Grain Extraction Efficiency
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vlbaby
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Damon,
I find that the efficiency is dependant on so many factors, especially you grain to water ratio, the amount of sparge water you've used, the method of sparging etc etc. You will need to give more info on your setup, and how you have calculated your efficiency.
vlbaby.
I find that the efficiency is dependant on so many factors, especially you grain to water ratio, the amount of sparge water you've used, the method of sparging etc etc. You will need to give more info on your setup, and how you have calculated your efficiency.
vlbaby.
My brewing setup uses 25L food grade plastic pails with heating elements in the bottom. The base diameter is about 32cm and the top diameter is about 36cm. My first mash lauter tun was 2 of these buckets, one inside the other with a heating element in the bottom bucket. This had a dead volume of about 5L which I thought was affecting the efficiency. Then I upgraded my system to a HERMS with the mash lauter tun using a Phils phalse bottom which sits on the bottom of the bucket with a tap directly underneath so no dead space and a pump to move the wort. Unfortunately no improvement in efficiency! I use a Phils sparger for sparging with gravity to feed the hot water. This usually takes about 30-45 minutes for 20L. I always use about 20L of sparge water, ideally to get a start boil volume of around 22L for a final post boil volume of 20L.To crush grain I use a Porkert grain mill and try to have a grist not too fine to avoid sparging problems but all grain is definitely crushed/torn. My last brew used 2.7L/kg of grain with the same efficiency result. I measured the gravity of wort produced at the beginning/middle/end of sparging which gave gravities of 1.077/1.045/1.010 respectively (all were adjusted for temperature). The way efficiency was calculated is by using 1.038 points per pound gallon which I converted to metric and then used on my last 6 brews which all gave around the 55% mark. I have since got Promash and using an efficiency of 55% it seems to give the exact real starting gravity of my wort. What else should I look at?
Damon
Damon
Pat Casey
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Damon,
How many kg of grain, how many litres of wort - including kettle wastage, and at what gravity?
Effeciency as a % is a comparison between what you get and a theoretical maximum obtained for a particular malt in a lab.
Points of gravity per pound per gallon is usd by amateurs in the US, generally anythiing above 30 is pretty good. Remember that it is the 3.79 litre type of gallon they use. Dave Miller is a couple of his books lists the maximums for various fermentables, and from memory I don't think he lists anything as a high as 38 for any grain.
A system I use for both myself and customers is litres including kettle wastage multiplied by points of gravity divided by kgs of grain. Eg 25 litres x 40 points divided by 4 kg = 250, which means that 1 kg of grain will give you 5 litres at a gravity of 50 points. For a mash and sparge you can expect to get a figure of somewhere between 240 and 260. The main purposes of this calculation are to give you a handle on your consistency and to help with recipe formulation.
However the most important thing is what's in the glass rather than any measure of effeciiency.
Pat
How many kg of grain, how many litres of wort - including kettle wastage, and at what gravity?
Effeciency as a % is a comparison between what you get and a theoretical maximum obtained for a particular malt in a lab.
Points of gravity per pound per gallon is usd by amateurs in the US, generally anythiing above 30 is pretty good. Remember that it is the 3.79 litre type of gallon they use. Dave Miller is a couple of his books lists the maximums for various fermentables, and from memory I don't think he lists anything as a high as 38 for any grain.
A system I use for both myself and customers is litres including kettle wastage multiplied by points of gravity divided by kgs of grain. Eg 25 litres x 40 points divided by 4 kg = 250, which means that 1 kg of grain will give you 5 litres at a gravity of 50 points. For a mash and sparge you can expect to get a figure of somewhere between 240 and 260. The main purposes of this calculation are to give you a handle on your consistency and to help with recipe formulation.
However the most important thing is what's in the glass rather than any measure of effeciiency.
Pat
Pat Casey
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Damon
With your figures I get 183. For a conventional mash and sparge you should expect something in the range of 240 - 260.
Have you checked your hydormeter? It could have a crack and liquid has got inside causing it to float lower to give a lower reading.
Pat
With your figures I get 183. For a conventional mash and sparge you should expect something in the range of 240 - 260.
Have you checked your hydormeter? It could have a crack and liquid has got inside causing it to float lower to give a lower reading.
Pat
this sounds like something along what i was getting and discovered i was plugging in the 'wrong' numbers. i was always hitting 55-50% and for the life of me couldn't figoure out what was going on.
jayse, pedro and jasony helped me sort out what i was doing.
for my info check this out
http://www.aussiehomebrewer.com/forum/Prom...ency-t5531.html
basically i was using the wrong number for my batch size.
i brew 12L so i set my batch size to that. however i was telling promash i was getting 12L in the fermenter (including boil off etc) which is kinda back to front. knowing my figures for boil off etc, my batch size should have been set at 17L and my total was around 12L. by doing this i went for 50% to 75% in one easy step.
i hope that helps.
jayse, pedro and jasony helped me sort out what i was doing.
for my info check this out
http://www.aussiehomebrewer.com/forum/Prom...ency-t5531.html
basically i was using the wrong number for my batch size.
i brew 12L so i set my batch size to that. however i was telling promash i was getting 12L in the fermenter (including boil off etc) which is kinda back to front. knowing my figures for boil off etc, my batch size should have been set at 17L and my total was around 12L. by doing this i went for 50% to 75% in one easy step.
i hope that helps.
Sean
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For best accuracy, you should be measuring the volume you get out of the mash tun, into the kettle, and the gravity of that, and using that to do the calculations. What we are determining is mash efficiency, not the efficiency of the whole system.Damon said:
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When taking your sg in the boiler after you have completed runoff, stir the wort really well so that it is uniform, take a sample, crash cool it and then measure the sg.
The calibration of the hydrometer goes way off with changes in temperature, and the recalibration temperature charts are not very accurate.
Crash cool the sample by placing it in a plastic bag and leaving it in an ice slurry mix or in the freezer. Make sure it is at the temperature your hydrometer is accurate at. This will be written somewhere on the scale.
The calibration of the hydrometer goes way off with changes in temperature, and the recalibration temperature charts are not very accurate.
Crash cool the sample by placing it in a plastic bag and leaving it in an ice slurry mix or in the freezer. Make sure it is at the temperature your hydrometer is accurate at. This will be written somewhere on the scale.
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