Deliberately Mashing Above 70c

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buttersd70

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In my quest for a medium to full bodied, low alcohol beer, using yeast of choice, rather than depending on low attenuator, I have been doing a bit of research into the theory of mashing, particularly in relation to the creation of dextrins relating to mash pH, and more specifically, temperature.

Does anyone here have any experience in mashing (deliberately) above the "usual" sacchirification temperature range of 60-70, in order to deliberately produce a less fermentable wort? or with doing either a stepped or a blended mash, with the main sacchirification temperatures being such that beta amalyse is denatured, either from the outset, or early, in order to give full weight to the alph amalyse side of the conversion for the same effect?
 
Going above 70 will work but you have to look at the mash as a balance. 66C is often quoted as the good average as it is within the gelatinisation range for malted barley starches, is not to high so as to denature the beta amylase too quickly and is at at a good temp for alpha amylase. Now, beta amylase does not just cark it like a light switching off, it degrades according to temperature, even at 75C it will still have a half life of at least 5 minutes.
What else is likely to happen though is that may get more tannins than you bargained for and the dextrinous wort you produce may be too dextrinous.
My suggestion is to use as much grain for the LA beer as you would for full strength, mash at 68-70 and blooger all sparge. Add the water you would have sparged to get your volume direct to the kettle. This way you are pulling the big malty components out and avoiding tannin problems. I am drinking an Oktoberfest and a Maibock at the moment (not at the same time ), both have a big malt finish, both attenuated quite well and both were made from the same mash with blooger all sparging (50% efficiency), the Okfest was diluted to gravity in the fermentor.

K
 
Thanks doc, an interesting take on the issue.

For what I am trying to do, a surplus of dextrins is actually the least of my problems, because regardless of how I go about it, I would be doing a fast ferment test to check the attenuation, and hopping accordingly to compensate.

The issue with the tannins is interesting, though. Would tannin extraction really be an issue at around the 72C mark? Particularly if care is taken so that the mash pH is not too low? say around 5.6 ish?
 
In my quest for a medium to full bodied, low alcohol beer, using yeast of choice, rather than depending on low attenuator, I have been doing a bit of research into the theory of mashing, particularly in relation to the creation of dextrins relating to mash pH, and more specifically, temperature.

Does anyone here have any experience in mashing (deliberately) above the "usual" sacchirification temperature range of 60-70, in order to deliberately produce a less fermentable wort? or with doing either a stepped or a blended mash, with the main sacchirification temperatures being such that beta amalyse is denatured, either from the outset, or early, in order to give full weight to the alph amalyse side of the conversion for the same effect?
What yeast are you using? I find Wyeast 1968 with a 69degree mash works well for giving a reasonable amount of body
 
butters,do you make all your beers below optimum gravity?

You seem too,and you also seem to try and keep the balance correct.I understand for English milds ect,but do you enjoy a nice trippel?

Respect for your process.

I'm nosy why?
 
No, not all are below 'optimum' gravity. English Mild is my favourite drop, I must say, followed by best bitter. But I do enjoy a stronger drink as well. Actually, my last 3 have all been 1042-1050 OG, and when I get around to it I will be experimenting a bit more with still higher gravity, possibly belgians, or even a barley wine.

For me, balance is the key, as you say....

As to the why. My usual Mild is my favourite session, it has an ABV in the region of 3.5%, and is mildly hopped, and is a good session beer. But I want to go lower in alcohol, if possible, without sacrificing flavour or body. I dirink most when I'm with my friends, having a drink and shooting the proverbial. And I find that a better time is had if you can still stand after throwing 10 pints down my neck. ;) But the quality has to be there. I've done a few table beers, but table beers in general aren't normally really anything to write home about.

Ausdb, agree that 1968 would help. I'm using 1275, which attenuates higher. But even with the lower attenuating 1968, you still have these issues, particularly when moving into the sub 1030 OG range, which is what I am attempting.
 
Could not agree more re the quality you are seeking,I'm glad i am not trying to replicate styles you seek with half the gravity.

Like I said respect to you,it must be a nightmare crunching numbers and trying to keep the balance "out of style"

Regards hoohaa
 
I did a tasy NZ light/mild beer that finished at 1014 from an OG of 1036 for 61% attenuation. Mashed at 69 and fermented with windsor dry yeast at 18.

I guess its just a question of how much body you want left behind. I like my beers in the 1012 to 1016 range, so this was nice. It may also have had something to do with no bittering additions and 100g of fresh NZ hops added over 15 mins in 21L :icon_drool2:
 
Dave
My Milds have similar og/fg to what you are getting, I also mash these at 69. My Mild recipe is sorted, and has been for some time. But what I am trying to do now is a low alc, under 2%, starting with a much lower OG, and still end at around 1012 ish. Which would mean a starting grav of 1025-1027, but with only 52% apparant attenuation. For this project (or folly ;) ), I've set myself the limiting paramaters of under 2%, with FG>1010.
 
Works for me.

Start your mash at 70*C and see how much attenuation you get with the fermentation. Should be all you need. Keep the normal brewing process along with the higher mash.

Using this mash with the right yeast will give you less attenuation and a fuller, higher final gravity.
 
I tried an experimental beer that a couple of under grads had developed at Ballarat Uni last year as part of their course that was based exactly on this theory. It was 2.5% ish and from memory they mashed at 73c - it was a delicious drop and you NEVER would have guessed that the alcohol was that low. It was fairly dark, colour of a dark mild I guess or almost porterish.

I reckon a hefty dose of darker malts is a good idea to help balance a low attenuator.

Cheers
 
Sounds to me like a Jump Mash would be ideal for what you are trying to achieve.

This process optimises alpha amylase activity, while jumping over the range where the beta amylase is active, the resulting beer only has an attenuation limit of around 40%.

A thick mash is made at 35 C (say 1.5:1) and held at this temperature for 20-30 minutes.
Boiling water is then added to the now well hydrated mash to bring the temperature up to 72 C.

Its a two person job; that mash is very stiff and you want to get the water in and mixed pretty sharpish, without missing the temperature. The process is best suited for mechanically mixing.

For home brewers its best arm your self with a very good mash paddle or find a mate who is an experienced Kayaker.

Hope that helps

MHB
 
like that "jump mash" idea, might give it a go for fun one of these days.

Another way to do it could be to look at malt choice in combination with a higher mash temperature. I get a lot of my base malt from work, this stuff is predominantly schooner malt and its designed for big breweries who use a lot of sugar adjunct. So it produces a quite dextrinous wort. I usually run a step mash routine to make sure I get a dry enough beer, you would be looking for the opposite.

Its also quite temperature stable and retains enzyme activity at higher temps than most malts.

The other thing to consider is judicious use of adjuncts. You are talking english beers here, so adjunct usage fits within the traditional scheme. And you are talking about doing a forced fermentation to find you limit of ferm. You could aim for a "really" dextrinous wort - go the whole hog, do the jump mash from MHB, miss a big chunk of the sparge as per DrK and use a dextrinous malt a I suggested.

Make it thick, malty and syrupy - then on brewday, No-Chill the bulk of the wort leaving out a litre or two for a fast ferment. Force ferment it and then use the results to work out how much water to add to get the body you want, then if needed, bump the OG back up with a sugar adjunct that will not add to the body of the beer. A few litres of extra wort will give you a chance to do a couple of experiements to really dial the beer into the zone before you scale it up to your main wort.

More or less take what you are trying to do "too far" then scale back

Might work???

Thirsty
 
Thanks guys, big help, particularly MHB. Sounds like I will be going with the jump mash, and will probably also hold back on some of the sparge water as well. Followed up with an fft, and take it from there.

If worst comes to worst and it attenuates too far, and becomes a bit watery, all is not lost anyway, I've planned for that eventuality. The flavour profile will not be dissimilar to my regular mild, so worst case is I'll do a stronger and heavier mild than usual, and blend the buggers ;)

Cheers, guys.
 
So, an update. I gave the jump mash a go. And here are the results.

What I thought would be the hardest part actually turned out to be the easiest, and that was the doughing in, at 1.6L/kg. Mixed up nice and easy, and got a reasonably homogenous 37C. I presume it's to do with it being below gelatinisation temp that made the mixing not too hard?

The next part is where I ran into issues.....calculated the volume required to raise to 72C with boiing water, and, realising that I would get temp losses just on running in, upped the volume a bit. (so basically beersmith told me I needed 95C water). I got it rolling, then cut the power and ran it in....stirred,....and the temp was under 70. Bugger. Ran the rest of the water in, and got it to 70C, but at this point I had ran out of water. I had decided to go with a double batch, with a mashout, which would fill the esky and allow 30L runnings with no sparge.That was my mistake, given my equipment limitations. Should have gone with a single batch.

So, I left it at 70C until iodine test was OK. Ran it out, and had hit the 70% efficiency I had calculated. I could have either got more water on at the start of the mash, and sparged, increasing the gravity. Or reduced the final volume, increasing the gravity. Or I could go ahead as planned, and see how low it would attenuate. I decided to take the 3rd option, knowing I would likely get a beer lower in body than what I was after, but allowing me to have data to work on that hadn't been 'fiddled in the middle'. I figured that in the interest of future trials, that would be better....

So, 30L ran out, boiled, hopped, and NC. When cool, checked level, and OG, split evenly between 2 fermenters, and topped with water, ending up with 2 x22L 1025 worts. The hope initially was to have 45% attenuation, ending on 1014, and I hopped at 95%BV with this in mind (knowing that if it attenuated further, the hopping would not be too bitter.) It ended up just under 1010, so about 60-64% Attenuation. (with 1275, thats not a bad drop in fermentability).

Force carbed the first one last night, whilst the second one is getting a bit more time in a cool cube. Whilst it hasn't dropped bright yet, It's a very easy drinker. Not what I'm after, which is a 2% that you can't tell is 2%, but better than any other 2%ABV beer I've had. To put it into perspective, I think 90% of AG brewers would consider it lacking in body (but would probably still be surprised at just how low it is, and I reckon over half would finish the glass anyway.), but 99% of kit brewers would consider it heaven, and extract brewers would probably be equally split.....I'm still considering what to do with the second batch, I will probably blend it. Maybe. But maybe not. It's not bad, just not what I was after, and hot weather is coming....

So, the experiment will continue......
Take 2 will have additional 'strong' malts in it. I'll up the caraaroma from 6% to 10-15%, which normally would be a bit of overkill, but in this, I think will work. It will be a single batch, so I have more control available. I will make sure I have ample water available to hit temperature, and might mash in a pot instead of in my esky, so that if it is under, I can quickly heat it for the extra couple of degrees. And I might push the OG a couple of points higher.

Mind you, in my typical fashion, I'm making things as hard for myself as possible.....because I'm trying to do what is essentially a Mild, which is more malt driven anyway, and thereby exagerating any lack of malt in there. If I was passing it off as an American, the lack of malt wouldn't be as out of place. ;) . Actually, thinking about it, the body and malt flavour in there at the moment is not dissimilar to a golden ale. Can't be too bad, I've just knocked back 3 pints whilst typing.

But at the moment, I need to get more of my usual brews on, as stocks are low....but I will revisit this, for sure.
 

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