Drop in efficiency a technique issue?

[droid]

Morning all,

I've started step mashing but have also begun doing some decocting. So I have been decocting to hit a rest temp then recirculating to hold it.

The last batch had a stuck grain bed from recirculating too fast - does that usually result in a drop in eff? The lower rest of 62/10mins ended up being 62degrees or less for 20-30 mins while I transferred all the grain out

The mash schedule was 57/5, 62/10, 67/50, 72/20, sparge 78
Because of the stuck mash at 62 I did 68-69/50 mins, was that a mistake?

Yesterday I had a complicated decoction mash but after a change in plans from a phone call I ended up just doing the same as above with no problems except I used 100% Gladfield lager light

In the software I recently raised my efficiency from 75 to 82.5 after some good mashes at single temp infusions, no stepping, slow recirc...

After the 2nd last brew I changed back to 75 but still had a drop from an expected OG of 1053 to 1047, that does include just under 5% more wort in the fermenter after the boil so not that far off I spose

I'm doing a double batch of the same brews next week so a bit concerned about getting this sorted

?

 

[manticle]

Decoction and stepping, if done properly should result in same or higher efficiency.

Do you need to decoct to step? Maybe you're denaturing too many enzymes, too quickly. Can you explain your process from step to step?

 

[droid]

Ah ok, I'll get the kids off to school and report back, thanks

 

[Reman]

Can I ask what you based your temp/time schedule on?

The lower sacc rest seems a bit short, then there's one in the middle that most don't have.

 

[manticle]

62 for 10 followed by a very high 60s (I'd tend towards 69) will produce a beer that attenuates well but still retains good body and mouthfeel. If I want a drier beer, I'll push my beta rest to 15 mins but it doesn't need loads - the next rest will still continue some beta activity, just not optimised and starting to denature.

 

[manticle]

Although 57 is a bit no man's land - try 52-55

 

[droid]

Maybe it was sposed to be 55. Also I wanted it dry so I did 62/10 then 67/50, instead of 63/10 and 68/50 but after the long rest down low I thought bumping it up at the other end was needed.
It was a marzen and the desire was for a malty sweetness initially that fades to a dry finish. I was trying to pull out the malty flavour from the decoction but mash for a dry beer, it was Munich/pils/xtal at 44%/53%/3% roughly because I am on the iPad and too lazy to check exactly right now, will do if needed

The schedule was from a bloody good brewer who shall remain nameless less he speak, he mentioned skipping the 63/10 as an option and my 62/10 was his 63/10 as was my 67/50 instead of 68/50, now I'm remembering thinking I'd do it at 66/50 but changed because of the dramas at 62

It was a ratio of 3ltrs water to 1kg grain in the mash - should this be different for decocting?
I think I did a little decoction from 55 to get to 57
Then another one to get to 62, it hit 60 with the decoction then I used the HERMS to get the other 2 degrees
Then decocted again to get near 67 with another recirc through the HERMS to get to the 68/69

I nearly got a stuck grain bed again during the long rest and had to fluff the mash up which was quite hard, could it just simply be that those times when the mash bed was nearly solid has caused the lack of conversion or could it be that when I use the HERMS something's wrong

Could be simply not enough grain

Yesterday was 5kg for 22ltrs of 5.16% does that sound right, maybe my numbers are all stuffed up

Apols for tangents and typing I gotta get off this stupid iPad and do a quick 200km trip for co2.......d'oh

 

[Reman]

You say little, how big is the volume for your decoctions?

 

[droid]

the first one was thin and only 3 liters (approx) to get to 57
then maybe another thin 3 liters to get to 62 (approx)
then a thick 5-6ltr (just over 33%) mash which i think i just got to boiling to get to 67 which as said went to 68/69 because of the stuck mash
was there really a fourth to get to 72 or did i just HERMS it? - jeepers

i didn't really note the exact amount...cough - i had read 30% and that it should be thick?

maybe i need some lessons in decocting, though that wouldn't help the last batch which was steps but not decoction

 

[droid]

btw this wasn't formed from any advice...so that may be the issue...or one of the issues

 

[MHB]

Generally a decoction brew is mashed in thinner (4+:1), give it some time for the enzymes to get into solution, then get the thick stuff from the bottom for the decoction (I find a soup ladle works well).
Most of the enzymes will be in the wort above the malt, there will be enough in the decoction to do what needs doing - heat the decoction slowly to around 67oC - let it rest at that for 10 minutes or so then heat to a boil and simmer for another 10 minutes before returning it to the mash.
One of the reasons to decoct a thick mash is to gelatinise the small gradual starch and to break down more protein, and to still have the enzymes needed to further degrade them still working in the main mash when the decoction is returned.
Thinner mashes are also better for light dry beers, thicker mashes favour higher body beers.

Decoction brewing is slow and tedious, but the best home brewed pilsner (and not just home brewed) I have ever tasted was triple decocted bohemian pilsner.
Worth the extra work
Mark

 

[droid]

thanks guys the questions and thoughts are appreciated. next week will be decoction with no recirc until mash out i think
Mark I will take your advice and go for a 4:1 ratio, thanks for the reply and the explanation, there's something nice about decocting though i can't explain the feeling
pilsner urquell's mashing regime is intriguing, maybe i will try it with both the marzen next week and the pils - just need to get going really early!

MASH GUIDELINES:

1) Temperature, Temp: 38 C, Time: 30 min
2) Decoction, Temp: 65 C, Time: 10 min
3) Decoction, Temp: 72 C, Time: 10 min
4) Decoction, Temp: 100 C, Time: 10 min

5) Decoction, Temp: 65 C, Time: 10 min
6) Decoction, Temp: 72 C, Time: 10 min
7) Decoction, Temp: 100 C, Time: 10 min

8) Decoction, Temp: 72 C, Time: 10 min
9) Decoction, Temp: 100 C, Time: 5 min

10) Sparge, Temp: 77 C, Time: 20 min

 

[MHB]

Being a fairly pictorial thinker, I found this a good way to look at decoctions. This is for a bock I was working on a few years ago, brewer in parallel on both a braumeister and by triple decoction.
Not quite the classic 38-50-65-72oC triple decoction nor the 50-67-77oC double decoction but worked pretty well for a bock.

If you want to play around with the graphing here is the Excel spreadsheet that generates it.
View attachment Triple Decoction.xlsx

The thinner the mash the bigger the decoction, if you are heating mostly the heavy part, proportionally more of the grist is getting boiled so you get more complete starch gelatinisation, as well as more break down of cytolytic structures - giving better yield and it has some interesting effects on the flavour profile.
Mark

 

[droid]

that's awesome Mark - what a champ!

I think i will copy some of this and put it up on my facebook page ~ Tower 3 Alehouse, if you don't mind.
Ive started that page to collect not only memories but a place to store info

awesome stuff mate thankyou

 

[Adr_0]

I think you should still be recirculating if you can.

I use a 2000w induction cooktop - portable, 1m from a power point... - and per MHB's advice i scoop out the grains, permitting only enough liquid to have some in the saucepan and distribute heat.

The actual decoction is rich in protein and starch (I assume) as it's significantly cloudier coming back in.

If you gently 'swim' it back in you minimise grain bed disturbance. I have generally had good run off doing this.

I think you definitely need to recirculate to help your efficiency, temperature distribution and clarity. You should try to do this for the rests and to trim temperature when adding back in, and definitely have to do for mash out.

I had 84% mash efficiency with 75% Munich II and single batch sparge. As manticle said you should be meeting or exceeding normal efficiencies.

 

[Reman]

Thinner mashes are also better for light dry beers, thicker mashes favour higher body beers.

Im wondering why that might be the case?

I thought it might have something to do with mash ph, but in a water calculator even doubling he mash water didn't move the ph much (17l to 30l went for. 5.2 to 5.27).

 

[MHB]

Its down to enzyme activity, in a thick mash Alpha Amylase does more cutting than does Beta - gives more higher saccharides - sweeter beer.
There are a few other things going on, protease activity, pH, Calcium content, temperature... all play a part.
As you noted adding more water will raise the pH (well actually move it toward the pH of the water), but not by a lot.
Mark