Mash efficiency down - position of hose or temp?

[norstar]

Hi all. I've done another brew today to reuse my yeast and I've used Tesco Ashbeck spring water. No issues with pH today, that's for sure.

My mash efficiency is still poor though (only 65% - I used to get better when I first started), and I think I've narrowed it down to two things:

1) My sparge water started at approx 77 degrees and will have dropped slightly as I went along. Is this too cool? The grain bed was at 65 degrees upwards throughout.

2) The braided steel hose I use to filter the wort in my coolbox mash tun is quite long and coils around. It turned out it was "up" in the grain bed rather than laying flat on the bottom, so presumably I'd be losing some efficiency to liquid only going through some grain and then into the hose and out rather than down into a false bottom space and out?

My mash tun is a thermos coolbox with a tap at the bottom connected to a three foot length of braided stainless steel hose. I mash with 2.5l/kg and then run off water to keep the grain bed from drying using a pierced foil strip over the top to distribute it.

Is either one of these likely to be the culprit and any idea to what extent? Would batch sparging sort this out instead as it's all immersed at once?

[NobbyIPA]

your methods sound fine to me

only thing you don't mention is the speed you sparge at

i never exceed 1 litre in 1 litre out per minute
mash over 90 mins at leaste

fully heat the mash tun and tap etc prior to mashing?
i have the same tun but have a 22mm copper manifold


i get around 75 - 80% according to beer smith

[Ren]

I had some efficiency proplems before. I try to mash thinner 3l/kg which results in better conversion.
Have you checked your thermometer?

[norstar]

Yes, thermometer is A-ok. The thing is, that manifold is great and would sit at the bottom, so any water would have to seep down through all the grain before reaching it - presumably taking all the sugars with it. With mine, the flexible hose sometimes springs up and I found yesterday that it was only about an inch or two below the top of the grain bed, then spiralling down to the bottom.

Temp was 65 degrees and held, and it took me half an hour to sparge and collect 20L.

I read an article suggesting that the grain bed should be 76 degrees when sparging, hence the need for hot sparge water, but the bed was only mid 60s when I checked it yesterday. Could that impact efficicency by 10%?

[cumbrianwolf]

Many factors contribute to a low extraction rate, such as the coarseness of the grain when milled and the mash adjuncts absorbing some of the malt sugars. I sparge with water at 80oC and this is due to thermal losses on the path down the syphon tube and then onto the copper sparging arm.
How are you testing the end of sparge are you merely tasting it or using an instrument such as a refractometer?
If your tasting it by mouth you can miss out on at least 10-15+ degrees of specific gravity.

[Padalac]

hummm.. you could try doing everything the same except do a batch sparge, if your efficiency improves then its probably a problem with how you were sparging.

[norstar]

I test the last runnings with a pH strip and also Hydrometer, suitably cooled of course. Problem is, I collect what my recipe tells me and unless I'm really stretching it, never get near 1.008 or lower to risk tannins etc.

I'll try a batch sparge I think. The other factors all seem very consistent but I have a feeling that what's happening is that with the fly sparging, the liquid is passing through the top 2-3" of grain, into the section of braided hose and then it's simply following the hose down and out, without really passing through the entire grain bed. I'll also try increasing my sparge temp to 80 degrees +.

[Padalac]

I've always had high efficiencies with batch sparging, and I'm not doing anything sophisticated at all. I find it easier that way, but it seems to give 80% + efficiency.

[norstar]

How do you do it exactly? 2.5l per kg at 65sh, then two lots of 20min mashes at 80?

[guypettigrew]

The sparge liquor needs to pass all the way through the grain before running out. If your liquor isn't, then you'll probably only be collecting the sugars from some of the grain.

Have you got a picture of how your braided hose fits into the mash tun, please? The usual place for a grain filter is on the very bottom of the tun, with slots (if it is a slotted type) pointing downwards to maximise the amount of sparged wort which can be collected.

Guy

I test the last runnings with a pH strip and also Hydrometer, suitably cooled of course. Problem is, I collect what my recipe tells me and unless I'm really stretching it, never get near 1.008 or lower to risk tannins etc.

I'll try a batch sparge I think. The other factors all seem very consistent but I have a feeling that what's happening is that with the fly sparging, the liquid is passing through the top 2-3" of grain, into the section of braided hose and then it's simply following the hose down and out, without really passing through the entire grain bed. I'll also try increasing my sparge temp to 80 degrees +.

[Padalac]

How do you do it exactly? 2.5l per kg at 65sh, then two lots of 20min mashes at 80?

yea, i'm using the 45l igloo mash tun, with a braided hose filter. this one:
http://www.ebay.co.uk/itm/Deluxe-Insula ... 27ec6985aa

I just follow the mashing instructions from beer smith.. usually I am starting with 4-6kg of grain and 11-15l of water - temp 64-69c depending on recipe. i currently adjust ph with CRS by trial and error with ph strips but this is insanely shit so i am gna try and switch to using 5.2 buffer from 5 star.. then I top up with sparge water at a higher temp (78c and ph-adjusted with CRS), stir and leave 10 mins, then drain until i reach my required pre-boil volume. as i said, nothing sophisticated, but i often overshoot my recipe efficiency assumed at 75% and end-up liquoring down.

in terms of procedure..
-I pour in the hot liquor into the mash tun
-dough in fairly slowly, stirring as i go to get an even mix with no lumps or hidden dry balls
-check temp is correct, adjust if necessary
-then check ph, add crs, check again and readjust, and check until correct..
-recheck temp
-then i leave it for 60 mins
-i used to stir, but i dont bother any more, i just leave it to rest
-then do an iodine conversion test

-take runnings quite slowly until the tun runs dry

-refill with sparge water at 78c, stir and leave 10 mins

-take second runnings as slowly as possible until i reach pre-boil volume.

[Mr. Dripping]

I would definitely try a batch sparge next time.
At least that way you can eliminate any issues pertaining to channelling or speed of run off.
From what you describe, I would lean towards the problem being a channelling issue......particularly if some of the braided hose is sitting high in the tun.

[Jonnyconga]

I agree with what a few have said in terms of if the braided hose sits high then the water will take the path of least resistance and once it's in the hose it ain't coming back out. I have a very simple copper manifold I made in the bottom of a rectangle Coolbox and normally get eff of 80%+. That's only if I sparge enough though - I under sparged once (without realising) and my eff dropped right down.
I tend to add sparge water at 80deg I'm batches until the volume in my brew pot is what I'm after. I get varying effs due to this I guess.
Sort that hose out!

[paulg]

reading the above it sounds like you are already batch sparging not fly sparging as you state you

-take runnings quite slowly until the tun runs dry
-refill with sparge water at 78c, stir and leave 10 mins

when I was 3 vessel brewing I batch sparged and always has a 80-85% efficiency .I was using a copper manifold similar to the one shown above.I agree with the reasoning about the braided manifold being high in the mash and would consider making a copper manifold .It is easy ,you only need a hacksaw and a couple of metres of pipe and 5 bends and 3 tee pieces

good luck

[norstar]

Thanks for all the replies above. I tried to put a false bottom in to the thermos coolbox to "hold the hose down" but at the moment, I can't find anything that doesn't float up!

So I did a brew tonight using batch sparging for the first time. I mashed with 2.5l/kg for 60mins (short of time tonight), topped up to 18.5l after that, stirred & let sit for a minute, recycled 4-5 times, ran off quickly into a boiler and then refilled with another 18.5l at 80 degrees. Stirred and left that for five/ten mins then recycled 4-5 times, then ran off fairly quickly.

Ended up hitting 75% efficiency which is probably ok for a 60min mash, and hit my targets bang on so I think I'll stick to this until I can make a false bottom or fit a copper manifold - I do have some spare piping laying about! Thanks all for the replies.

Reckon it was defo the flexible hose riding up into the grain bed before so I was missing out on some of the grains. If you stir it up and batch sparge, it removes that problem from the equation.