Benefits for 2 sacch rests?

[Joejkd82]

Looking to brew an exceptionally dry, well attenuated beer with pilsen malt 95% of the grist.

My question: I've seen sone info out there to achieve what I'm after, a rest at 148 for 40 min then one at 158 for 20 min followed by mash out will get me the result I'm after.

I brew on a grainfather, so this is easily achieved.

My question, does this differ at all from a 75 to 90 minute rest at 148?

 

[day_trippr]

From the jump, if you want uber dry, a mash-out is totally counter-productive.
And I'd think milking the beta amylase for all it's worth means keeping the mash temperature religiously below 149°F...

Cheers!

 

[Joejkd82]

Why would a mash out be counter productive? I find I get a good bump in efficiency and it has no impact on fermentability.

 

[day_trippr]

Why would a mash out be counter productive? I find I get a good bump in efficiency and it has no impact on fermentability.

And that's counter-intuitive: a true mash-out is specifically intended to STOP the enzymes dead in their tracks, so how you're getting "better efficiency" from doing it is interesting to say the least.

And if your goal is the dryest result you could get given the recipe, yeast, etc, stopping the enzymes would not make the utmost sense...

Cheers!

 

[doug293cz]

Why would a mash out be counter productive? I find I get a good bump in efficiency and it has no impact on fermentability.

If you're getting better efficiency from a mash out, it's only because your starch to sugar conversion is incomplete at the end of your alloted mash time. The higher temp turbo charges the conversion, but just until the amylase is denatured. You would be better off extending your mash time to improve conversion efficiency, or better yet, crushing finer to get faster conversion.

Brew on

 

[Rcbandl]

The only reason you would get better efficiency from a mashout is you are making the sugars in the mash more soluble from the higher heat.

 

[dmtaylor]

Looking to brew an exceptionally dry, well attenuated beer with pilsen malt 95% of the grist.

My question: I've seen sone info out there to achieve what I'm after, a rest at 148 for 40 min then one at 158 for 20 min followed by mash out will get me the result I'm after.

I brew on a grainfather, so this is easily achieved.

My question, does this differ at all from a 75 to 90 minute rest at 148?

Good question. Answer: Most likely very little if any difference. Personally I would only do the first rest at 148 F for 40 minutes and then runoff, sparge, and heat to the boil. Save a ton of time and effort and get the same excellent results. Note: This response does inherently assume a good fine crush of the grains, and proper mash pH of 5.3-5.5.

 

[doug293cz]

The only reason you would get better efficiency from a mashout is you are making the sugars in the mash more soluble from the higher heat.

This is incorrect. The solubility limit of maltose at 151˚F is 66.7 wt% (66.7˚Plato), which works out to an SG of greater than 1.300. You can't mash thick enough to make a wort above the solubility limit. You also don't need to dissolve any sugar after the mash, since all of the sugar is created in solution. There is never any solid sugar that needs to be dissolved. Any increase in efficiency is from creating more sugar during the "mash out", which can only happen if your starch to sugar conversion is incomplete at the start of the mash out.

Brew on