What's your MASH conversion effeciency

[Gnomebrewer]

Pick one. Mash, Lauter or BH. I'm just LMAO wondering how people are calculating these values. I'm obviously using a whole different set of equations

This thread's about mash efficiency. Lauter and BH efficiency have nothing to do with it. My post #26 details how I do my calculations - if I just want an estimate of the efficiency I use my quick method, if I want a more accurate measurement I work out based on ppg for each grain type. Most others seem to be using software. If you don't agree with my equations, let me know.

IME brewers who are getting unrealistically high BH efficiency are putting in more grain than they should be. Eg, I've brewed with a mate who always bragged about 90% BH efficiency, but was dumping about 10% trub (which, of course, would mean that the rest of his process was 100% efficient). It turned out he was rounding down measurements of grain (eg. 732g measured would be recorded as 700g). It's an easy way to boost efficiency! However, achieving MASH efficiency in the 90's isn't too hard if you can crush fine. It's processes downstream of that (especially the lauter) that are harder to do at high efficiency.

 

[SoCal-Doug]

Dont be offended. I didn't have any single post in mind when I questioned anything

Now that you point out your post though... Wow, your 100% mash efficiency is pretty awesome. I think I saw someone else mention 107% though. I'm slackin' in the efficiency department I 'spose. I think i'll sell all my stuff and go pick up a turkey fryer and a Wilshire bag

 

[Gnomebrewer]

Now that you point out your post though... Wow, your 100% mash efficiency is pretty awesome.

You must have read someone else's post. I've never had 100% mash efficiency. I achieve 95% quite easily with a 0.025" crush (actually a bit over), stir several times, and a decent rest at 160. Sometimes it's up to 96 or 97%, but I've NEVER got 100%, even leaving it for an extra hour.

 

[SoCal-Doug]

I was pretty sure you said #27. Guess I read it wrong. I stand corrected with and will correct my statement to: Wow! 95% to 97% mash efficiency is pretty awesome. And is whoever's 100% and whoever's 107%

And I'm still intrigued by whatever math and methods were used to derive those numbers. LOL

 

[Gnomebrewer]

And I'm still intrigued by whatever math and methods were used to derive those numbers. LOL

If your BH efficiency is in the high 80s, your mash efficiency is probably over 95%. Do you measure mash efficiency?

 

[balrog]

...I'm still intrigued by whatever math and methods were used to derive those numbers.

For better or worse, right or wrong, I use the following from http://braukaiser.com/wiki/index.php/Understanding_Efficiency#Conversion_efficiency
I find it a fun number to have, but I do not alter my brew day based on its measurement, yet. When I am finished and sample the FV and measure OG prior to yeast pitch, I may need to dilute with water if I am way off but if low then it's just low.

Latest batch's example was
#grist #qts strike L/Kg ratio MaxEff PreBoil R% MashEff
9.5 30 6.59 10.83 10.7 98.4

Braukaiser:
An approximation of the conversion efficiency, which is most accurate when the conversion is close to 100%, is the ratio between the expected FW extract and the actual FW extract:

where
· CE : conversion efficiency, is the efficiency of the starch conversion in the mash in %
· FWmax is the expected first wort extract that was calculated using the above formula (in Plato, Brix or %)
· FWmeasured is the actual first wort extract that was measured (in Plato, Brix or %)

Peter Hopcroft pointed out that the accurate formula for the conversion efficiency is

The extract content in Plato (close enough to Brix and extract % for these cases) can be estimated form specific gravity with this formula:
Plato = (sg - 1.000) * 1000 / 4

The first wort extract can also be calculated from the mash thickness, which removes the actual grain weight and water volume from the equation:

· R is the water to grain ratio in l/kg. If the mash thickness is known in qt/lb, multiply by 2.09 to convert to l/kg

 

[schematix]

Public Service Announcement: You cannot get >100% conversion efficiency. 100% is the best you can do. No extra credit i'm afraid. You can however get more than you expected, but that doesn't mean you did better than 100%.

Kai's formulas are the foundation of determining mash conversion efficiency. Every grist is different. Even the same grist from different lots is different. Note that each ingredient has its own e_grain and you need to calculate the weighted average of it for your entire grist in order to get a good approximation of your '100%' number.

Kai's formulas are also much easier to deal with when you brew using the Plato scale. The plato scale is the %w/w of sugar in the solution. So a 10 plato beer is 10% sugar by weight (i.e. 1lb of sugar dissolved into a total mass of 10lbs, or 1lb of sugar and 9lbs of water). If you look closely at kai's FW_max formula you'll see they are essentially calculating the mass of sugar you get into your mass of mash water.

 

[balrog]

Public Service Announcement: You cannot get >100% conversion efficiency. 100% is the best you can do.

Agreed. Fully. And without specifics about the grains used, one can never be completely accurate either, not knowing what potential sugar there is.

When used as a measure of the process (in my case) going from buying double crush grist from supplier to using Corona mill, it is just useful data.

 

[Blackdirt_cowboy]

I think when software says you are over 100% mash efficiency, it’s because there’s a difference in the actual amount of starch in the grain versus what the program assumes is in the grain. That, or your scale is off, and you’re mashing more grain than what you think. I’ve had brewers friend tell me I reached 102% mash efficiency before. I know that’s not possible and have attributed to one of the two factors I just mentioned. Of course, there’s always the possibility that the programmed equations are not correct.

I’ve calculated my efficiencies by hand as well, and have always come within a percent or two of what brewers friend tells me. These conversations about efficiency are very difficult to have, as there’s no standard nomenclature. For example: mash efficiency/conversion efficiency; preboil efficiency/lauter efficiency. I have no doubt near 100% MASH efficiency is possible. I have my doubts when homebrewers talk about 85% plus BREWHOUSE efficiency. That’s getting into the territory of the commercial brewers, and I just don’t think our homebrew equipment is capable of that.

 

[Gnomebrewer]

I have my doubts when homebrewers talk about 85% plus BREWHOUSE efficiency. That’s getting into the territory of the commercial brewers, and I just don’t think our homebrew equipment is capable of that.

85%+ is achievable at HB scale, especially with single vessel BIAB (with a fly sparge or dunk sparge in a separate pot + squeeze the bag) and if all trub is dumped into the fermenter (actually I'd believe BIAB efficiency approaching 95% using these methods). Commercial brewers have to pump out from under their mash and don't/can't squeeze the grain and also whirlpool after the boil and leave behind the hot break/trub. Most commercials I'd expect to run in the low to mid 90's, so I'd think 3 vessel HERMS/RIMS mimicking them could realistically run to mid to high 80's. My current RIMS is about 82% BH efficiency, and I leave behind a lot of break material (a big hit to efficiency).

 

[Gnomebrewer]

I use brewer's friend for the calculation.

I can't find a conversion calculator on Brewer's friend. Could you link the one you use?

 

[balrog]

Re BFriend calc, I think all they have is brewhouse and preboil if that's the vols/SG you use, but that makes it after mash/lauter, which is your point I think?

 

[Gnomebrewer]

Re BFriend calc, I think all they have is brewhouse and preboil if that's the vols/SG you use, but that makes it after mash/lauter, which is your point I think?

Yep. In fact, I can't find a mash CONVERSION calculator anywhere - they all want pre-boil gravity and volume, which then includes the efficiency of the lauter/sparge. I'm playing around with Beersmith at the moment (no calculator in it, but it does give measured mash efficiency in the session data....using BS3). There was an earlier comment that it calculates mash efficiency from brewhouse efficiency - this seems to be what it does for the mash efficiency estimate (which makes sense), but it seems to calculate 'Measured Mash Efficiency' independently. After a very quick look, it seems to give percentages a few points higher than what I get from my formula. It may be doing the calculation correctly by converting to mass, calculating percentage sugar by mass (plato) then converting back to SG (as described by Braukaiser). Maybe that gives a few points different to my method, which would explain why I can never get to 100%! It's also worth noting that Kai (Braukaiser) suggests that if mash conversion efficiency is under 90% there is a problem (i.e. 90% is easily achievable).

 

[Gnomebrewer]

I've found a mash conversion calculator on Braukaiser's website. It's an excel spreadsheet
http://braukaiser.com/documents/efficiency_calculator.xls
Plugging in a few basic recipes, it seems that this spreadsheet calculates a couple of point lower than my method, and BS3 a couple of points higher. So, if I've calculated 95% efficiency, BS3 says it's 97 to 98%, Braukaiser says about 93%. I trust Braukaiser's calculators so will now use it instead of my calculation (although mine seems quite reasonable).

 

[balrog]

I just plugged the Kai formulas into Excel and register lbs grain in a cell, qts water, and Refractometer measurement right after mash. Since I BIAB no sparge that's all I need

EG YoopersOatSt#110 10.0lbs, 28qts, R% 12.0, BKaiMashEff=99.1%

 

[Gnomebrewer]

Out of interest, would you mind listing each grain and weight so that I can see what BS3 gives as the mash efficiency?

 

[Gnomebrewer]

Well, after playing around a bit more with mash efficiency in BS3, I've realised that it's a piece of crap for calculations. For some reason it uses measured post-mash gravity and measured pre-boil volume to calculate mash efficiency! So, it's actually calculating some bastardised mix of mash conversion and mash lauter/sparge efficiency that is irrelevent (unless you input your pre-boil gravity in to the post mash gravity field, even though there is a separate place for pre-boil gravity). It was only by random chance when using it earlier that it came close to my calculations! In short, BS3 doesn't calculate conversion efficiency (I'm happy to be corrected if that's incorrect).

 

[Gnomebrewer]

Awesome - for the batch I'm about to brew, my calculation came in the same as Braukaisers.
9.26lbs of Joe White ale malt (1.037, 4% moisture)
0.88lbs of Simpsons Medium Crystal (1.032, 5% moisture)
3.8gallons of mash water = 4.62gallons for the mash (using BS3)

100% efficiency = (9.26x37 + 0.88x32) / 4.62 = 80 points (1.080)
I'll be aiming for somewhere around 1.076 or higher at the end of my mash (before sparging).

 

[wilserbrewer]

Is 107% mash efficiency 7% free beer?
Lol

 

[303Dan]

85%+ is achievable at HB scale, especially with single vessel BIAB (with a fly sparge or dunk sparge in a separate pot + squeeze the bag) and if all trub is dumped into the fermenter (actually I'd believe BIAB efficiency approaching 95% using these methods). Commercial brewers have to pump out from under their mash and don't/can't squeeze the grain and also whirlpool after the boil and leave behind the hot break/trub. Most commercials I'd expect to run in the low to mid 90's, so I'd think 3 vessel HERMS/RIMS mimicking them could realistically run to mid to high 80's. My current RIMS is about 82% BH efficiency, and I leave behind a lot of break material (a big hit to efficiency).

Agreed. I regularly get 82-85% brewhouse efficiency on my 3 vessel eHERMS system and I'm not really striving for high efficiency. I do 60 minute mashes, have a pretty conservative gap set on my mill, and don't stir at all in those 60 minutes.

 

[balrog]

Out of interest, would you mind listing each grain and weight so that I can see what BS3 gives as the mash efficiency?

Bairds Maris Otter - 2.5-3.5L 6.00 pound
Briess Oat Flakes - 2.5L 1 pound
Briess Victory Malt - 28L 12 ounce
Thomas Fawcett Pale Chocolate Malt - 180L 12 ounce
Briess Flaked Barley - 1.4L 8 ounce
Briess Light Roasted Barley - 300L 8 ounce
Warminster Dark Crystal Malt - 65-90L 8 ounce

 

[SoCal-Doug]

For the sake of simplicity, let's take a single malt recipe. 9 pounds of Maris Otter mashed in 6 gallons of water. At the end of the mash time, you take a SG reading before adding water, sparging, or removing grain and draining. This is pure mash efficiency, or "how well did you convert the starches to sugars compared to what the maltster says you should under optimum conditions"

Maris Otter has a "potential" of 38 (1.038sg) per pound per gallon, as determined by their lab tests. This is what the grain is capable of giving you.
With 6 gallons of water, the mash potential becomes 47.5 (1.0475sg) (grainweight X grainpotential / gallons or 9 X 38 / 6)
The end of mash gravity you tested shows 1.040
Divide the tested gravity by the potential mash gravity and the result is 84.2% mash efficiency (40 / 47.5)

The next efficiency rating is lauter efficiency. This says "how well did you rinse the grain and get those sugars out of the grain". Some people call this "preboil efficiency". For our example, let's sparge (or just add if you are not sparging) 1.5 gallons of water to come to a preboil level of 7.5 gallons.

The preboil potential becomes 38 (1.038sg). Same equation with a new volume of water grainweight X grainpotential / gallons. or 9 X 38 / 7.5
You get to your preboil volume of 7.5 gallons, give it a stir, and measure the SG. It shows 1.031.
Your lauter efficiency is 81.6% (31/38)

For multiple grain recipes, simply sum the volume potentials of each grain, then apply the division accordingly to the totals

Brewhouse is basically the above AND how close did you hit your postboil volume versus OG. If you overboil, you can simply add RO or distilled water to bring it back up to your final volume and pretend your BH efficiency was good. If you underboil, you can either (1) recalculate it based on the actual postboil volume (cheating) or (2) drop your BH efficiency. Your choice. I'll skip those calculations for now.

Now let's look at some thoughts...

* If you do a very long mash with no lid, you will lose a little water through evaporation. To calculate mash efficiency correctly, you must know (or at least estimate) how much water you lost and use that volume for the calculation. Otherwise your efficiency value is whacked.

* You can not use the mash volume after you remove the grain for mash efficiency calculations (without knowing absorption volume, which varies by grain weight in a draining situation). Mash efficiency liquor volume include the volume absorbed. Test the SG before removing the grain at the end of the mash cycle.

* If you do not sparge (simply lift the bag out and drain), the efficiency MUST drop compared to an identical recipe that is sparged, because some of the sugars WILL be left in the grain within the absorbed volume, and not rinsed into the boil volume. Period, end of story.

* Larger batches (say 20 gallon versus 5 gallon) will have a slightly lower efficiency. This is why a maltsters "yield" is based on commercial quantities and home brewers can many times beat their yield values by a couple percent. We brew much smaller quantities than they do.

* If you get over 100% efficiency, either (1) the maltster screwed up his testing or labeling or (2) you goofed or (3) you are using some new age math that greatly differs from the above. Or possibly comparing your results to the maltsters "yield" rather than potential, which in many cases could be over 100%.

* In a fairly high-tech 3 vessel system, full time recirculation, stirring the mash every 20 to 30 minutes, long sparges, extremely accurate volume measurements, corrected for temp and shrinkage, and over 20+ years of brewing and engineering, I can achieve 86% to 90% mash and lauter depending on the recipe. I have seen 92 but its very rare. When someone says they can consistently hit mid and high 90's in a BIAB or igloo cooler setup with or without a sparge, i'm sorry, I have to question it.

* BS does calculate mash/conversion efficiency fairly accurately. If they somewhere calculate lauter efficiency, I cant find it. Their BH efficiency never follows or agrees with simple math for me.

* Without accurate volume measurements, all bets are off. There is no need to calculate any efficiency. Guessing does a brewer no good.

* Don't be offended. As i've said before, i've seen kitchen stove extract brewers take best of show in competitions. ALL methods can brew excellent beer and there is nothing wrong with any method you use. Just brew and enjoy with whatever you have!

 

[Gnomebrewer]

With 6 gallons of water, the mash potential becomes 47.5 (1.0475sg) (grainweight X grainpotential / gallons or 9 X 38 / 6)
The end of mash gravity you tested shows 1.040
Divide the tested gravity by the potential mash gravity and the result is 84.2% mash efficiency (40 / 47.5)

Not quite. You must consider the entire mash volume, not just the strike water volume. Using https://www.rackers.org/calcs.shtml the mash volume is 6.9 gallons. So mash potential is
9 x 38 / 6.9 = 49.6 (1.0496). But your initial calculation was off (9 x 38 / 6 = 57, not 47.5). If you are typically getting around 85% efficiency using strike water volume in your calculation, your actual conversion efficiency, using full mash volume in the calculation, will be around 95% to 100%.

The next efficiency rating is lauter efficiency. This says "how well did you rinse the grain and get those sugars out of the grain". Some people call this "preboil efficiency". For our example, let's sparge (or just add if you are not sparging) 1.5 gallons of water to come to a preboil level of 7.5 gallons.

The preboil potential becomes 38 (1.038sg). Same equation with a new volume of water grainweight X grainpotential / gallons. or 9 X 38 / 7.5
You get to your preboil volume of 7.5 gallons, give it a stir, and measure the SG. It shows 1.031.
Your lauter efficiency is 81.6% (31/38)

Yes, you'll need to add more than 1.5 gallons though. Again, math is not quite right though
9 x 38 / 7.5 = 45.6. The method is sound though.

* If you do a very long mash with no lid, you will lose a little water through evaporation. To calculate mash efficiency correctly, you must know (or at least estimate) how much water you lost and use that volume for the calculation. Otherwise your efficiency value is whacked.

Good point. Even with a lid, some steam would leave every time you remove the lid. I wonder if this is a source of some of the >100% efficiencies

* BS does calculate mash/conversion efficiency fairly accurately. If they somewhere calculate lauter efficiency, I cant find it. Their BH efficiency never follows or agrees with simple math for me.

BS3 doesn't calculate mash/conversion efficiency (I don't know about BS2). It uses post-mash gravity and pre-boil volume to calculate, which is not correct. If you put your Pre-boil gravity in to the post-mash gravity field, you'll get lauter efficiency. I'm assuming it's an error with BS3, maybe BS2 was better.

* Without accurate volume measurements, all bets are off. There is no need to calculate any efficiency. Guessing does a brewer no good.
!

Absolutely!

 

[Gnomebrewer]

Bairds Maris Otter - 2.5-3.5L 6.00 pound
Briess Oat Flakes - 2.5L 1 pound
Briess Victory Malt - 28L 12 ounce
Thomas Fawcett Pale Chocolate Malt - 180L 12 ounce
Briess Flaked Barley - 1.4L 8 ounce
Briess Light Roasted Barley - 300L 8 ounce
Warminster Dark Crystal Malt - 65-90L 8 ounce

Thanks and sorry to waste your time, but I realised BS3 is faulty anyway, so can't try it out.

 

[balrog]

@SoCal-Doug , thanks. Interesting read and I've no doubt I'm calculating things about which I've limited understanding.

What really matters to me is knowing what will likely happen. I'm much more interested in having the OG come out, in the fermenter, with the volume I plan. If it's off 10 points, I'm going to adjust things next time but I'm finding (wheat being the main culprit) recipes that I make repeatedly require certain overall brew house efficiency targets. I cannot say all my recipes will be 76% or whatnot. But I'm only really aiming at repeatability frankly. The rest of these numbers are just dataphile candy to me.

 

[RM-MN]

@SoCal-Doug , thanks. Interesting read and I've no doubt I'm calculating things about which I've limited understanding.

What really matters to me is knowing what will likely happen. I'm much more interested in having the OG come out, in the fermenter, with the volume I plan. If it's off 10 points, I'm going to adjust things next time but I'm finding (wheat being the main culprit) recipes that I make repeatedly require certain overall brew house efficiency targets. I cannot say all my recipes will be 76% or whatnot. But I'm only really aiming at repeatability frankly. The rest of these numbers are just dataphile candy to me.

Wheat and rye are always a problem with efficiency because the kernels are smaller and harder so unless the mill is adjusted tighter they do not get well crushed. If you own the mill you can adjust that for doing wheat or rye beers. Otherwise you accept the grains as they are milled and plan for lower efficiency for which you offset by adding more grains.

 

[Gnomebrewer]

Wheat and rye are always a problem with efficiency because the kernels are smaller and harder so unless the mill is adjusted tighter they do not get well crushed.

A corona mill is really good for this.

 

[schematix]

Clocked in another 100% (actually better) mash efficiency today, even with a nearly stuck sparge. Malt spec sheets said i should get better than 13.7 Plato, and i got 14.0 Plato.

 

[GoeHaarden]

Clocked in another 100% (actually better) mash efficiency today, even with a nearly stuck sparge. Malt spec sheets said i should get better than 13.7 Plato, and i got 14.0 Plato.

 

[pretzelb]

Not quite. You must consider the entire mash volume, not just the strike water volume. Using https://www.rackers.org/calcs.shtml the mash volume is 6.9 gallons. So mash potential is
9 x 38 / 6.9 = 49.6 (1.0496). But your initial calculation was off (9 x 38 / 6 = 57, not 47.5). If you are typically getting around 85% efficiency using strike water volume in your calculation, your actual conversion efficiency, using full mash volume in the calculation, will be around 95% to 100%.


Yes, you'll need to add more than 1.5 gallons though. Again, math is not quite right though
9 x 38 / 7.5 = 45.6. The method is sound though.


Good point. Even with a lid, some steam would leave every time you remove the lid. I wonder if this is a source of some of the >100% efficiencies


BS3 doesn't calculate mash/conversion efficiency (I don't know about BS2). It uses post-mash gravity and pre-boil volume to calculate, which is not correct. If you put your Pre-boil gravity in to the post-mash gravity field, you'll get lauter efficiency. I'm assuming it's an error with BS3, maybe BS2 was better.


Absolutely!

Why are you saying in this example that the mash volume is 6.9 with only 6 gallons of water? Are you saying that 6.9 gallons of water should have been used or that when adding 6 gallons of water the actual number to use in the formula is 6.9?

 

[Gnomebrewer]

Why are you saying in this example that the mash volume is 6.9 with only 6 gallons of water? Are you saying that 6.9 gallons of water should have been used or that when adding 6 gallons of water the actual number to use in the formula is 6.9?

The total mash volume is 6.9 gallons. That's strike water (6 gallons) + grain. According to the calculator here
https://www.rackers.org/calcs.shtml
grain adds 0.08 gallons/pound to mash volume.

Edit: the mash volume should have been 6.7 gallons, not 6.9 (my mistake trying to use stupid imperial measurements!).

 

[schematix]

View attachment 596294

I know you're just messing with me, but i'll throw some numbers out as an example for anyone trying to follow the madness. This is from my own recipe spreadsheet. It's designed to make it easy to hit target volumes at a target strength.

1. The recipe

30lbs of grain at a weighted average of 78.03% extractable sugars (as determined by a malt spec sheet) into 17 3/4 gal of water in theory yields a wort of 13.67 %w/w (Plato) first wort. I do no sparge so this wort is further strengthened by boiling from 14.4 G to 13.6 G, giving me an estimated post-boil wort gravity of 14.47 Plato. In reality my mash gravity was just a touch over the expected value at n=1 by about 0.1 P.

2. The result. Post boil wort was 14.7P. So i was high by about 0.2P, or about 1 SG point. Well within the margin of measurement error of grain/water/instruments.

100% conversion is achievable for anyone who wants it.

 

[GoeHaarden]

I know you're just messing with me...100% conversion is achievable for anyone who wants it.

Lol. I was just messing with you. I'm beginning my quest for the mythical creature of 100% mash conversion. Trying out BIAB instead of multi-vessel so we'll see how it goes. I think the mindset that homebrewers can't achieve such numbers is quite naive.

On a serious note...I'm just here admiring your clear-a$$ sample you posted!!

 

[Gnomebrewer]

@schematix I'm not sure where you're getting 13.67p from. Grain mass is 13.608Kg. Weighted extract percentage is 78.03%, giving 10.62Kg of extractable sugar.
17.75 gallons of strike water is 67.19 Litres. at 152F has a mass of about 65.856Kg. Total mass of the mash is 13.608 + 65.856 = 79.464Kg. w/w sugar = 10.62 / 79.464 x 100 = 13.36%. If the water was measured cooler (i.e. density closer to 1Kg/Liter), the mas would be even greater thus w/w slightly lower still. Am I missing something? (I normally use volume and SG units, so could be wrong with this).

Edit: If we assume your 67.19 litres of water had a mass of 67.19Kg, your 100% efficiency would yield a wort of 13.1P, meaning you achieved about 105% efficiency. This suggests either a better than expected yield of grain or measurement error.

 

[schematix]

@schematix I'm not sure where you're getting 13.67p from. Grain mass is 13.608Kg. Weighted extract percentage is 78.03%, giving 10.62Kg of extractable sugar.
17.75 gallons of strike water is 67.19 Litres. at 152F has a mass of about 65.856Kg. Total mass of the mash is 13.608 + 65.856 = 79.464Kg. w/w sugar = 10.62 / 79.464 x 100 = 13.36%. If the water was measured cooler (i.e. density closer to 1Kg/Liter), the mas would be even greater thus w/w slightly lower still. Am I missing something? (I normally use volume and SG units, so could be wrong with this).

Yah...

We take the density measurements at room temp (usually 60F or 68F). 100lbs of water at room temp is 100lbs at boil. I'm basing my strike water mass on room temp mass. Sugar still weighs the same at room temp as at boil. Densities of both do change at different temperatures but we're only concerned with the ones taken at room temp.

When you add the sugar to your water the denominator becomes the mass of water plus mass of dissolved sugar. So plato = sugar / (water + sugar).


I'm doing to do this in english units even though they make no sense.

17.75 G * 8.33 lb/gal (density at room temp) = 147.9 lb

Extract sugar = 78.03% of 30lb = 23.4 lb

Plato (%w/w) = 23.4 / (147.9 + 23.4) = 13.66%

 

[Gnomebrewer]

Yah...
We take the density measurements at room temp (usually 60F or 68F). 100lbs of water at room temp is 100lbs at boil. I'm basing my strike water mass on room temp mass. Sugar still weighs the same at room temp as at boil. Densities of both do change at different temperatures but we're only concerned with the ones taken at room temp.

Yes, 100lbs of water at room temp is 100lbs at boil, but 17.75 gallons at room temp doesn't have the same mass as 17.75 gallons at boil. Presumably you directly measure the volume of water, not mass, so the temperature the water is measured at is important.

When you add the sugar to your water the denominator becomes the mass of water plus mass of dissolved sugar. So plato = sugar / (water + sugar).

Yes, and I realised my mistake was using water+grain for the denominator, not water+sugar

I'm doing to do this in english units even though they make no sense.

17.75 G * 8.33 lb/gal (density at room temp) = 147.9 lb

Extract sugar = 78.03% of 30lb = 23.4 lb

Plato (%w/w) = 23.4 / (147.9 + 23.4) = 13.66%

The only thing missing is consideration of the grain moisture. For example, for Briess C20, Extract is 76% on a dry basis, but contains 6% moisture. This 6% must be considered. Canada maltings rye is also given on a dry basis. I'm not sure about Briess 2-row. This seems to be an illogical way for extract % to be given, an as-is basis seems much more useful, but it is what it is. Considering grain moisture, your 100% extract should be about 13P.

 

[schematix]

Yes, 100lbs of water at room temp is 100lbs at boil, but 17.75 gallons at room temp doesn't have the same mass as 17.75 gallons at boil. Presumably you directly measure the volume of water, not mass, so the temperature the water is measured at is important.

You are correct that the density changes, but you aren't thinking about it correctly when it's mass and when it's volume.

My initial strike water measurement is in terms of volume, but its correlated to mass by its density at room temp (8.33lb/gal). If i put in 17.75 * 8.33 = 147.85 lbs of room temp water, i always have 147.85 lbs of water in the system regardless of its temperature. This is a simple conservation of mass scenario. The mass of water doesn't change throughout the mash even though the temperature could be changing.

And again the *measurement* is taken at room temp. Brewers report densities at room temp (if they don't then they are doing it wrong). Sure in the mash or at boil the density is different, but i'm not floating my hydrometer in a boiling cauldron of wort, nor is my refractometer measuring a hot sample once a few drops of liquid come to equilibrium with the devices temperature.

The only thing missing is consideration of the grain moisture. For example, for Briess C20, Extract is 76% on a dry basis, but contains 6% moisture. This 6% must be considered. Canada maltings rye is also given on a dry basis. I'm not sure about Briess 2-row. This seems to be an illogical way for extract % to be given, an as-is basis seems much more useful, but it is what it is. Considering grain moisture, your 100% extract should be about 13P.

e is the extract potential considering moisture content. One such formula i've seen published is e = (DBFG / (1 + MC) - 0.002).

e is not DBCG is not DBFG

13P was not my 100% extract number. It was 13.66 P according to the malt sheets i had. My actual mash gravity at lautering was around 13.7 P (14.0 Brix WRI).

 

[Gnomebrewer]

You are correct that the density changes, but you aren't thinking about it correctly when it's mass and when it's volume.

My initial strike water measurement is in terms of volume, but its correlated to mass by its density at room temp (8.33lb/gal). If i put in 17.75 * 8.33 = 147.85 lbs of room temp water, i always have 147.85 lbs of water in the system regardless of its temperature. This is a simple conservation of mass scenario. The mass of water doesn't change throughout the mash even though the temperature could be changing.

Yes I am thinking about it correctly. As are you (I'm not questioning your calculation of water mass). I was simply putting in two options because I didn't know if you were measuring the volume at room temperature or at mash temperature. Can you see that the temperature at which water volume is measured affects it's mass? At no point have I suggested the mass of the water changes, so I don't see your point in referring to basic laws of physics.

e is the extract potential considering moisture content. One such formula i've seen published is e = (DBFG / (1 + MC) - 0.002).

e is not DBCG is not DBFG

Yes, e should be the potential considering moisture content. It seems highly coincidental that your values match the published data sheets for both grains without consideration of moisture content.

 

[North_of_60]

Wow! I might not be smart enough to make Beer.

 

[schematix]

Yes I am thinking about it correctly. As are you (I'm not questioning your calculation of water mass). I was simply putting in two options because I didn't know if you were measuring the volume at room temperature or at mash temperature. Can you see that the temperature at which water volume is measured affects it's mass? At no point have I suggested the mass of the water changes, so I don't see your point in referring to basic laws of physics.


Yes, e should be the potential considering moisture content. It seems highly coincidental that your values match the published data sheets for both grains without consideration of moisture content.

I’m not sure what your point is here. I’ve stated all along that the density of water depends on temp. But once you use that density to obtain a mass of water, the mass doesn’t change.

I hit my densities and volumes consistently to within fractions of a Plato using this. This isn’t an isolated scenario. I also have good measuring tools and take multiple measurements throughout the process so if you’re going to say I’m calculating all of this wrong and should be getting much less you need to provide a real plausible scenario where I’ve screwed up. I don’t mind being proved wrong, but I don’t think I’m wrong in this case.