[daze1231]

Hi Y'all-

I've noticed some recent batches have what i perceive to be an astringent quality to it, and i'm analyzing my processes to pinpoint the reason.

I mash using a 10-gallon Rubbermaid cooler with a false bottom. Almost in 75% of batches, the mash gets stuck, and i usually have to transfer the mash to another vessel, clear the clog, and transfer again, and begin the lautering process over.

During the process, the grains get agitated quite significantly and it's very time consuming when it happens. So, i'm wondering whether these two factors may contribute to the astringency, as the agitation of grain may be extracting tanins from the husks, as well as a rising PH due to the additional time the grains are in the mash tun.

Any light that can be shed on this by anyone would be most appreciated, and suggestion certainly welcome..

Happy Brewing!


-DAZE

[diybrewing]

Why are you getting such a high number of stuck mashes? 75% is really a high percentage. I have had 1 stuck mash in the past 6 years.Did you make your own false bottom? Have you ever tried rice hulls?
Your astringency could be coming from the amount of transfering you are doing, Are you checking the pH at any time during this time?

[daze1231]

i guess my false bottom sucks, is my best guess. or maybe its i try to brew too big of beers for my mash tun. i also started to do a regular mash out, which seems to have helped.

Have not done any PH testing as of yet, but that's certainly good advice.

Thanks!


-DAZE

[gail]

Are you using a plastic false bottom or a stainless one?  The only stuck mash I've ever had in 9 years was with a plastic false bottom that floated on me, causing a clog in the valve.
Gail

[daze1231]

it's a stainless one, but i notice alot of grain somehow manages to slip underneath it and get sucked into the drain valve. maybe it's too small in diameter for my mash tun, but it was the one that came with the kit from northern brewer.

-DAZE

[gail]

Possibly try making sure you're not dislodging the false bottom as you stir, causing grains to get underneath.  A smaller amount under the false bottom will just run out of the valve as you recirculate until the grain bed sets.
I'm wondering about your crush--too fine will create stuck mashes and may also lead to excessive tannins in the finished beer which might seem astringent.  Astringency will feel like chewing on grape skins, or even like drinking strong tea, sort of drying on the sides of your cheeks.  How much flour do you have in the grain after milling?
Gail

[daze1231]

i have my grains milled at my LHBS, and that doesn't seem to be the problem. I think you might have nailed it with the question about my stirring.... i'm probably inadvertently lifting the false bottom up slightly through aggressive stirring, therefore allowing grains to slip under the false bottom..

Thanks again for the advice!!!!

-DAZE

[gail]

I think I use the same stainless false bottom (from my LHBS tho, not NB) and it really works great, no complaints.  Hope that changing your stirring ends your hassles of stuck sparges AND the astringency you're sensing.
Good luck,
Gail

[daze1231]

so glad i joined this forum..this place rocks!

-DAZE

[denny]

as well as a rising PH due to the additional time the grains are in the mash tun.

I'm curious about this statement.  I don't think I've ever sen any correlation between a longer mash and rising pH.  Anybody else?

[daze1231]

perhaps i'm mistaken here Denny. Sounds like if there was a correlation, you'd know better than I. I think i menat that a longer mash would create a situation where more tannins would be extracted, which sounds like has nothing to do with PH.

Thanks,

-DAZE

[denny]

I think i menat that a longer mash would create a situation where more tannins would be extracted, which sounds like has nothing to do with PH.

I've heard people postulate that, but IME I've never had it happen.  I know that a lot of people who do overnight mashes and have never reported this happening.  I tend to think it's more theoretical than real.

[gail]

Sounds like a few different things are being discussed here.
Correlation between astringency, tannin extraction and pH--yes.
Correlation between length of mash and pH (with the exception of an acid mash)--not that I've ever heard, read about or experienced. 
Anyone know of any data to correlate length of mash (after the initial 10-15 minutes or so at sacc temps) with rising (or even changing) pH?  Kai?
Gail

[denny]

FWIW, Gail, it's something I've often heard repeated but I don't think I've ever seen any data about it.

[gail]

Denny...this has my curiousity going.  What would make this process happen (rising pH in longer mash)?  Once buffered, how would this change?  What chemical changes are being produced in very, very long mashes?
Gail