Conversion Time

[MrBIP]

Made my third all grain batch yesterday (recipe link below).
I did a protein rest for 20 minutes and then raised the temp with boiling water for conversion 60 minutes.
Used Palmers book to calculate volume and temps for water, hit everything (within a degree) as planned.
But, after 60 minutes, I could tell, before I even confirmed with iodine, that conversion was not complete.
It ended up taking another 40 minutes, I had to add a bit more water to get the temp back up for the last 20.
In the end it seems to have all worked, OG was higher than planned, 75% efficient vs the 65% I originally put in the recipe, and it's bubbling away this morning, but I'm wondering now about the conversion time. In Google searching last night and again this morning, I find all kinds of general discussion/articles about how the mash works, step mashing, mast temps, checking for conversion, etc., but nothing specific about calculating or predicting the time. So, I'm left wondering, my first two batches (a pale ale and a california common, 2-row with a bit of crystal and speciality malts), 60 minutes, bingo; this one didn't get there. Why?


(I updated this last night based on the actual experience of the first go... the updates are noted at the bottom)
http://www.brewersfriend.com/homebrew/r ... l-invictus

 

[grainy one]

had the same problems with mash last month. the American - White Wheat needs a longer mash time.
I plan to soak the American - White Wheat at @125 for 20 min before adding it to the main mash next time. I'm thinking this may work ok. doing this will allow me to keep my main mash temp , with out adding boiling water to it. I like to keep the grist/water ratio even throughout the mash.

 

[Ozarks Mountain Brewery]

the people with advanced systems that you read on the forums don't really go into detail about their times and set ups except to say 60 minute mash rest, I will say that allot Ive herd from use the rest for 60 then fly sparge for 60 method meaning recirculate over the top just to be sure on any beer, which means 2 hours total mash time.

I my self some times skip the first rest and do the recirculate for 60 only, what that does is evens out the temperature consistently throughout the mash tun and that is a problem for some that just do a rest, the mash tun temperature might be inconsistent and not getting enough water penetration in some areas and leaves you with a lower efficiency

there's the dryer the grain the longer the mash too.

 

[Nosybear]

Sounds like a lot of trouble, sparging for 60 minutes. I run the wort until it's clear, adding it back (recirculating), then run it into the pot. Usually I recirculate about 2.5 gal for 7.5 gal runnings. My conversion time is generally less than 60 minutes in my Igloo mash tun: I try to hit just above mash temp, let the temperature fall for the first 30 minutes, re-temper and let the temperature fall through the rest of the mash. I stir and monitor the temperature every 15 minutes. The 60 minute mash time is overkill - generally 30-45 minutes are enough - but the engineer in me knows it will ensure conversion over 95% of the time (but not 100%). The brewer in me knows that lots of wheat, adjuncts or cool mashing can increase the required conversion time. So when I'm mashing cool or using a lot of wheat, I do conversion tests, if I remember to do so. Once you've done about ten or so batches, you begin to know what a well-converted wort looks and smells like and react to that. In fact, I'm going to start testing at 45 minutes - fifteen minutes of a brew day back is pretty substantial!

 

[Ozarks Mountain Brewery]

I admit I have pumps, hoses, a hopback and false bottoms, screens, temperature pid's, whole thing is automated.
but yes stirring and monitoring every 15 to 30 is crucial

 

[MrBIP]

Sounds like-
1) Longer time likely necessary for wheat.
2) Mash started at 154 and this cooler has held heat well, but I was multi-tasking (went out to snow blow the driveway during the 60 minutes), probably better stay on point next time out and watch closer. It did drop to 151 at the end of 60.

I see what you mean by at least the appearance of of the wort Nosybear. As soon as cracked the spigot and let some run into that bowl I knew it. It was not clear/"shiny", it was milky looking and dull. Once I screwed around for the extra 40 minutes, it was also apparent that I had gotten there.

So it seems with all the varieties of brew systems, malts and various combinations of things, it wouldn't be realistic to expect a calculator to target a specific time, but with all the detailed calculations available for pretty much everything (and accuracy of those things), I'm surprised not find one. Just have to leave it to the "art" part of homebrewing I guess.

The other option that was mentioned here was to do the protien rest away from the main mash and then add it all together and do one infusion. I actually considered doing that and after walking through this, would probably do it that way next time.

Thanks for the feedback on that one.

 

[surfmase]

Thought I'd piggy back onto this thread with another conversion time question.

When using multiple rests in a recirculating wort setup, how long does everybody need to ramp up to the next rest? Has anyone seen a graphic of temp vs time? I recirculate the wort with HERMS setup to do multi rest mashes. It takes about 30 minutes to raise from 50C to 63C and another 20 min to raise to 72C. By the time I get there I hardly feel like resting 30 min...

Anyone have notes on how long it took to raise temp from rest to rest?