The Long March From 55 To 75.

[Screwtop]

So, because you're using a lesser amount of water (than, for the sake of the argument, me), to raise the lower temperature grain to your desired mash temp, you have to heat the water to a higher temperature. As this high-temp water hits your grain, some of the enzymes are subjected to 'mash-out' temps. Not so bad for the beta-amylase, but seriously annoying for the alphas.

Lots complex sugars, fewer simpler sugars. Unhappy Screwtop.

Bingo Spills, wish I could have explained it so simply

Screwy

 

[Kai]

Don't you mean higher temps are badder for beta and not alpha? beta-amylase prefers the lower temp range.

Regardless, I don't see higher strike temp water affecting wort attenuation that much. Any conversion products made by alpha-amylase at higher temps during the first ten minutes will just be further digested by both amylases over the course of the mash. Not to mention that beta will still be active and producing maltose during the higher initial temperature phase; it's just also denaturing at the same time.

 

[roger mellie]

Makes the brewday less boring too. B)

Warren -

Hmmmmm - I guess that is one way of looking at it Warren. Looks like a pain too me.

I'm still on my Esky Mash tun - single step phase - very rare for me to drop below 78% - usually 80%.

I dont have the gear to do this 55 rest as yet - I will get there. This will be a complete change - with Herms and a 50L mash tun. Im interested in the difference but apreshensive that it will turn a simple regime into a 'fraught with peril' one.

RM

 

[blackbock]

Screwtop, I think I understand what you are saying, and don't take this the wrong way, but why do you need to infuse at such a high temperature??? 9 degrees above mashin temp would be way too high on my system, usually the difference is more like five or six for me, obviously that will vary due to various factors, but it seems to me that a simple answer would be to try a lower water temperature...Probably stating the obvious though.

 

[jimmyjack]

I was getting chronic high finishing gravitys around the 18 mark. My last beer I mashed in at 55 held for 15 minutes raised to 65 held for an hour and then mashed out. The finished product is noticably dryer and as an off shoot has much better head retetention.


Cheers,


JJ

 

[Screwtop]

Don't you mean higher temps are badder for beta and not alpha? beta-amylase prefers the lower temp range.

Regardless, I don't see higher strike temp water affecting wort attenuation that much. Any conversion products made by alpha-amylase at higher temps during the first ten minutes will just be further digested by both amylases over the course of the mash. Not to mention that beta will still be active and producing maltose during the higher initial temperature phase; it's just also denaturing at the same time.

Kai,

Spills response was near enough, think he was on the right train of thought anyway :lol:

These are my findings after seeking and following advice. The advice was that this could be a problem with high enzymic malts with my system and process and that it may not be the case with all malts. Am simply passing on my findings using my equipment. When I was underletting I was having more of a problem often I would need to have strike water in the high 70's to allow for losses (pump/piping and SS tun), depending upon how long the pump took to prime the temp of the water arriving in the tun varied and achieving the desired Sacc rest temp was a bit of a hit and miss affair. Still underlet though as this is how the sysem is designed but the grist is added after the temp has stabilised and the tun has heated. This has been a process of elimination over a 12 month period each change producing an improvement.

This all began after chasing down a problem that I had which was contributing to low attenuation. Was monitoring the mash temp at the thermometer mounted in the mash tun. Recirculating to maintain mash temp meant that the wort was reaching temps 3 or 4 degrees hotter in the coil in the HE during recirculation. I sought the help of some experienced brewers and was advised to move the monitoring point to as close as I could to the exit of the HE coil. Making that change made a big difference but I was still not achieving a high degree of attenuation.

Changing from underletting onto the grist to adding strike water to the tun and waiting for the tun to absorb some heat before adding the grist increased attenuation further again. Now I wanted to try going the extra step and mashing in at a lower temp. Again this increased attenuation, that is my finding using my equipment. From my brew log 26/9/08 a grist consisting of 70% Pils 20% Vienna 5% Cara Pils and 5% Wheat (look familiar Tony) strike water of 76C underlet to grist in the tun, mashed at 66C for 60 min for an OG of 1.047 finished out at 1.011 fermented @ 20C using S-05. The same grain bill on 9/12/08 this time water added to tun at 61C then grist added to the water in the tun at 57C dropped after stirring to 54C began recirculation for 10 min at 55C then ramped to 66C over 15 min for a 60 min rest OG of 1.048 finished out 1.009 fermented @ 20C using S-05. AA increase of nearly 5% and happier with the mouthfeel of the beer.

Lots of others achieve higher AA% without going to these lengths, low attenuation has always been a problem for me ever since kit days, happy to be on top of it now though.

Enjoy being able to do double batches now and use two different yeasts to track attenuation and flavour/aroma contributions. Before finishing gravities were higher and all over the place, it's great, for the last six months my beers have finished at predictable gravities, much easier to plan bitterness/ sweetness balance.

Cheers,

Screwy

 

[Jazzafish]

Hmmmmm - I guess that is one way of looking at it Warren. Looks like a pain too me.

I'm still on my Esky Mash tun - single step phase - very rare for me to drop below 78% - usually 80%.

I dont have the gear to do this 55 rest as yet - I will get there. This will be a complete change - with Herms and a 50L mash tun. Im interested in the difference but apreshensive that it will turn a simple regime into a 'fraught with peril' one.

RM

You won't regret it!

After buying a pump and some clear garden hose I was able to build a herms really easy. My Immersion chiller doubles as a heat exchanger in my HLT to a passable level. Nothing wrong with alot of the hard plumbed systems and lots of valves, but I find hoses a cheaper alternative. Other advantages are line of sight and easy cleaning. Just doesn't look as pretty!

I think the results of a 55 - sacc - mash out are worth it. Head retenation was a big advantage for me. That said I also had my first dose of chill haze with a batch that held at protien for too long (distracted by a crazy 2 year old).

Another point that supports this process is that the majority of commercial brewers also use a stepped mash with the same malt.

 

[SpillsMostOfIt]

Don't you mean higher temps are badder for beta and not alpha? beta-amylase prefers the lower temp range.

Yep... :blink:

 

[Bribie G]

Conversion occuring during the 10 min or so while reaching equilibrium in my system meant that this was happening at higher temps than the desired Sacc temp. IE: mashing in using 77 infusion water, some conversion was occuring at higher temps during the time it was taking for the mash to reach 66C resulting in a less attenuative wort than if the sacc rest had been conducted for a full 60 min at a max of 66C.

Hope that's a better explanation,
Screwy

Great thread and it's exploring territory I've been thinking about.

What Screwy says is what has been 'worrying' me the last couple of brews. With BIAB I get the liquor to strike temp, which for a fairly robust 5.5 k grain bill is normally bang on 70 for a 66 mash (lower strike temp for smaller grain bills). However I pour the grain in as a thin stream whilst stirring to avoid maltesers - with my first AG BIAB I poured too quickly and was chasing big vitabrits round the urn for the next five minutes . It strikes me that those poor little malties in the first half of the pour are being scorched with liquor in the high sixties for at least five minutes.
I'm considering doing a thicker initial mash with lower strike temp then raise with hotter liquor and bring it UP to 66 or whatever rather than bring it DOWN... My Yorkies have been sweet and high attenuating which is personally to my taste but I really would like the ability to turn out something far drier such as Tetleys or TTL style.

Supplying the extra hot liqour is no problem and I'll give it a whirl on Wednesday when I do my next BIAB.

 

[roger mellie]

Just as a mater of interest - does anyone who does infusion mashing (Non HERMS/RIMS) do this 55 rest?

I dont really have an issue with attenuation - my pilseners ofter finish at 1.008/9.

But I do like the sound of improved head retention. What are my options for the 55 step - 64 infusion - decoction? My mash tun isnt big enough to step up with water.

RM

 

[RobB]

MC, I have used a modded Keg Style vessel for the past 2.5 years, mashing in using infusion around 9 higher than the required mash sacc temp in the plastic tun resulted in low attenuation, so I changed to the SS vessel. Still had the same problem, when I used to underlet it was worse. After contacting Jamil Zainasheff and some AU Commercial Brewers the advice was to add water to the tun and wait for heat to be absorbed before adding the grist. This helped but I still was not achieving good attenuation. Jamil suggested that I might use a lower Sacc temp, as high enzymic malts convert quickly and some conversion occurs during the time it takes for reaching equilibrium "a minute or two is absolutely unattainable in my system" thus the lower Sacc temp might average out a little higher (ie: Mash Sacc rest temp of 62 may avareage out at 65). I think it was Jamil who advised trying a lower mash-in temp then step using the HERMS setting the controller to the Sacc rest temp so as not to ever raise the mash temp above the Sacc Rest temp. This made an incredible difference, so the practice was adopted and I've been extremely happy with the results. The 55 rest is not designed to be a protoien rest it is just a point to start at before raising the temp.

For the BIAB guys - I never (READ NEVER) stir the mash, following the British style and rarely getting above 2.75L/Kg grist ratio. There is lots of info about if you like to google re the German style mash regimes where liquor to grist ratios are much higher, but they continually stir during mashing. Google it --- something to do with needing to stir with a watery (no-sparge/BIAB) mash to ensure enzymes come into contact with starches in the larger volume mash. So for BIAB'ers I would recommend stirring continuously following the German mashing model.

Hope this is usefull,

Screwy

Good point - I wasn't comparing apples with apples. Even when I hold back my mash-out volume, I'm still mashing with a L:G of around 4 which only makes my strike temp about 4 degrees above my sacc temp. Plus I stir like crazy.

 

[Thirsty Boy]

Great thread and it's exploring territory I've been thinking about.

What Screwy says is what has been 'worrying' me the last couple of brews. With BIAB I get the liquor to strike temp, which for a fairly robust 5.5 k grain bill is normally bang on 70 for a 66 mash (lower strike temp for smaller grain bills). However I pour the grain in as a thin stream whilst stirring to avoid maltesers - with my first AG BIAB I poured too quickly and was chasing big vitabrits round the urn for the next five minutes . It strikes me that those poor little malties in the first half of the pour are being scorched with liquor in the high sixties for at least five minutes.
I'm considering doing a thicker initial mash with lower strike temp then raise with hotter liquor and bring it UP to 66 or whatever rather than bring it DOWN... My Yorkies have been sweet and high attenuating which is personally to my taste but I really would like the ability to turn out something far drier such as Tetleys or TTL style.

Supplying the extra hot liqour is no problem and I'll give it a whirl on Wednesday when I do my next BIAB.

That will make a difference, like any variation in process will, but in and of itself it shouldn't lead to lower attenuation. Like Kai said, you might have a bit of increased alpha amalayse activity for a few minutes, but its not long enough to finish off your betas (which are also still working and working fast at the higher temps) and once the temps settle back down - the betas will start chomping away on all the extra chain ends you maybe made.

If you keep you process consistent, then all you really should need to do is tweak your sach rest temperatures up and down to alter your fermantability. You might make a slightly less fermentable beer at a given sach rest temp than I would.. but it will still be under control. Only need to change your process if, like screwtop, you aren't able to get the results you are looking for without changing it.

With a BIAB brew - Of the beers I have made and/or tasted, beers that are too dry seem to be a more common problem than beers that are too sweet. So I suspect that you probably wont have a lot of trouble making a dry beer if you want.

If I were guessing as to why the lower dough in temps help with fermentability, I would go with longer mash time, generally increased opportunity for teh beta amalayse to work, combined with better conversion of the starch due to increased stirring, or in screwy's case extra re-circulation. As you normally raise to a mashout, a bit of starch that previously wasn't converted, gets accessed and converted - except at mash-out temps, you have pretty much knocked out all the beta amalayse and the remaining activity is all alpha - which gets you dextrins and nothing much else. A more thorough mash and conversion means less starch for this to happen to.

Probably a bit of a combination of all the things people have discussed - makes no difference really - that mash regime is doing the job for screwtop, and I know its effective because its my general mash profile too. All the theorizing in the world about why?? doesn't affect the actual results.

TB

 

[warrenlw63]

Just as a mater of interest - does anyone who does infusion mashing (Non HERMS/RIMS) do this 55 rest?

I dont really have an issue with attenuation - my pilseners ofter finish at 1.008/9.

But I do like the sound of improved head retention. What are my options for the 55 step - 64 infusion - decoction? My mash tun isnt big enough to step up with water.

RM

RM I do a 55 rest without a HERMS. I just dough in with an LG ratio of 1.5 litres of water per kg of grain. It's a bit like mixing concrete but not impossible to dough in correctly with a bit of elbow grease.

Then I just infuse with 90 degree water to hit the sacc rest. FWIW I'm usually using around 9kg of grain in a 50 litre mashtun. Works more than adequately.

For the record yes, my efficiency, head retention and attenuation have all improved as a consequence.

Warren -

 

[matti]

RM

I do step mashing in 37L mashtun for 23-25 litre batches.
Just dough in at around 50-55 with 2:1 ratio and then add 99 degree water and use an immersion heater to heat Sacch. rest.
Dont go over 3.5:1 for the first step because if you may want to raise to higher sacch. rest of up around 68-72 you may need to diluter the mash to around 4:1 ratio.
This will make it easier to mash out by either either hot water or/and immersion heater.
The step up takes about 5-10 minutes depending on the size of mash.

It is not ideal way to get a good filtering from the husks for sparging, moving the mash around so much.
After mash out I leave it for at least 20 minutes and run off really slow the first 5 Litres.

It not ideal step mashing or as good as decoction mashing but a hell of lot faster and the beers still taste fine.

Matti

 

[roger mellie]

Cheers for all the advice Warren/Bindi/matti

I basically gather that in my esky I just have to make porridge - increase temp later.

Hopefully doing a pilsener this weekend - will see how it goes.

RM

 

[Batz]

- makes no difference really - that mash regime is doing the job for screwtop, and I know its effective because its my general mash profile too. All the theorizing in the world about why?? doesn't affect the actual results.

TB

That's the bottom line !

If you don't want to do it don't.

Batz

 

[SpillsMostOfIt]

That's the bottom line !

If you don't want to do it don't.

Batz

But... Sometimes, you just have to do it.

I did not do it today for BIAB batch #60, and the batch I did do it to has spent the afternoon crawling out of its fermenter and all over the fridge. Bad beer, bad!