Batch Sparge Clairity

[Mike Neilson]

Hi there after 10 all grains I am still suffering from sparge Clarity. I mash at 67.8deg for 60 mins, draw my mash till it runs clear, drain the tun then 3 rounds of batch spaging at 74.8deg. stir once, let grains settle then draw till its clear!!!! which is the problem!! it just runs cloudy!! am i doing it wrong? I have resorted to a sparge method which I have no idea that is common practice or not but beer the finished product to my un trained palate seems to taste pretty damn good. My new method is kind of like a fly sparge? Basicly I Mash at 67.8 deg for one hour take my first runnings till it runs clear pour runnigs back into tun, then let it drain half the way down, say 5l then continue to pour my finished pre pre boiled kettle volume on to the grains at 74.8 deg. I dont desturb the grain bed and my run off is clear, my efficiantcy is around 75-80% but my target FG is way off between 4-5points. Why am am I not Hitting my finished gravity? I aerate with a aquiruim pump for 5 mins, as per jmail? and rehydrate as per fermentis instuctions? why is my batch sparge method not runnig clear? any thoughts Lads?

[MrC]

Are you recirculating?

Whan I batch sparge, I recirculate until it runs clear then take my first runnings. Recirculating involves draining some wort and gently adding it back into the mash tun until the runnings are clear (no stirring). I then drain all the wort I can before starting the second batch and repeating the whole recirculating process before draining the second runnings into the kettle.

[Mike Neilson]

Sure am, drawing is my technical term for recirculate, Do you stir you grist? I do am I am starting to think this may be my problem. On Friday i brew a Wit with my Fly batch spargy method, then on saturday I brewed a summer bitter and batch spaged, recirculated the whole 7 litre batch sparge twice and still didnt run clear. Fridays Wit though ran clearer even with wheat in the mash!

[Greig McGill]

Mike, I do it exactly the way you do your new method - temps vary depending on the recipe, but other than that, it's the same. My efficiency is down around 70% though. I usually get good clarity except in low gravity batches (ordinary bitter, mild) where the grain bed is relatively thin and no matter how gently I recirculate, it gets disturbed. I add Irish Moss in the kettle at 5m to flameout, and if I still have issues I add gelatin (1 tsp) when I bulk prime at kegging/bottling time.

As for the pump aeration, nothing to do with clarity, but there was an interesting experiment done here which may interest you: http://media.libsyn.com/media/basicbrewing/AerationMethods.pdf

Your finishing gravity could be related to all sorts of things. Aeration, as you guessed, temperature control (try letting the temperature ramp up a couple of degrees near the end of fermentation if you can), under/over pitching yeast (try mrmalty.com for a good yeast pitch rate calculator - not that I ever use it for dry yeast, bad Greig). Finally, it might just not be done! :) Try letting it sit for 3-4 days after visible fermentation has ceased. Those little yeastie beasties do tend to keep working.

[Adam]

Sounds right your can also extend your mash time to 90 min for a more fermentable wort. eg for my lager like beers a mash at 64-65 with 4L/kg grain for 90min and the beer attenuates very well eg 1.047-1.006. For a full bodied ale I do 2L/kg at 69 for 60 min and get attenuation like 1.047-1.014

[Mike Neilson]

Definitly going to try 66 deg mash to see if that will lower my FG.

[Fairlane]

...or you could just do a starch conversion test with a drop of iodine....