, although I don't think for a minute it has anything to do with the random sparge temperatures I now use (or "no sparge" when I can do it).
 
The all-grain police will be on to me in a flash, so I’ll only say this once...

If you’ve not hit your efficiency targets or have overdiluted you can always *whispers* add some malt extract.
 
Careful with that one. ..
Hi Peebee
Duly noted, thanks for the info, showing my ignorance there, I'm very new to brewing, thought I was helping.

Please retract my statement, (can't seem to edit it for some reason)
Cheers
 
Thanks for the help all.

Had a brewday yesterday attempting an IPA. I ended up with about 13L in the fermenter with OG of 1062. I'd have gotten more in but using as much hop pellets as I did left a lot of material floating around and I struggled to avoid disturbing it with the siphon. Seems tempting to get a strainer in there and use whole hops instead in future but I'll have a read around and see what the options are.

Only major issue yesterday was the element on my Peco boiler burnt again, I think this is from the heat up to the boil rather than the mash but it's hard to tell. One to work on for next time. I gather the best approach is to keep the wort moving while it gets up to temp.

Feels like progress and hopefully I'll have a decent strength hoppy IPA to get bottled up in a couple of weeks!
 
I put my hops in a fine mesh bag...seems to do the trick athumb..

Hope it turns out well
Cheers
 
Hello all.

Gradually getting my brew days more streamlined but I'm still finding basic issues and don't think my knowledge is up there yet to fix them quickly. Any input would be much appreciated as always.

I had another brewday yesterday and was aiming for a SMASH Simcoe IPA.

I've enjoyed the last two pales I've brewed although I detect a hint of something a bit mediinal in there and I have a suspicion it was either my cleaner (chemipro oxi) or chlorine in the water. So this time I have used half a Campden tablet in my water before mashing for the first time.

I mashed for 80min at 65C. 6kg MO crushed grain in my Peco boiler with 26L of water. The grain seemed to be well mixed and moved around OK when stirring (I stirred it all in well, did one stir when checking on it after about 60min and then stirred before I pulled out the bag). After a good bag squeeze I had about 22L pre boil. I got it up to temp and boiled for an hour and was left with around 18L in the boiler. Once cooled I took the gravity reading and ended up with an OG of 1.052 when I was expecting up close to 1.07 based on beersmith. Any ideas where I'm going wrong? I think the temp is at the top end for an IPA but doesn't appear problematically high?

Ended up with a decent amount in the fermenter and should have a nice hoppy pale of 5+% for Christmas. So I'm not too annoyed but really want to get to grips with the set up so I can know what I'll get out the business end :)
 
I think the difference between what Beersmith predicts and what you actually measured is down to efficiency - I did a quick check in Brewer's Friend as I don't use Beersmith, but it defaults to 70% which also gives an OG of 1.07. If I reduce efficiency down to 49% I get your actual OG of 1.052.

(that sounds very low to me but perhaps someone with more experience can comment?)

Now if I understand correctly you're doing a full-volume/no-sparge mash, right?

I recently switched from sparge to no-sparge and saw my efficiency drop from ~75% to ~65%. But it makes my brew day much simpler, and I can compensate by adding a bit more grain to get my desired OG.

However, I do 10L batches - so the extra grain I need to add is less and also the fact that I'm using a lot less grain than you overall means I can probably get a more effective bag squeeze (when I've done big beers with more grain I've struggled to get such an effective bag squeeze).

So you have a few options:
  1. Just live with it! But set a lower efficiency in Beersmith next time so there are fewer surprises. Efficiency is just a number. It's not something to worry about. Personally I'd be perfectly happy with a 5% IPA, but that's just me!
  2. You can add more grain - but a quick check says you'll need >2kg extra maris otter to get back up to OG=1.070 which may be a bit costly.
  3. You could do a dunk sparge as I used to do - it's an extra step but not actually hard (I'm just lazy and impatient!) and might win you some more efficiency.
  4. Squeeze the bag even harder! Mind you it's hard enough with just 3kg wet grain so good luck with your 6kg!!! I've found if you hold the top of the bag and keep twisting it round and round, squuezing now and then as you go, it really wrings the bag out.

Main thing is not to sweat it too much. It's a hobby so make sure you enjoy yourself - you just need to decide if "enjoy" means saving time, saving money, having stronger beer or whatever.....
 

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