Sh*tty Efficiency

[floydmeddler]

First time brewing with lager malt and my efficiency was 71%. Same thing has happened to my last ale brews too. Ending up at around 71%-73%. This has just started happening! I used to get at least 83% every time!

Any ideas? Have changed nothing about my method AT ALL.

[harry_mac]

Obviously something else has changed if it isn't your method. Things that spring to mind are the quality of the grain (unlikely as it's a problem with 2 malts), scales or thermometer giving incorrect readings, or as a long shot water alkalinity.

[pantsmachine]

My efficency went through the floor with my last sack which was lager malt. Back onto marris otter but not brewed with the new sack yet. I'd put it down to the grain.

[floydmeddler]

Yes, hopefully that's it.

Pain in the arse though. Feel like I've gone from hero to zero.

[pantsmachine]

I know what you mean. I think i went from 80/85% on my last sack of MO to 60/70% with the lager malt. Just as i'm getting used to chucking in the extra KG or so of grain the sack comes to an end! I suppose you could try an extra 1/2 hour onto your mash time?

[yashicamat]

I get the same efficiency with lager malt as I do with MO, so I am slightly sceptical that the grain type is the sole cause . . . that's not to say that you had a poor quality sack of lager malt, though. What was the run-off like? Was the mash completely free of lumps? I would think the latter could be a real possibility (not doubting your ability to dough in by the way, but I have noticed some malts seem to dough in with little effort while others form golf balls of dry grain for fun).

[floydmeddler]

Well,

I mashed in with no dough balls and it maintained at a steady 67c for 90 mins. I then batch sparged. The gravity of the very final runnings was 1020. I didn't take a preboil gravity reading.

Although I collected 23.5L in the fermenter, I didn't take into account the 1L extra that didn't make it to the boiler and the 2.5L that was left behind in the boiler due to hops and trubs. Don't know if this makes a difference. Efficiency CONFUSES me.

Wish I had have taken a preboil reading then I would at least know my grain efficiency.

So, I've got a 4.4% Belgian Pale Ale. How embarrasing. Might add some sugar.

[leedsbrew]

Strange that you guys found a decrease in your efficiency when using larger malt, as i just used it for the first time and my efficiency went from a standard 79-80% up to 95.1%. Are you using 100% larger malt of other malts as well. My 95.1 comes from here, which was a 50/40/10, wheat, larger, munich, weiss. Did you get your larger malt from your usual supplier of MO? Could it be from a different maltings? or have been milled finer/courser?

[yashicamat]

Well,

I mashed in with no dough balls and it maintained at a steady 67c for 90 mins. I then batch sparged. The gravity of the very final runnings was 1020. I didn't take a preboil gravity reading.

Although I collected 23.5L in the fermenter, I didn't take into account the 1L extra that didn't make it to the boiler and the 2.5L that was left behind in the boiler due to hops and trubs. Don't know if this makes a difference. Efficiency CONFUSES me.

Wish I had have taken a preboil reading then I would at least know my grain efficiency.

So, I've got a 4.4% Belgian Pale Ale. How embarrasing. Might add some sugar.

2.5L in 23.5L is over 10%, which is significant . . . but do you not normally take this into account with your calculations? 1L that didn't make it into the boiler I'm assuming will be about 85% of the gravity of the post boil gravity, so the equivalent of having about 0.85L missing from the FV (assuming a constant trub / hop wort loss).

Next time take note of the preboil gravity and the amount of wort collected - you can use this to calculate your efficiency. Try a simple recipe with just 90% lager and 10% wheat or something so it's easy to work out, there is info about on how to do this (John Palmer covers it on his website but it takes a bit of digging).

I'm actually lazy these days and can't be bothered to sanitise hydrometers, trial jars and jugs etc. to take a "proper" OG, so I just measure the OG of what I've collected in the boiler (after being stirred thoroughly as I fly sparge) and note the volume, then note the final volume when I've finished and calculate the OG from that (i.e., preboil volume in litres x preboil gravity points, then divided by postboil volume in litres to give my postboil gravity points). I can check my efficiency against my predictions in beer engine then . . . I was getting 83% as regular as clockwork but since I've been modifying / rebuilding bits of the brewery, the efficiency has been like a yo-yo. Just settling down now at last at about 85% which is a relief after modifying all that kit!

[floydmeddler]

I used to do a preboil reading religiously. However, my current boiler doesn't have markings so I stopped checking. Today (if my order arrives) I will transfer it back into the HLT which I have marked litre by litre.

One thing which has really got me thinking is the fact that the very final runnings were 1020 meaning the sugars weren't properly rinsed. This is quite high. I've also been noticing the wort 'draining' down one side of the mash tun meaning it's not actually going through the grain bed.

In fact the more I think about it the more it's starting to make sense. Recently, my false bottom slides in to the MT with no force needed. When I was hitting the 80's I had to gently force it in ensuring a really tight fit.

This must be the cause!

[pantsmachine]

Glad you are getting towards a result. Interested about your Heather ale. Did you go picking?

[floydmeddler]

Just rethinking this and it doesn't actually make any sense! (Too early in the morning) If the wort was running down the sides and not being filtered through then it wouldn't be 1020 at the very end. It would be much less as it hasn't really 'rinsed' anything... right?

SO, why am I not rinsing the sugars? Why do my very last runnings have such a high gravity? Or is 1020 normal for the very last runnings?

I will conquer this!

[floydmeddler]

Glad you are getting towards a result. Interested about your Heather ale. Did you go picking?

Hi. Here's the thread I did on it:

viewtopic.php?f=2&t=25500&p=280494#p280494

Yep, I picked it back home in Ireland. Next time I'll use WAY less heather and NO bog myrtle. Will add hops to bitter only.

[Barley Water]

Just a few ideas for you:

The first thing I would look at is the grind. Especially if you get your grains ground by the supplier, they may have changed something without you being aware of it. For instance, if you use 6 row malt (or wheat malt) your efficiency will go to hell unless you make some adjustments (of course don't go too far as I did in my last brew session and get slow runoff). If you grid you own, check out the gap on the rollers, maybe they came loose somewhere along the way giving you a lousey crush.

The next thing has to do with the pH of the mash. If you have water that is slightly alkaline, the pale lager malt can not over come that and your mash ph tends to be too high messing up your efficiency. If you notice you do better when making darker beers that may be part of the issue. I have this situation so I always use the Acid 5.2 stuff (which is a buffer) therefore I don't need to worry about that and can concentrate of screwing something else up.

Finally, if you fly sparge and for whatever reason you get channeling, your efficiency can drop like a bomb. I highly recommend batch sparging which of course has been discussed on this forum ad nausum. Long story short, you don't need to worry about channeling if you batch sparge and it's easier to keep the pH in the right range while running off therefore avoiding the extraction of unwanted tannins.

I guess at the end of the day though, since we are dealing with grains produced by nature, we should expect some variation. If everything went perfectly every time, things would get boring, right?

[floydmeddler]

Just a few ideas for you:

The first thing I would look at is the grind. Especially if you get your grains ground by the supplier, they may have changed something without you being aware of it. For instance, if you use 6 row malt (or wheat malt) your efficiency will go to hell unless you make some adjustments (of course don't go too far as I did in my last brew session and get slow runoff). If you grid you own, check out the gap on the rollers, maybe they came loose somewhere along the way giving you a lousey crush.

The next thing has to do with the pH of the mash. If you have water that is slightly alkaline, the pale lager malt can not over come that and your mash ph tends to be too high messing up your efficiency. If you notice you do better when making darker beers that may be part of the issue. I have this situation so I always use the Acid 5.2 stuff (which is a buffer) therefore I don't need to worry about that and can concentrate of screwing something else up.

Finally, if you fly sparge and for whatever reason you get channeling, your efficiency can drop like a bomb. I highly recommend batch sparging which of course has been discussed on this forum ad nausum. Long story short, you don't need to worry about channeling if you batch sparge and it's easier to keep the pH in the right range while running off therefore avoiding the extraction of unwanted tannins.

I guess at the end of the day though, since we are dealing with grains produced by nature, we should expect some variation. If everything went perfectly every time, things would get boring, right?

Yup! That is right. Part of the excitement is the 'not knowing how it'll all turn out' thing. I'm going to buy some PH strips and concentrate on that for my next brew. This current brew is doing OK now actually. I added 500g of homemade Belgian Candi Sugar which upped the alcohol content a bit so I'm now in the correct range for this style.

Cheers for the advice.