Hey everyone
I have just found this post by a member of another forum on MO mash temperature:
"heres another thought. mash @150 and use a yeast with high attenuation = dry
mash @ 156 with a low attenuation yeast = full mouth and sweet
mash @ 156 with a high attenuation yeast = full mouth and only slighly sweet
mash @ 158 with a high attenuation yeast = full mouth, nice malt and slightly sweet.
I would mash 158 for 90 with a 1.5qts /lb ratio (an entire discussion on its own, higher qts/lb = longer time but better conversion) and use a high attenuation yeast like 1056."
I'd like to know if you guys agree on the 1.5lbs/qt and 90 minutes mashing at 156-158 F.
The reason why I am asking is simple: I'd like a nice, full mouth and only slightly beer.
Thanks for the replies in advance.
That's not
quite accurate. Above 156 F, beta amylase - the enzyme that produces the majority of your fermentable sugars - starts quickly becoming denatured (in other words, it stops working well then quits when the mash temp gets even higher). Alpha amylase - which produces
mostly unfermentable sugars - works better at higher mash temperatures, which is why you get a fuller body and mouthfeel. Alpha
will produce some fermentable sugars, but not nearly as quickly or efficiently as beta (credit to Kai Troester for his excellent wiki: braukaiser.com).
If you're doing a single-infusion, single-temperature mash without temperature rests for the individual enzymes, then your mash thickness can play a greater role in your wort production than if you did a step mash alone. The reason for this is that in a thinner mash, enzymes are more active and can do their work faster than they can in a thick mash. Your grist crush also factors in here as a finer crush exposes more of the endosperm's surface area and lets the enzymes work more efficiently. Therefore, you can have full starch conversion in very little time (perhaps on the order of single-digit minutes) if conditions are right. So a thinner mash does not mean "longer time but better conversion". It's not quite that simple.
Your mash pH can also affect conversion time and efficiency. Too far outside of their preferred range and the enzymes will take longer to convert than they do when in their optimal range (a good middle ground for both is around 5.2 pH at mash temperatures. 5.5 at room.)
So basically, if you mash at 156-158 for 90 minutes, you're going to get a wort that has full body and mouthfeel, and you will get more fermentable sugars than if you just mashed for say 60 minutes since alpha amylase will continue to produce fermentable sugars. It just takes longer (and beta amylase will still be at work at those temperatures producing fermentable sugars, it just won't be nearly as active).
You could step mash and give the beta amylase a rest at a low temperature for a few minutes (to ensure you get the fermentable sugars you're after), followed by a higher temperature rest for alpha which will give you the mouthfeel and body you want (and I'd follow that with a mash out to stop conversion). All things being equal, doing this can be done faster than just a single-temperature, 90-minute mash.
I personally mash around 1.75 - 2.0 qt/lb for 30-45 minutes and never have efficiency problems.
This recent thread (click) was on some of the same topics. He mashed at 156 F for 45 minutes, and was surprised that he only converted 88% of the starches to sugar (you really should get almost 95% of your starches converted to both fermentable and unfermentable sugars every time). So that made his SG/OG lower than expected.
You should check out this page:
http://braukaiser.com/wiki/index.ph...ity_and_efficiency_in_single_infusion_mashing
And this one too:
http://braukaiser.com/wiki/index.php?title=The_Theory_of_Mashing
