72 replies to this topic

[BlKtRe]

Interesting. I'll mash Alts, and a lot of others at 148df. Usually I've started recirculating with the EHERMS about 20 - 30 minutes into the mash. Around 50 minutes I'll reset the Ranco to about 167 for mashout/extra solubility. Guess I do have a short alpha range at the end. I don't really know how much is left for alpha to take care of at that point that beta hasn't chopped away at already.

Thats what I was kinda thinking. Most breweries start sparging as soon as they mash in. I spoke with Steve at Freestate and they get conversion in 20 min. 23rd also sparges within or before that time frame as well.

Edited by BlKtRe, 04 January 2012 - 05:25 PM.

[djinkc]

Thats what I was kinda thinking. Most breweries start sparging as soon as they mash in. I spoke with Steve at Freestate and they get conversion in 20 min. 23rd also sparges within or before that time frame as well.

No doubt, but the sugar profile can change after a positive iodine check. That's what my question is, can you expect significant alpha amylase activity after 20 - 30 minutes in the beta range. Guess I need to hit the books again.

[Brauer]

maybe I'll give that a shot next time around. so you mash a little thick to begin with and then infuse some boiling water to raise the temp?

The last one I mashed in around 1.5 qt/# then used boiling water to bump it up to around 2 qt/#. I follow a schedule similar to Cavman, I go 30-45 min at 148°F then 20-45' at 158°F+. In addition to what DJ said, there was a decent article in BYO recently and a number of independent experiments that have shown that there is often 10-20% starch left to convert even after a 60' mash, often despite a negative iodine test. This is even more apt to be the case if the mash starts below 150°F, since this appears to be due to the mash being below the optimum temperature for gelatinization. Perhaps its the coarser grits require an extended mash or elevated temperature to fully convert. That's probably one of the reasons so many brewers see mash efficiencies around 70-75% when the predicted efficiency of a batch sparge of a moderate gravity beer would be closer to 85-90%.

[djinkc]

The last one I mashed in around 1.5 qt/# then used boiling water to bump it up to around 2 qt/#. I follow a schedule similar to Cavman, I go 30-45 min at 148°F then 20-45' at 158°F+. In addition to what DJ said, there was a decent article in BYO recently and a number of independent experiments that have shown that there is often 10-20% starch left to convert even after a 60' mash, often despite a negative iodine test. This is even more apt to be the case if the mash starts below 150°F, since this appears to be due to the mash being below the optimum temperature for gelatinization. Perhaps its the coarser grits require an extended mash or elevated temperature to fully convert. That's probably one of the reasons so many brewers see mash efficiencies around 70-75% when the predicted efficiency of a batch sparge of a moderate gravity beer would be closer to 85-90%.

I get pretty good efficiency out of the tun. After that it sucks. I should note that I crush mine pretty fine. Last time I checked the mill was at .029. Maybe that's why I hit good numbers even though most of the mash is really not at ideal temps to gelatinize.

[BlKtRe]

I used to mashout via HERMS starting at 40-45 min. into the mash. I now just add 170* sparge water after 60 min. then turn the heat on in the kettle when I collect a little more than 1/3 of my preboil volume. Wonder how this effects the 10-20% of that starch. And something else, would 10-20% really effect the final outcome?

[Brauer]

I almost never mashout, either. If you are sparging with 170°F water, the gradual temperature rise of the grain bed and the wort probably go through the equivalent of a short alpha rest, I'd think.On my system, running the math with a head cold, 10-20% additional conversion on a 1048 beer is the difference between 88% or 80%-72% efficiency. That would mean that at least 8-16% of the sugar would have been converted at an alpha rest. I think that means that the sugar from the alpha rest of that starch would have to be ~40-60% unfermentable to bump the FG by ~2 points, I think. That seems like it would be an easily noticeable change, if it was actually that unfermentable, but less might be enough to come across as a satisfyingly subtle increase in body and you would need less if you started the alpha rest earlier.Kai Troester did a mash temperature experiment on Pilsner Malt, followed by a fast ferment test for the upper limit of fementability from that wort. He measured a maximum fermentability of ~87-90% at 145 & 151°F and 60% at 167°F. Too bad he didn't test 148°F. I can't find if this is apparent or real attenuation, at the moment. (By the way, he found that attenuation decreased by ~4% for every 1°C, or ~2% for 1°F, increase in mash temperature above 151°F, in a very linear fashion.)That seems like a 40-60% unfermentable wort at 158-162°F might be a stretch, if you are depending on all the additional unfermentablity coming from just that bump in conversion, not some conversion that would have been completed at the lower mash temperature finishing at the higher temperature.Frankly, I just use this technique because it was the first one that gave me the results I was looking for, which was a dry tasting beer that wasn't lacking in body. When I started just raising the mash temperature in a single infusiion, my beer seemed to be getting a more cloying sweetness. When I tried a beta-alpha step mash, I got a dry tasting beer that had a nice body. There are so many variables in this process, and I've had other brewer's beers that were mashed warm that weren't sweet, that I think there are more than one ways to get the same result. This was just the first one I stumbled upon that worked in my brewery.

[positiveContact]

The last one I mashed in around 1.5 qt/# then used boiling water to bump it up to around 2 qt/#. I follow a schedule similar to Cavman, I go 30-45 min at 148°F then 20-45' at 158°F+. In addition to what DJ said, there was a decent article in BYO recently and a number of independent experiments that have shown that there is often 10-20% starch left to convert even after a 60' mash, often despite a negative iodine test. This is even more apt to be the case if the mash starts below 150°F, since this appears to be due to the mash being below the optimum temperature for gelatinization. Perhaps its the coarser grits require an extended mash or elevated temperature to fully convert. That's probably one of the reasons so many brewers see mash efficiencies around 70-75% when the predicted efficiency of a batch sparge of a moderate gravity beer would be closer to 85-90%.

what would happen if I did the step mash as you are describing and then left the mash overnight? I do pretty much all of my mashes overnight now and I don't think it has had a great affect on the final product but I could be wrong.

[Brauer]

what would happen if I did the step mash as you are describing and then left the mash overnight?

Never tried it. I'd assume that the beta amylase would denature while the alpha amylase wouldn't break the complex sugars down and then they would eventually denature. I suppose it might lose a little body if there were a few stubborn beta amylase molecules that hung around for a while and kept slowly chewing away. I think I'd probably raise it to mashout temperature, if I ever tried an overnight mash, but you have a lot more experience with them than I do. Let me know how it works out if you try it.

[positiveContact]

just an update - this is a nice beer. it has a ton of malt aroma - my wife described it as beer candy as it enters your mouth. this is despite the very low FG. I think it will take another month or so for it to really hit it's stride.

[BlKtRe]

just an update - this is a nice beer. it has a ton of malt aroma - my wife described it as beer candy as it enters your mouth. this is despite the very low FG. I think it will take another month or so for it to really hit it's stride.

Now to start playing with NG and Dussie Alts to see which you like better.

[positiveContact]

i can't remember which is which but I seem to remember one looked more up my ally - i'm not sure which I've brewed here...

[denny]

Wyeast suggests 55-68° F

I have a btach going now that I pitched at 48 and is blowing off at 52.

[djinkc]

I have a btach going now that I pitched at 48 and is blowing off at 52.

Cleaned up a 1007 mess earlier today that overflowed the blowoff bucket......