Do people report mash efficiency or brewhouse efficiency?

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thisoneguy

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Just what the question says... I made my second AG batch this weekend. I got a Barley Crusher and based on many of the posts on here, I expected (perhaps due to a misunderstanding of what people were posting about) to see my brewhouse efficiency hit the 80's.

My mash efficiency was about 82%, but my overall brewhouse efficiency was only 68% (both according to Beersmith). FWIW, this batch was a single infusion, batch sparge.

I know that there are things that I can change to increase my efficiency, but I'm really wondering if there was even a problem? When people are reporting mid- to high-80's for efficiency, should I just assume they're talking about mash efficiency only? Or should I be refining my process to aim for the 80's as my overall brewhouse efficiency?

Thanks! I'm new to brewing in the last 6 months or so, and you guys (and ladies) here on HBT have really helped shorten my learning curve... I feel like I'm on the road from "drinkable" beer to "good" beer - to my taste buds, at least - in a very short time. Cheers!
 

two_hearted

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In my opinion, people get too hung up on efficiency. As long as your in the 60s or 70s your doing just fine. I would shoot more for consistency and just adjust your recipe to your consistent brew house efficiency. If you're getting up in the mid to high 80s you probably need to start worrying about tannin extraction. I'd rather be consistently at 68% and have to buy an extra handful of base malt each time. You're still going to make good beer.
 
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thisoneguy

thisoneguy

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maxam said:
I'd rather be consistently at 68% and have to buy an extra handful of base malt each time. You're still going to make good beer.
This is a good summary of how I feel. I'm not going pro and doing this for money anytime soon, so I'm not going to sweat it if my efficiency isn't super high. I'll just take some more base malt out of the giant 50-lb sack I just bought to make up for it.

This was just the first time I was able to take enough measurements to calculate efficiency, so I was curious what could have caused the discrepancy between what I expected and what I achieved. The more I read, I actually think there isn't any discrepancy... my mash eff was >80 and I think those #'s seem to be the most reported.
 

asterix404

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People report mash efficiency. Brew house efficiency is something I have read about but never really understood. I would agree whole heartedly about consistency. In this scale adding more grain is a perfectly viable option for a very long time. Eventually you will get an adjustable grain mill and start fiddling with it and condition your grain and fiddle some more with it and get into the high 80's or even high 90's.

They also report actual yield which is very different from theoretical yield. That has to do with taking out the parts of the grain which won't convert to anything if I remember from a book I read a long time ago.
 

stux

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People report both.

Unless they say "Into Fermenter" or "Into Boil" or words to that effect you can't really be sure
 

broadbill

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This thread indicates that people are very confused about efficiency.

People report brewhouse efficiency, not mash efficiency (also know as conversion efficiency).

From Kaiser's website:

brewhouse efficiency = conversion efficiency * lauter efficiency

Conversion/Mash efficiency is the how effective you are at converting starches to sugars in the mash step.

Lauter efficiency is the how effective you are at removing/rinsing those sugars from the mash so the end up in your brew-pot.

If you are taking a gravity reading on a sample that has left the mash-tun (i.e. runnings), you are looking at brewhouse efficiency. This is because you can't separate the conversion efficiency from the lauter efficiency; whatever you get for gravity is a product of both of these factors.

Hope this helps...this is required reading if you want to understand this fully:

Troubleshooting Brewhouse Efficiency - German brewing and more
 

broadbill

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People report both.

Unless they say "Into Fermenter" or "Into Boil" or words to that effect you can't really be sure
The only reason those two numbers are different is because the volume has been reduced by a boil step. Efficiency has nothing to do with why these numbers are different. Your efficiency has already been determined by your process upstream of the boil step.
 

matalec1984

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So in essence what you are saying broadbill is that after I finished my sparge and have collected all of my liquid from my tun. If I pull out a sample and take a pre-boil gravity reading of that sample (of course letting it cool down enough to get an accurate hydrometer reading) then I am taking a reading of my brewhouse efficiency?
 

wilserbrewer

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The actual brewhouse efficiency is measured for an entire system. Unlike the dry grain yield or potential measured in a lab, real brewers achieve only a percentage of the ideal number due to real considerations such as efficiency of the mashing process, and losses due to boiling, deadspace or trub. This percentage of the potential, as measured across the whole system into the fermenter, is the brewhouse efficiency.

A related term is mash efficiency. Unlike brewhouse efficiency, mash efficiency measures only the efficiency of the mash and sparging steps. Mash efficiency can be through of as the percent of potential fermentables extracted during the mashing process that actually make it into the boiler.


excerpt from link below

Brewhouse Efficiency for All Grain Beer Brewing | Home Brewing Beer Blog by BeerSmith
 

broadbill

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So in essence what you are saying broadbill is that after I finished my sparge and have collected all of my liquid from my tun. If I pull out a sample and take a pre-boil gravity reading of that sample (of course letting it cool down enough to get an accurate hydrometer reading) then I am taking a reading of my brewhouse efficiency?
yep. Whatever your gravity is at that point (going into the kettle) is a result of the starches you were able to convert to sugars in the mash step (conversion efficiency) and what sugars you were able to rinse away from the grains/mash bed (lauter efficiency).

That number you calculate after mash/sparge is your brewhouse efficiency. As for a guideline, anything between 60-80% is good, and I agree with the others that consistency is the most important.

If you are interested in getting better efficiency, again I recommend that you read Kaiser's link I posted above. I will tell you that based on what I've seen on this forum--if you are batch sparging I would guess your problem is your crush (you aren't crushing fine enough). If you are fly sparging--it could very well be an issue with either crush or fly sparge technique.

Good luck!
 

asterix404

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So I will agree that this is crazy, but I believe that brew house efficiency is what your FG is out of a theoretical maximum possible yield based on a powered crush. So yes, I was wrong. People would typically report the 85% as the total brew house efficiency.

The mash efficiency is calculated much the same way but that one has a different theoretical maximum.
 

matalec1984

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So it seems that we have to competing theories here. Broadbill saying that brewhouse efficiency is measured from the run-off post mash and sparging, while others are saying that that is simply the mash efficiency and the brewhouse efficiency entails the entire process including the boil etc.

To be honest prior to this thread I was under the later impression that the runnings from the mash simply gave you the mash efficiency. I read that beersmith article and that seems to be what they are suggesting as well.

I thought I had it figured out prior to this thread !!!!
 

asterix404

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Oh sorry, I see my post was fairly opaque. The runnings from the mash give you your mash efficiency calculated from a different theoretical base than your brew house efficiency.

Typically people will present the brew house efficiency. The theoretical dry crush yield (essentially powder) is used as this base, meaning 100% efficient. This is measured by the SG once your wort has cooled at the end of the boil before you add yeast. I believe (And I might be mistaken) but this primarily measures efficiency of ferment-ables into your wort. If I am someone please correct me.

The mash efficiency is how well various stuff is extracted from the grain during the mash. There is actually an "original gravity" here too which basically is the SG from cooled wort before a boil. This might be reported but typically you will see this prefaced by the "my OG from the mash before the boil is...". This uses a different theoretical base from the brew house efficiency. I have used the mash efficiency to figure out how much stuff is actually dissolved since the total gravity points in the wort will not change as you boil. This is useful for figuring out if you should add DME and how much. I have done this exactly twice in 5 years, my beer comes out a bit higher or a bit lower than expected, life continues onward.
 

broadbill

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So it seems that we have to competing theories here. Broadbill saying that brewhouse efficiency is measured from the run-off post mash and sparging, while others are saying that that is simply the mash efficiency and the brewhouse efficiency entails the entire process including the boil etc.

To be honest prior to this thread I was under the later impression that the runnings from the mash simply gave you the mash efficiency. I read that beersmith article and that seems to be what they are suggesting as well.

I thought I had it figured out prior to this thread !!!!
It seems that we do have competing theories!

I guess it comes down to if you use Beersmith or not.

I'm under the impression that when you see the term "efficiency", by-and-large it is referring to what BS calls "mash efficency". I think mash efficiency is a poor term as it is frequently mistaken for "conversion efficiency". It should really be called "mash/sparge efficiency" for clarity purposes.

I fall into Kaiser's camp and call my brewhouse efficiency what BS calls mash efficiency. For me an efficiency calculation that takes into account volume losses on my system (trub, deadspace, etc) (i.e. BS's brewhouse efficiency calculation) isn't a particularly useful one for many reasons.
 

mthompson

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I calculate both efficiencies, and see them as this:

Mash efficiency is the percentage of total theoretical sugars possible that I converted and collected during the mash and sparge. Calculated by SG and volume of each running, and a sum of them...total volume collected and SG. This Saturday, my preboil sum was 7.75gal at 1.048 SG and a calculate 80.47% mash efficiency for the grist.

Brewhouse efficiency is the percentage of total theoretical gravity points for a specific volume of wort that you pour into your fermenter. Since I don't lose any of the wort after the mash (i.e. I dump my entire kettle into the fermenter; no spilling, no pump loss, etc.), my brewhouse efficiency is roughly the same as my mash efficiency. This is because the amount of sugars is still the same, just in a concentrated form.

If your process results in a net loss of sugars along the way to the fermenter, then your brewhouse efficiency must be less than your mash efficiency, simply because the amount of sugars you started the boil with are now the new "ceiling" for 100% efficiency during boil and transfer to the fermenter.

By calculating both, and taking readings throughout your process, you can start seeing where you could improve your process. Or, at least figure out where you lost that half-gallon and then figure that into your future batches.

I measure the following:
  • I one-time measured that I lose 0.1 gal from mash deadspace
  • First runnings volume and SG
  • Second runnings volume and SG
  • Third runnings volume and SG
  • Total preboil volume and SG
  • Volume halfway through boil (for boil off percentage, and adjustment if necessary)
  • Total volume and Gravity into fermenter
  • Total volume out of vermenter (if possible, i.e. bottling or secondary. Keg volume is hard to measure.)


Does that make sense?
 

broadbill

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Oh sorry, I see my post was fairly opaque. The runnings from the mash give you your mash efficiency calculated from a different theoretical base than your brew house efficiency.

Typically people will present the brew house efficiency. The theoretical dry crush yield (essentially powder) is used as this base, meaning 100% efficient. This is measured by the SG once your wort has cooled at the end of the boil before you add yeast. I believe (And I might be mistaken) but this primarily measures efficiency of ferment-ables into your wort. If I am someone please correct me.

The mash efficiency is how well various stuff is extracted from the grain during the mash. There is actually an "original gravity" here too which basically is the SG from cooled wort before a boil. This might be reported but typically you will see this prefaced by the "my OG from the mash before the boil is...". This uses a different theoretical base from the brew house efficiency. I have used the mash efficiency to figure out how much stuff is actually dissolved since the total gravity points in the wort will not change as you boil. This is useful for figuring out if you should add DME and how much. I have done this exactly twice in 5 years, my beer comes out a bit higher or a bit lower than expected, life continues onward.
I have only seen the efficiency calculation done on the same theoretical maximum (powder crush) potential of the grains. There is no difference if you are calcuating it pre-boil (coming out of the MT), post-boil, or at pitching. From the standpoint of gravity, the only difference between those three points is volume of wort you have.
 

matalec1984

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I measure the following:
  • I one-time measured that I lose 0.1 gal from mash deadspace
  • First runnings volume and SG
  • Second runnings volume and SG
  • Third runnings volume and SG
  • Total preboil volume and SG
  • Volume halfway through boil (for boil off percentage, and adjustment if necessary)
  • Total volume and Gravity into fermenter
  • Total volume out of vermenter (if possible, i.e. bottling or secondary. Keg volume is hard to measure.)


Does that make sense?[/QUOTE]

Yes it does, so let me expand a little more on my question at the moment.

Yesterday's brew had a preboil gravity of 1.042 and I collected 7 gal for my boil. So based on my understanding of efficiency calculations I took 7 * 42 divided that by my total amount of grain (9.75) and then divided that into 36 for a mash efficiency of 87.7%

During my boil I boiled of approx 1.5 gal and left a little less then .5 gal behind with the trub in order to put 5 12/8 gal into my primary fermenter. Would the amount of boil off and wort left behind decrease my overall brewhouse efficiency based on what your saying.

I know we are splitting hairs and as long as the beer tastes good that really is all that matters, but I find this to be a fairly interesting concept and am trying to iron it all out.
 

Shockerengr

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The only reason those two numbers are different is because the volume has been reduced by a boil step. Efficiency has nothing to do with why these numbers are different. Your efficiency has already been determined by your process upstream of the boil step.
Nope.

There are lots of losses that can occur between the two steps.

Some examples that I deal with (and that drop my brewhouse efficiency)

Hop absorption (an issue with whole hops)
boil kettle deadspace
plumbing losses

All of those result in sugars being left behind.
 

broadbill

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Nope.

There are lots of losses that can occur between the two steps.

Some examples that I deal with (and that drop my brewhouse efficiency)

Hop absorption (an issue with whole hops)
boil kettle deadspace
plumbing losses

All of those result in sugars being left behind.
Well, what I said was:

"For me an efficiency calculation [brewhouse efficiency] that takes into account volume losses on my system (trub, deadspace, etc)..."

I'm well aware that there are more factors than what I listed, I left them out for the sake of brevity. I still don't think it is a very useful calculation, despite my omission.
 

mthompson

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Yesterday's brew had a preboil gravity of 1.042 and I collected 7 gal for my boil. So based on my understanding of efficiency calculations I took 7 * 42 divided that by my total amount of grain (9.75) and then divided that into 36 for a mash efficiency of 87.7%
The actual numbers for the calculation of mash efficiency depends on your grain bill; i.e. 2-row has more potential than roasted barley, thus a higher ppg value. Your formula looks correct though. I like to think in terms of percentages, so I use values and calculations based on the extract potential of the grains.

I typically use Kai's Efficiency Spreadsheet for my calculations and change the extract potential based on the grains I am using (you should be able to get a copy of the malt analysis from the LHBS or an average from the Maltster's website). You can read more about his spreadsheet here: https://www.homebrewtalk.com/f36/efficiency-analysis-spreadsheet-107911/

During my boil I boiled of approx 1.5 gal and left a little less then .5 gal behind with the trub in order to put 5 12/8 gal into my primary fermenter. Would the amount of boil off and wort left behind decrease my overall brewhouse efficiency based on what your saying.
The boil off does not affect your efficiency to any measurable degree, because the sugars are being concentrated and not lost to the system. Leaving 0.5 gal in your kettle is a net loss of sugars and thus negatively affects your brewhouse efficiency.

When I make recipes, I use my brewhouse efficiency for the calculations because that is what is actually making it to the final packaging. So I make all of my calculation to have a net production of 5.25gal and aim for around 5.75 - 6gal in the primary. I know my losses in every vessel (tun, kettle, fermenter), an average boil off percentage for my kettle (up it a bit for cold weather), and also use standard absorption rates for the grist. I ignore the hop absorption, since I use a hop spider and can wring out a lot of that back into the kettle at the end of the boil.

With all losses in the system accounted for, you can trust the math of your recipe and know ahead of time what you should end up with. Any variation to this end and you should be able to look at your brew log and see where things were different from the normal conditions. This is why I measure every step; then you know if your second runnings should be 2.5 gal, but you only got 2 you lost some in the mash tun.

Hope that helps.
 

mthompson

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I still don't think it is a very useful calculation, despite my omission.
Usefullness is a matter of personal relevance. I find those losses relevant to my personal style of brewing, and use them in my recipe calculations. My father-in-law rarely take gravity reading much less volumes other than pre- and post boil. But, he is starting to come around.

One of his recent batches, he copied a recipe exactly out of BYO and had a OG of around 1.032 when it should have been 1.048. I looked at the recipe and used my calculations (we use essentially the same set up) and he should have had around 3-4 lbs more in his grist to hit the beer style numbers that the author had published.

Sure, it still made beer....but the beer could have been better with a few minutes of tinkering and calculating. He now at least plugs ingredients into hopville and makes sure the recipe looks right, and then uses a mash water calculator for the math.

The thing I am most proud of is, that in huge permanent marker letters, he wrote on the garage wall "Trust the Math!" (right below RDWHAHB!)
 

matalec1984

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^^^^^

I think you nailed...It's not imperative to calculate efficiency but its another opportunity for you to understand and have control over it. While not everyone is going to have interest in this particular calculation I think it can be very useful, especially like you said when trying to adapt a recipe to your specific equipment setup.
 

alestateyall

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I agree with mthompson here.

I don't know what number people here on HBT. Probably the higher number so they can brag.

Brew house efficiency is the number needed predict OG when designing a recipe.

I measure efficiency. But to me the most important question is did I hit my target OG? If I did, I did something right and I am happy. I would rather brag about hitting my OG than what my efficiency is.
 

broadbill

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Usefullness is a matter of personal relevance. I find those losses relevant to my personal style of brewing, and use them in my recipe calculations. My father-in-law rarely take gravity reading much less volumes other than pre- and post boil. But, he is starting to come around.

One of his recent batches, he copied a recipe exactly out of BYO and had a OG of around 1.032 when it should have been 1.048. I looked at the recipe and used my calculations (we use essentially the same set up) and he should have had around 3-4 lbs more in his grist to hit the beer style numbers that the author had published.

Sure, it still made beer....but the beer could have been better with a few minutes of tinkering and calculating. He now at least plugs ingredients into hopville and makes sure the recipe looks right, and then uses a mash water calculator for the math.

The thing I am most proud of is, that in huge permanent marker letters, he wrote on the garage wall "Trust the Math!" (right below RDWHAHB!)
To each their own, and I'm not saying you don't need to do any math. I'm just wondering out loud what brewhouse efficiency (as BS calculates it) tells you exactly.

From what little you told me about your FIL's recent experience, would knowing his brewhouse efficiency had helped? If so, how exactly?

For the record, I do the more dead reckoning/KISS method. I tailor my recipe so that I have 6 gallons of 1.0xx wort at the end of the boil. 6 gallons gets me to 5 gallons in the keg (with room to spare). Done.
 

mthompson

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From what little you told me about your FIL's recent experience, would knowing his brewhouse efficiency had helped? If so, how exactly?
Yes, after the fact, when I plugged the recipe he used in, using my data (similar to his) the recipe was obviously deficient in grain amounts for how we brew. Without knowing at least a starting point to look for what went wrong, it would have taken longer to figure out, and he would have just given up on that recipe. But, instead he re-brewed the recipe based on my system's numbers and he got a beer that was closer to what the author intended, and it was way better beer. This may not be a perfect example of why knowing the brewhouse efficiency is, at least helpful, for brewing.

A better example I can think of is, if you use a pump, plate chiller, kettle drain, etc. you are going to have a loss of wort in each. So, if you lose lets say 0.15 gal in three separate areas, that is 0.45 gal lost.

Simple recipe (Made this Saturday):
  • 9.0 lbs Two-row Pale
  • 2.5 lbs Vienna
  • 1.0 lbs Caramel 10

I actually ended with 6.5 gal at 1.057 and calculated at 80.46% brewhouse efficiency. This volume is what I should have ended with based on what I know I lose throughout my system.

If I did not account for losses and I ended with 6.05 gal at 1.057, that would be only 74.89% brewhouse efficiency.

I don't lose anything because I just dump my whole kettle in the fermenter. But when I get my keggle built next week, I'll lose some in the diptube/keggle and I will change my system data to reflect that. (but I will also be making 10gal batches!) Now in the scheme of things, is this going to make or break a beer? Definitely not. However, I would like to have an extra growler of beer in the keg because I took a few minutes and did some math. My FIL just uses an average efficiency and checks the recipes he makes, and his beers are more consistent because of it. (now if I could only get him to control fermentation temps and wait longer that 2-3 weeks before kegging/consuming!)
 

matalec1984

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So returning back to my initial question...

While I had a solid mash efficiency at 87.7% the fact that I boiled 7 gallons, boiled off 1.5 of it and then left another 2/3 or so behind in the kettle with trub, would hurt my overall brewhouse efficiency and OG correct?
 

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There are three distinct points in the process where efficiency can be recorded as a useful datapoint.

Mash Efficiency measures sugars derived from the grain as they currently exist in the mashing vessel. This is essentially a measure of conversion.

Mash/Lauter Efficiency takes Mash Efficiency and incorporates sugar losses in the lauter/sparge process and getting it into the boiler. In other words, any sugar left in the tun or lines leading to the kettle reduce the initial Mash Efficiency numbers.

Last, BrewHouse effeciency is net result of the brew day. How much of the theoretical sugar finally made it into your fermenter. This accounts for all losses including conversion loss, lauter loss, trub left in the kettle, and any spillage. This is by definition, the lowest number of the three. The name "brew house" should be your guide here. The mash tun, lauter tun, boil kettle, and whirlpool (not usually separate in homebrewing) are all part of the brewhouse so losses at any of those steps would be included in that figure.

I agree that people are confused, unintentionally vague, and the software all calls this stuff different things. Terms like "into the boiler" would represent Mash/Lauter Efficiency while "into the fermenter" represents Brew House.


Let's try to remember that discussions about terminology and definitions need not degrade into "who cares about efficiency?" or "consistency is more important" rhetoric. While those may be valid points, that's not what this thread was about.
 

mthompson

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So returning back to my initial question...

While I had a solid mash efficiency at 87.7% the fact that I boiled 7 gallons, boiled off 1.5 of it and then left another 2/3 or so behind in the kettle with trub, would hurt my overall brewhouse efficiency and OG correct?
Boiling off 1.5 gal does not hurt your brewhouse efficiency. You still have the same amount of sugars, they are just more concentrated.

If you leave 2/3 of a gallons behind, you are losing part of you brewhouse efficiency.
 

broadbill

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So returning back to my initial question...

While I had a solid mash efficiency at 87.7% the fact that I boiled 7 gallons, boiled off 1.5 of it and then left another 2/3 or so behind in the kettle with trub, would hurt my overall brewhouse efficiency and OG correct?
It would hurt your brewhouse efficiency (as BS calculates it), but your OG would stay the same as it was at the end of the boil.
 

matalec1984

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Makes sense with the boil off cause the sugars aren't going anywhere. if I leave behind wort in the kettle then obviously I'm not bringing those sugars with me and my efficiency and possible OG are both affected.

Thanks!!!
 

mthompson

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if I leave behind wort in the kettle then obviously I'm not bringing those sugars with me and my efficiency and possible OG are both affected.
OG should be the same, since it is a homogenous mixture and all parts are made of the same concentration.

6 gallons at 1.057 in one bucket is the same as 3 gallons at 1.057 in each of two buckets.
 

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Agree, volume loss is not efficiency loss. Efficiency is the measure of total sugar collected vs. total sugar potential of the grain. It doesn't matter if you have it dissolved in 10 gallons or 2 gallons.
 

matalec1984

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Ok, then and not to go off topic but if my mash efficiency was solid and pretty much matched my BS efficiency, what would be the most likely cause of my OG being significantly lower than expected?
 

stux

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The only reason those two numbers are different is because the volume has been reduced by a boil step. Efficiency has nothing to do with why these numbers are different. Your efficiency has already been determined by your process upstream of the boil step.
The evaporation does not affect the efficiency. Leaving trub behind in your kettle or losses in your chiller does.

Eficiency at a given stage is the percentage of potential extract from the initial grain bill present
 

mthompson

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Ok, then and not to go off topic but if my mash efficiency was solid and pretty much matched my BS efficiency, what would be the most likely cause of my OG being significantly lower than expected?
Are you measuring the volume accurately? Inaccurate volumes will change the concentration, or the SG. If you think you have 5 gallons, but you actually have 6 gallons, the efficiency is going to calculate out lower.
 

matalec1984

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Well I def had 7 gallons when I took my pre-boil grav and got 1.042.

I didn't take my SG until after I chilled and siphoned into my fermenter. It was a little past the 5 gal mark on the fermenter, right around 5 1/8 which I look to do to account for loss when racking to secondary. The gravity reading I took at this point came out to 1.052.
 

stux

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Did you let your gravity samples cool down, and then rescaled them to the calibration temperature?
 

mthompson

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How are you measuring the volume in the fermenter? If it is a bucket, did you make your own graduations based on known volumes of water that you added?

The factory marks can be off by 0.5gal or more!
 

mthompson

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Well I def had 7 gallons when I took my pre-boil grav and got 1.042.

I didn't take my SG until after I chilled and siphoned into my fermenter. It was a little past the 5 gal mark on the fermenter, right around 5 1/8 which I look to do to account for loss when racking to secondary. The gravity reading I took at this point came out to 1.052.
Also, there is a roughly 4% shrinkage from hot wort to cooled wort. So, 7gal hot is around. 6.7gal cooled. With these calculations, you need to correct everything into the same equivalents, so you have apples to apples.

Did you accurately measure the volume left behind after using your siphoned, including in the tube?
 
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