Saving time/overnight mashing.

[Lyrebird_Cycles]

If you rest too long at beta, there'll be nothing left for alpha.

To quote Briggs

The extensive degradation of starch that occurs during mashing depends on the concerted action of the mixture of enzymes present and is often limited by enzyme destruction rather than the absence of substrates for possible enzyme attack.

(Briggs et al, CRC Handbook of Malting and Brewing Science 2004 p 147)

A very long rest at beta will result in there not being any active beta left by the end of the rest.

 

[manticle]

I have access to an electronic copy of briggs somewhere (somewhere slightly annoying) but can you elaborate?

I'm interpreting that beta will denature before it breaks down everything beyond alpha's reach? So even a 3 hr rest at 62 (for example) may leave starch that alpha can convert to dextrins?

Presumably (based mostly on my palate and personal experience of step mashes) - not much in real terms to balance what will be a very attenuative wort.

 

[Lyrebird_Cycles]

That's the theory, backed up by recent experience: Moving from a six hour mash to an eight hour mash increased fermentability eg it reduced FG from >1 oP* to about 0.7 oP. Next up I'm trying 12 hours to see what I can get. I don't think I'll be able to get under 0 without enzyme but at least I'll have tried.




*Somewhat shamefacedly I must admit to not having measured this properly.

 

[Coldspace]

One thing. I have done this with 40lt brew. Turned off the keggle. Left sit overnight then brought back to boil the next morning and I got a scorched bottom. Wort left to sit that long there was sediment. Then cranked up the flame and burned the sediment cake.
So in hindsight I needed to stir up the bottom well before cranking up the heat.

Tks for the tip, might have saved me a lot of cleaning and lack of boil.
Cheers

 

[Zorco]

To quote Briggs


(Briggs et al, CRC Handbook of Malting and Brewing Science 2004 p 147)

A very long rest at beta will result in there not being any active beta left by the end of the rest.

What happens to the enzyme causing its destruction?

 

[MHB]

Enzymes will work for a long time cool and slow, as they get hotter (from what is called activation temperature) they work faster but denature sooner. Apparently they will do the same (or close to the same) amount of work in total. But at some point they just fall apart.
Have read that it would take about two weeks to "mash" at 20oC, naturally by then the mash would be hopelessly infected.

For each enzyme there is an optimum temperature and pH, in any mash we will be compromising between the various enzymes ideal conditions to get them to do most of what we want, in a timely manner. There are also a hell of a lot of enzymes that we don't use, or even want to see too active (i.e. Gamma Amylase 3pH peak, lipoxidase, some of the proteases... )

Mark

A bit of light reading
View attachment 09 - The role of enzymes.pdf

LC why would you want a beer that dry? unless you just wanted the alcohol from it.
M

 

[Zorco]

I have access to an electronic copy of briggs somewhere

http://www.mbaa.com/districts/Northwest/Documents/MISC/Books/BRIGGS,%20Brewing%20science%20and%20practice%20(2004).pdf

 

[Zorco]

To quote Briggs


(Briggs et al, CRC Handbook of Malting and Brewing Science 2004 p 147)

A very long rest at beta will result in there not being any active beta left by the end of the rest.

document p133 of link above, physical pdf p153

 

[stuartf]

Not trying to kill the experimental theme of the conversation here but has the OP thought of buying the new grainfather controller which allows delayed start times and auto step mashes? May not be as much fun but would take some of the guess work out of it.

 

[mr_wibble]

[...]
66 may be hot enough to kill lacto - I'm not sure but 77 will definitely be*. Pasteurisation also happens much more quickly at higher temps and 77 is well above recommended food pasteurisation temp (66 isn't, 65ish is the upper end at which some spoilage bacteria can actually grow).

[...]
*some lacto strains may be tolerant to even these temps - not sure if these strains are present in grain or not. Ultimately if you end up with soured wort, you'll know why.

Listening to some podcasts on (intentionally) sour beers, it sounds like hops (even unboiled) are particularly good at inhibiting lacto'.
Maybe some mash-hops would hinder/prevent infection by lacto' over extended mashing periods.

 

[klangers]

Hotter you keep the wort, the less DO problems you'll come back to later.

If your house is smelling of malt, some of the malty flavour goodness has oxidised .

 

[Tony121]

If your house is smelling of malt......

That's my favourite part of the brew day, please don't take that away from me!

 

[Moad]

going to approach my process differently tomorrow to see if I can get a mid week brew with no complaints...

Have filled the vessels and milled grain tonight, planning on "mashing in" when I leave for work at 7 (25c).

I'll set the BCS to start my strike process and tell it to move on to the first mash step automatically when it hits mash step 1 temp rather than strike temp.

It will go through the steps and then I will hold at mash out until I get home, I could be done by 7pm!

I could use this over night as well to save my 5.30am wake up call for mash in.

Once I add two float switches in (one in HLT to turn off the pump and the other in the BK to stop sparge when full) I'll be able to automate the sparge process as well meaning I can mash in when I go to bed and wake up to the start of the boil.

 

[RobW]

There's been a fair bit of discussion on the Braumeister forum about this and it certainly makes for a short brew day and increased extraction.

link

another link

 

[Moad]

Well mash looks to have gone well, it is now sitting at mash out waiting for me to get home.

Planning on kicking off the sparge (regulated with a blichmann sparge arm) as I am leaving work. I forgot this one is a 90 min boil so will be done and cleaned up by 9pm.

Will report results back

 

[Lyrebird_Cycles]

66 may be hot enough to kill lacto - I'm not sure but 77 will definitely be*.

*some lacto strains may be tolerant to even these temps - not sure if these strains are present in grain or not. Ultimately if you end up with soured wort, you'll know why.

To work out the heat death for an organism you need to know the D value at a standard temperature (time taken for one log cycle, eg population to reduce to 1/10 initial value, normally at 60 oC for organisms of interest) and the z value (temperature increase required to reduce D value by a factor of 10).

Streptococcus thermophilus is used as the standard model for spoilage due to thermophilic LABs; as its name implies it's very heat tolerant. Highest D60 value I can find is 8.3 minutes, accompanied by a z value of 6.2oC . Highest z value I can find is 12 oC, accompanied by a D60 of 2.2 minutes.

Taking a worst case scenario and combining D60 = 8.3 minutes and z = 12 oC to get D66 = 2.5 minutes (8.3 x (log (6 oC / 12 oC)), it would take 15 minutes to reach 6 log death, the accepted value for functional sterility.

In case you were wondering, both D and z values are pH dependent but the figures I quoted are at pH 7, at mash pH they will both be much smaller so death will be quicker.

BTW last week I mashed for 8 hours at 60 - 66 oC followed by 2 hours at 68 oC * There was no lactic influence that I could discern.



* It was meant to rise continuously from 62 to 70 over ten hours but the heater turned off while I was asleep.

 

[manticle]

Good to know. I assumed it should be fine but we all know about assumptions.
Incidentally, when writing that post, I did some quick checking and I'm sure I found reference to some lacto strains surviving north of 77, hence the caveat ( not sure which strains or for how long).

Haven't been able to find the study again though, so maybe it was a dream.

 

[droid]

^clouds in your coffee?

 

[A3k]

[SIZE=medium]I did a few experiments mashing in cold with the aim of overnight brewing, but I struggled with the circulation and had enough stuck mashes that I didn’t have enough confidence to do it whilst away from it. Not major stuck mashes, but needed manual intervention.[/SIZE]

[SIZE=medium]This may be different on a Braumeister or GrainFather though. My mash tun is a keg with false bottom, with a HERMS and controller I made. I also get my homebrew shop to mill my grain, and haven’t played around with milling. If I get a stuck mash, my element could run flat-out and cause a boilover of the heat exchanger.[/SIZE]

[SIZE=medium]I hadn’t thought about keeping it at 78 before though. It does open up a few opportunities.[/SIZE]

[SIZE=medium]Cheers,[/SIZE]
[SIZE=medium]Al[/SIZE]

 

[Stouter]

a reason I got my bro to invest in a gf and another kegmenter , so we can keep up..

Well done with getting your Brother to invest in a Girlfriend and another kegmenter. Great investment there.
I keep telling my Brother that he can never have too many Girlfriends and kegmenters, he just calls me a fool, as you may well do also.