FG v mash temp

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craigite

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The mash temp can be used to design the finish brew, ie dry or sweet. Right?

If yes, what would the adjustment on the FG be?

example
mash at 66deg
OG=1046
FG=1011

What if he mash temp is 62deg?
 
Good question, I know lower temps produce a drier taste, create more fermentable sugars, but does the enzyme effect the OG :hmm:
 
We are talking Alpha & Beta-amylase here, both enzymes work well at a temp of bout 66C, if we mash at higher temp, say 68C then we will produce a more dextrinous beer from the Alpha amylase. Dextrins are unfermentable producing a sweeter beer & a fuller body & mouth feel. If we mash lower say 64C then Beta amylase prevails producing more fermentable sugars & a dryer thiner & more alcoholic beer.
So I woud say if we achieve the same target OG of a given recipe at 2 diferent mash temperatures (ie seperate mash's) then All being equal the lower mash temp will produce, a lower FG & hence a drier stronger beer. wouldnt like to guess how to compensate & adjust for this though :wha: Experience will probably play its part here.
 
surely the FG is dependent on a few things like yeast used temp of ferment and how long you leave it to ferment.
If you use a yeast that likes high alc then you can get a lower FG than one that only likes medium strentgh

horses for courses me thinks
I doubt that the temp of mash would affect the FG as the OG would be different for the same recipie

so do a lower temp mash and take reading for a specific volume
then do the exect same recipie but at ahigher temp mash same volume

I would guesse that the og would be different and that would produce the variable to start with, let alone the yeast type.
 
i was trying to say, if we use exactly the same recipe including yeast used assuming it has a capable attenuation, & including all other factors ie fermentation time/temp etc & arrive at the same OG for both brews,dextrin sugars contribute to the gravity but are unfermentable so the brew mashed at the lower temp will have more fermentables for the same OG so will finish at a lower FG. So will be higher in alcohol & lighter in body
 
Thanks all for the input.
I agree with all points.
Especially the suck it and see :drink: any excuse eh :thumb:

I'm finding that calculations for a brew give a FG of 1011, however with a low mash temp of about 63 the FG measured is 1009. I can exclude the yeast difference as I always use the same yeast.

Just interested to know what others find. :hmm:
 
BrewMarc is indeed correct, although in brewing we talk about the amylase enzyme it is technically the amylase complex, which consists of alpha amylase and beta amylase.

Alpha amylase chops the amylopectin chains into random length chunks (perhaps freeing some maltose in the process) unfortunately it stops when it gets close to 1-6 branches leaving potentially long A Limit dextrins

Beta amylase works from the ends of the amylopectin and long chain dextrins, basically snipping maltose units off the ends of the 1-4 links until it is a unit away from the 1-6 branch and then it has to stop (B Limit dextrins smaller than A Limit dextrins)

Each Enzyme has slightly different temperature optimums Beta Amylase prefers to work around 60-64C and alpha amylase prefers working at around 68-70C, (The amylase complex has a temperature optimum of around 66C to allow for both of these), So if you mash at lower temperatures the wort consists of lots of maltose with mostly malto triose (2 glucose molecules) and malto tetrose (4 glucose molecules) as the dextrins . . . these lighter weight dextrins don't have the body or sweetness of the longer chain dextrins and as there is more maltose the wort is more fermentable. If you mash at higher temperatures then more unfermentable longer chain dextrins are formed (still soluble though so still contribute to OG), and the wort has more body as as more maltose is tied up in the dextrins the wort is not as fermentable, so you end up with a sweeter fuller bodied beer.

As maltose and dextrins contribute to the gravity the OG of a low temperature mash and a high temperature mash will be the same . . . but the final gravity will be different.

That's the theory . . . in practice I've not noticed a massive difference in fermentability until I get to around 68C and then it goes from easily fermentable to not as fermentable.

The Hochkurz mash program makes the most of this by mashing at 62C to get a fermentable wort and then raising the temperature to 70C to get a nice dextrin balance.
 
evanvine said:
Aleman said:
The Hochkurz mash program makes the most of this by mashing at 62C to get a fermentable wort and then raising the temperature to 70C to get a nice dextrin balance.
Do you have any timings for the "Hochkurz" method?
30 Minutes at 62C as a minimum - its used to control the fermentability of the wort, and 40-60 Minutes at 70C . . . certainly until the iodine test is negative . . . and you can extend this to improve head retention :thumb:
 
30 Minutes at 62C as a minimum - its used to control the fermentability of the wort, and 40-60 Minutes at 70C . . . certainly until the iodine test is negative . . . and you can extend this to improve head retention :thumb:



Does this mean if we do a long mash that helps with head retention ?
so if we do a 3 hour mas as per durden park recipies that the beers will by default have good head retention ?
Its not something I have heard before and wonder if thats why no beer i make has any head retention longer than a few seconds, and I allways mash for 90 mins. This definatly seems like worth exploring as soon as I get the mash tun filter sorted out
 
Correct me if im wrong but I thought the Hochkurz Mash was a decoction mash or can it also be applied to a step infusion mash :?:
 
tubthumper said:
Does this mean if we do a long mash that helps with head retention ?

This is interesting ... I've used an overnight mash on my last 3 brews and head retention has definately improved. This could of course be due to other factors, but an interesting point!
 
overnight mash now that sounds really interesting have you done a post I can see of it
also the mashtun really needs to be a good one too
 
Brewmarc said:
Correct me if im wrong but I thought the Hochkurz Mash was a decoction mash or can it also be applied to a step infusion mash :?:
It is a temperature stepped mash program suited to well modified malts . .. how you do the steps is up to you . . . Infusion, HERMS/RIMS, Decoction or Direct heat, choose a method that suits your style of brewing.

I get acceptable head retention anyway so have not noticed an additional effect from extending it . . . often up to 3 hours.
 
tubthumper said:
overnight mash now that sounds really interesting have you done a post I can see of it
also the mashtun really needs to be a good one too

Hi tubthumper
try this http://www.thehomebrewforum.co.uk/viewtopic.php?f=21&t=10160

but there isn't much in the way of pics ... but the tun I use is one of Nicks. The partigyle I did a while back was an overnighter... I'll try and find a link for you
 
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