Efficiency.

[mark_68]

G'day,what's the normal efficiency expected when doing a partial mash using a pot as mash tun and sparging through a sieve?I have managed %39.2 on my first attempt and %52.6 for a second attempt,using around 4 litres of 80 degrees water for the sparge.The jovial monk here in adelaide says that i should get %70 using this method,is this about right?I lost 3 degrees during the mash which started at 68 degrees,could this be the cause of my poor efficiency?

[Aussie Claret]

Mark,
There could be a couple of reasons for poor extraction efficiency: -
1. What was your liquor to grain ratio? A common ratio is around 2.5 / 1 (2.5 litres of water for every Kg of grain).
2. Do you mash out? Add some of the sparge water (at above 90c) after you complete your mashing, which will raise the mash temperature to above 70c. This has a two fold effect, it will de-activate the enzymes and will aid flushing of the sugars from the grain. You need to stir and allow to sit for a few minutes (10 mins)
3. Your sparging technique. I would after your mash remove all of the wort that you can then add your sparge water to the panwith grain, stir for a few minutes to help dissolve and remove as much of the remaining sugars then leave for 10 minutes before straining.

As an example lets say you use 1kg of grain, you need 2.5 litres of water to mash, (1 litre will be aborbed by the grain), add approx 0.5 - 1 litre at mash out which should give you 2 - 2.5 litres of first runnings, then sparge with the balance of the sparge water (approx 2litres) to give you another 2litres of 2nd runnings, totalling 4-4.5 litres pre-boil. Checking this SG will determine the amount of sugar removed and will give you your extraction efficiency.

If you have poor efficiency I'd say that it's because you either are not removing sufficient sugar from the grain (sparging) or that you haven't allowed sufficient time (or optimum conditions) during the mash for starch conversion. Mash at 65-67c for one hour.

One last thought what grains were you using? As you need grains that have diastatic enzymes to allow for conversion of starch to sugar. Some speciality grains do not have any or have insufficient to allow complete conversion, in this case you need to add some grains that can aid this conversion (such as galaxy or other base malts).

Cheers
AC

[mark_68]

Thanks for the reply AC,i will use the info next time and see if it makes any difference.I initially used 6 litres of strike water at 76 degrees for 2.4 kilos of grain,which was made up of 2.15 kilos of pilsener malt and 250 gms of crystal malt.It took quite a while to stir the grain in with the water so i lost around 16 degrees during this time,after which i added 1.5 litres of boiling water to bring the temp. back to 68 degrees.The first time i attempted a partial i used a cheap meat thermo. which when checked read 90 degrees in boiling water,so i ditched the thing and bought a 30 cm long glass spirit thermo. which does read 100 degrees in boiling water,so i assume it is accurate.I guess my mash would have been fairly thin against the ratio you gave me so could this have caused the problem?Is there an easier and much faster way of mixing the water with the grains as i lose a fair bit of heat doing this using an uninsulated pot?I will eventually buy a decent esky and convert it with manifold,but for now i have to make do.

[chris.]

IMO I'm not quite sure if a thin mash would soley contribute to a low efficiency. I've done upto 5-6L per kg (no sparge) without too much trouble. My efficiency did drop about 10% to around 60-65% from not sparging though. Are you batch sparging mark?

[Aussie Claret]

Mark as a suggestion, to prevent heat loss, heat the water to about 74c before adding the grains, then slowly add the grain around the edge of you pot then stir the grains in making sure that there are no lumps and that all the grain is wet. Then put in the oven at 65c, if you can control your oven to that temperature that is.

By putting the pot in a warm oven will reduce your chances of dropping too far; obviously you don't want the oven hotter than 70c though as your mash will increase in temp and you wouldn't want to go above 70c in the mash.

AC

[SpillsMostOfIt]

Even if the oven is set to (say) 50degC, you'd get less heat loss than your ambient of (say) 20degC.

[mark_68]

My sparge method is pretty crude as i just ladle the grains into a sieve and then sparge with water at 80 degrees.This was the method i got from Jovial monks forum here in adelaide,he gets 70-75% using this idea.My pot goes into a cardboard box which is lined with polystyrene and a thick quilt,it fits nice and snug in there.I'm thinking that the esky idea is the way to go as i will be able to sparge properly rather than just quickly running hot water through a sieve and avoid possible HSA.Thanks for the replies guys, i will take any ideas on board.

[Trough Lolly]

G'day,what's the normal efficiency expected when doing a partial mash using a pot as mash tun and sparging through a sieve?I have managed %39.2 on my first attempt and %52.6 for a second attempt,using around 4 litres of 80 degrees water for the sparge.The jovial monk here in adelaide says that i should get %70 using this method,is this about right?I lost 3 degrees during the mash which started at 68 degrees,could this be the cause of my poor efficiency?
...
I initially used 6 litres of strike water at 76 degrees for 2.4 kilos of grain,which was made up of 2.15 kilos of pilsener malt and 250 gms of crystal malt.

Like JM, I used to get 70-75% efficiency without any difficulty when ladelling grains from the stockpot into a colander and sparging...From what you've written it seems to me that you haven't sparged enough! You used 2.4kg of grains and that would have soaked up roughly 1.5L of the original 6L of strike water. Then you would have drained out around 4.5 litres of the original mash liquor and sparged with the 4 litres of sparge water giving you around 8.5 litres of sweet wort from the 2.4kg of grains... 8.5 litres of wort from 2.4kg of grains is a pretty poor return. 5kg of grains will easily make 21L of wort. I think you should sparge with at least the same volume again (6L) giving you around 10.5L of wort from the 2.4kg of grains.
It's often the case that new grain brewers either forget or overlook the fact that the grains soak up a substantial quantity (around 57%) of the mash water and you need to factor that in when you try to calculate your pre-boil volume...If you don't have promash or any equivalent brewing software, a rough rule of thumb is to allow for each kilo of grains to soak up 500ml of mash water.
Your mash temps were fine - 68C down to 65C over the mash is well and truly in the "zone".
Other things to consider are the crush of the grains and how well the grains were doughed-in at the start. Sometimes these little details all add up to less than desired efficiency. Another sure sign that you didn't fully convert the available starches in the mash will be starch haze in the fermented beer. Many brewers swear by a 90 min mash, stirring every 15 mins and watching the mashtemp like a hawk.

Cheers,
TL

[SpillsMostOfIt]

I'm one of these brewers Trough Lolly speaks of.

90 minute mash. Stir lots. Keep temperature where I want it (I've been doing a sort of escalator mash in my last few brews - easy with immersion elements and BIAB). I don't watch like a hawk though - I tried it but have trouble keeping my balance on the perch. I either got nearly 85% efficiency last time around or I botched a reading somewhere.

I would expect my efficiency to improve over time as experience grows. You do have to tend to it though - if you don't have some sort of compulsive obsessive disorder, you're behind the 8-ball from the beginning.

[BierMeister]

I am also a 90 minute waiter, but I don't calculate my efficiency as the beer turns out right every time it doesn't bother me if I get 80 or 90% efficiency. I was told by Tom at Jovial Monks that my first all grain was around 85% efficiency and I figured if that was the way I do it every time then I will get the same results (and I have). I find really making an effort to add the grain slowly whilst stirring it in gets it doughed in nicely and add the grain with a 5C addition to the desired temp doies the trick. Having the right grain crush is important too, but if your HBS is crushing it then its probably O.K. I have been stiring it every 15 or so, but in future will stir every half and hour and see how it goes. Stiring keeps the temp regular and spots cold spots from forming. 60 minutes is probably all you need, but I don't check for starch etc.. so I know that by 90 min it's done. This also gives my sparge water time to heat up and me to have lunch so no real time wasted.

Edit: What I meant to say is that with more experience you will pick up things and know when its right. Keep pluging on.

[SpillsMostOfIt]

... but I don't calculate my efficiency as the beer turns out right every time it doesn't bother me if I get 80 or 90% efficiency.

I agree. I reckon you get the mechanical process right and then just do it. I'm still working on that part of mine, so while I am changing things, I measure (occasionally, if I remember).

[OldBugman]

but if your efficiency is all over the shop it'll change your IBU calcs.

I finally found 15% missing efficiency in my last brew but thankfully it only dropped it from 42IBU to 37IBU so she'll be right.

But a different hop schedule with target IBU may have been a drastic difference.

[SpillsMostOfIt]

but if your efficiency is all over the shop it'll change your IBU calcs.

I finally found 15% missing efficiency in my last brew but thankfully it only dropped it from 42IBU to 37IBU so she'll be right.

But a different hop schedule with target IBU may have been a drastic difference.

I hear you. One of my main thrusts at the moment is to achieve consistency of my process so I can spend time on the other bits. I figure that if lots of the stuff that can be mechanical become so, this sort of stuff becomes like walking...

[mark_68]

Next thing on the list is a much bigger pot i think, i need extra boil volume to make things more comfortable.These things are hard to find in adelaide though,so it might take some ringing around.

[drsmurto]

Next thing on the list is a much bigger pot i think, i need extra boil volume to make things more comfortable.These things are hard to find in adelaide though,so it might take some ringing around.

Mercato - Lower NE road in Campbelltown, think they go above 100L in capacity and are very good value. I am looking to get a 50L pot from them asap for my crack at BIAB before heading into AG.

[mark_68]

Thanks mate,i will give them a burl and see what they have for a reasonable price.The best i could find was a 15 litre pot in myers,i want 30 litres at least.