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spectre6000

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More than a decade ago, I did some extract brewing, but it didn't really scratch the itch that needed scratching. I like high gravity stouts, barleywines, and similar. I don't drink much, so when I do I'm happy to splurge for quality. Being able to have the control to get exactly what I want is great. That said, I know these sorts of beers are difficult, so I don't want to have to drink a hundred bottles of mistakes for all the attempts it's going to take to get it right (a single 5 gallon batch would easily last me a full year, and probably longer). I recently discovered BIAB brewing, and that is exactly what I needed to be able to do what I want to do! I got all the stuff, and yesterday brewed my first all grain beer. I'm brewing micro-batches of ~1 gallon. At that size, I can brew in my kitchen, bottling isn't a big PITA, ingredients are cheap, less/smaller/cheaper equipment is needed, etc., etc.

After a little googling, I landed on this as my initial recipe to explore. It's a little on the complicated side, but the 1.070 OG is on the heavier side, and thus more likely to be something I want to drink. I followed it to the letter minus the adjuncts. I had to guesstimate a bit with the hops due to lack of a sufficiently accurate scale (which I ordered in the moment, and will be on hand for the next brew). My intent is to brew it up, see how it is, and then start playing around with individual variables until I get it where I want it. Eventually, I'll get around to the adjuncts.

It mostly went off without a hitch. Actually, the whole process went much smoother than expected to the point that I was able to simultaneously bake up a loaf of spent grain bread for dinner! My one big complication is that my burner simply isn't hot enough to get a really good boil. It boiled all right, but there was zero danger of any boiling over at any point... Just enough of a boil to unquestionably be a boil, and no more. Another potential... factor, though I'm not aware of any complications that may have been caused by it, but I'm throwing it in anyway just in case, I'm at ~7K' altitude.

So the mash went off without a hitch. The recipe says to get the strike water up to 164°, which should cool to mach temp at 155° when the grains are added. I only got down to 157°. Eventually (~30 minutes) the thermometer read down at 150°, at which point I turned the burner back on to low, and stirred, but the burner likely didn't have time to have any effect, as just stirring brought it back up to 156° more or less for the rest of the mash.

This is where things start to get a little funky, and why I mentioned the above details as I did.... Upon completion of the 60 minute boil, my gravity was 1.056 (target is 1.070) and volume was much more than needed. My pot isn't marked for volume graduations (yet), but it was just clearly too much for my fermenter. I removed the hop spider, and continued boiling. At 15 minutes past the hour mark, I measured 1.064. From there, I figured I had gained .007, so another 15 minutes could get me another .007 and put me on the money... unless there was a curve to the rate, so I did another check at 10 minutes for 1.065... So the curve was getting shallower. From there I gave it the rest of that 15 minute interval plus all of the next. So at a total boil time of 1:45, I measured and got 1.076... I overshot. Higher gravity is what I'm after, and I didn't really feel like adding more water just to have to try again to get it right, so I just went with 1.076.

Even then, when I poured it into the fermenter, instead of the recipe's prescribed 1.3 gallon final volume, I got 1.5 gallons!

So, now that the mostly unnecessary backstory and slightly more necessary details have been divulged, here's the thing I can't quite figure out. I looked up the sugar potential of the grains in the recipe at the volumes used, and I got a brewhouse efficiency of 82%. I don't know if sugar potential is on the grain hoppers at the supply shop. I didn't know to look, and still don't know if that's even a thing. I looked up all the sugar potentials on a table on the internet, so this is a possible source of error, HOWEVER, that would be a pretty significant error...I think had my burner been more powerful, and I was able to get down to the expected 1.3 gal, it would be even higher (I didn't write it down, but I think it came out to 95%). There's no way I have a 95% brewhouse efficiency.

The next question (one which I may find out in a month and change) is what this prolonged boil will do. Again, I removed the hops according to the timer, so they didn't steep any longer, but whatever was in the wort had plenty of time to do things during the subsequent 45 extra minutes of (mild) boil. What effect, if any, will this have on the finished beer?

The final question is how to adjust for the next attempt. If I start with a lower strike volume, will that reduce my mash efficiency? Should I treat the problem where it is (the boil) and give my boil a 30 minute head start at volume reduction before starting the hop schedule? Is it even something worth addressing? If the extended boil doesn't hurt anything, it's just an extra step to do at the end..
 

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So the mash went off without a hitch. The recipe says to get the strike water up to 164°, which should cool to mach temp at 155° when the grains are added. I only got down to 157°. Eventually (~30 minutes) the thermometer read down at 150°, at which point I turned the burner back on to low, and stirred, but the burner likely didn't have time to have any effect, as just stirring brought it back up to 156° more or less for the rest of the mash.
The beer is going to be less fermentable mashing warmer so it may finish up a little sweeter than called for.
This is where things start to get a little funky, and why I mentioned the above details as I did.... Upon completion of the 60 minute boil, my gravity was 1.056 (target is 1.070) and volume was much more than needed. My pot isn't marked for volume graduations (yet), but it was just clearly too much for my fermenter. I removed the hop spider, and continued boiling. At 15 minutes past the hour mark, I measured 1.064. From there, I figured I had gained .007, so another 15 minutes could get me another .007 and put me on the money... unless there was a curve to the rate, so I did another check at 10 minutes for 1.065... So the curve was getting shallower. From there I gave it the rest of that 15 minute interval plus all of the next. So at a total boil time of 1:45, I measured and got 1.076... I overshot. Higher gravity is what I'm after, and I didn't really feel like adding more water just to have to try again to get it right, so I just went with 1.076.
It's a good idea to have a recipe file, or use brewing software, so that you know your target preboil gravity. It's a lot easier to make adjustment before the boil rather than after or in the middle of it.
Even then, when I poured it into the fermenter, instead of the recipe's prescribed 1.3 gallon final volume, I got 1.5 gallons!

So, now that the mostly unnecessary backstory and slightly more necessary details have been divulged, here's the thing I can't quite figure out. I looked up the sugar potential of the grains in the recipe at the volumes used, and I got a brewhouse efficiency of 82%. I don't know if sugar potential is on the grain hoppers at the supply shop. I didn't know to look, and still don't know if that's even a thing. I looked up all the sugar potentials on a table on the internet, so this is a possible source of error, HOWEVER, that would be a pretty significant error...I think had my burner been more powerful, and I was able to get down to the expected 1.3 gal, it would be even higher (I didn't write it down, but I think it came out to 95%). There's no way I have a 95% brewhouse efficiency.
This is another thing that software would help with. Most of the grain data is pre loaded. No, it's not possible to get 95% brewhouse efficiency on a 1.070 no sparge brew.
The next question (one which I may find out in a month and change) is what this prolonged boil will do. Again, I removed the hops according to the timer, so they didn't steep any longer, but whatever was in the wort had plenty of time to do things during the subsequent 45 extra minutes of (mild) boil. What effect, if any, will this have on the finished beer?
Removing hops does not negate any future bittering because the oils leave the hops and dissolve into the wort. Hops that were supposed to boil for 60 minutes will not add anymore bitterness. The hops added at the prescribed 30 minutes and end of boil turned into 60 minute additions also. The result is much more bitterness.
The final question is how to adjust for the next attempt. If I start with a lower strike volume, will that reduce my mash efficiency? Should I treat the problem where it is (the boil) and give my boil a 30 minute head start at volume reduction before starting the hop schedule? Is it even something worth addressing? If the extended boil doesn't hurt anything, it's just an extra step to do at the end..
Yes, start with a little less water. Your boil off rate was much lower than the average/what the recipe expected. Extracting more wort from the mash and boiling it down longer is one way to get higher brew house efficiency, but most would just scale up the grain bill a bit and stick to a 60 minute boil.
 

AlexKay

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Small batch BIAB is a great way to really get into things. Congrats on your first all-grain brew!

My feeling is that when you’re starting out, don’t worry about hitting a specific OG (or FG) or volume or whatever. A beer you’d planned as 1.070 will taste fine at 1.080 or even 1.060 — maybe not exactly what you had in mind, but if ingredients and process are solid, the beer will taste good.

Record everything — every detail — so you know how to repeat it, and pretty quickly you’ll get a good idea of how much grain and how much water you need to get the results you want. Software is nice if you’re so inclined, but also not a necessity.

Ditto mash temperature: don’t worry overmuch about keeping it constant, which is challenging for small batches anyway. Just record what you’ve got, and correlate that to how the beer comes out.

Taste, aroma, and bitterness all depend on timing for hops — how long are the relevant compounds in the boiling water? — so if you’re planning an extended boil, try to extend it at the beginning, and then keep to your planned hop schedule.

At your altitude boiling temperature is lower, which means you’re less able to convert and then drive off DMS. If you notice a vegetal, canned-corn smell or taste, that’ll be where you start looking for solutions. If you don’t (and you may not in big, malty beers) no need to worry about it.

Oh, and don’t worry about finding recipes specifically for small batches. A five-gallon recipe scaled down by a factor of 4 or 5 in all ingredients will work just fine. Though remember that you need a lot of yeast for your high gravity beers.
 
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spectre6000

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The beer is going to be less fermentable mashing warmer so it may finish up a little sweeter than called for.
Not the worst problem to have given the hop situation.
It's a good idea to have a recipe file, or use brewing software, so that you know your target preboil gravity. It's a lot easier to make adjustment before the boil rather than after or in the middle of it.
That would have been a good datapoint to have. First brew in more than a decade, and first ever AG, so I didn't know that was a critical statistic. Going forward, definitely something to look for.
This is another thing that software would help with. Most of the grain data is pre loaded. No, it's not possible to get 95% brewhouse efficiency on a 1.070 no sparge brew.
Software is obviously a good idea. Rather than try to figure out the software at this first step, I thought it made sense to use someone else's recipe to take any guesswork out. Then run THAT through the software as a means of learning it. Meanwhile, this seems to contradict the final statement in your reply. If boiling down the wort to increase gravity is a way to increase efficiency, shouldn't >100% be possible?
Removing hops does not negate any future bittering because the oils leave the hops and dissolve into the wort. Hops that were supposed to boil for 60 minutes will not add anymore bitterness. The hops added at the prescribed 30 minutes and end of boil turned into 60 minute additions also. The result is much more bitterness.
What I was afraid of/suspected. Hopefully the extra sweetness from the high mash temp helps offset it a little. More likely, it'll just be kinda crap. Fortunately, there's only 1.5 gallons of it if it's really foul.
Yes, start with a little less water. Your boil off rate was much lower than the average/what the recipe expected. Extracting more wort from the mash and boiling it down longer is one way to get higher brew house efficiency, but most would just scale up the grain bill a bit and stick to a 60 minute boil.
My concern here is whether or not starting with less water mean less sugar extracted in the mash? If I'm to calculate my brewhouse efficiency according to where the OG was at the 60 minute mark, my efficiency is at the bottom of the "normal" range from what I was able to find (62% from memory). That would indicate a different problem...
 
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spectre6000

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Small batch BIAB is a great way to really get into things. Congrats on your first all-grain brew!
Thanks!
My feeling is that when you’re starting out, don’t worry about hitting a specific OG (or FG) or volume or whatever. A beer you’d planned as 1.070 will taste fine at 1.080 or even 1.060 — maybe not exactly what you had in mind, but if ingredients and process are solid, the beer will taste good.
It's definitely more art, but science is creeping in. I'm hoping to take advantage of it.
Record everything — every detail — so you know how to repeat it, and pretty quickly you’ll get a good idea of how much grain and how much water you need to get the results you want. Software is nice if you’re so inclined, but also not a necessity.
I have the recipe to hand, but I noted every little deviation and minor hiccup as I went. There are multiple easy and obvious improvements that will be made for the second attempt, even just recreating the same recipe.
Ditto mash temperature: don’t worry overmuch about keeping it constant, which is challenging for small batches anyway. Just record what you’ve got, and correlate that to how the beer comes out.
Knowing that the recipe called for a higher temp than I usually see (and knowing what that means for the end product), I wasn't all that worried about the drop, but didn't want it to drop further. For my tastes/preferred styles, I'd probably want a higher mash temp anyway. I was surprised at how steady it stayed throughout the hour long mash.
Taste, aroma, and bitterness all depend on timing for hops — how long are the relevant compounds in the boiling water? — so if you’re planning an extended boil, try to extend it at the beginning, and then keep to your planned hop schedule.
Definitely. It's winter, and altitude, which typically means water evaporates much faster than expected. I was very surprised that the evaporation was so minimal. My inability to get a really fast rolling boil is the obvious culprit.
At your altitude boiling temperature is lower, which means you’re less able to convert and then drive off DMS. If you notice a vegetal, canned-corn smell or taste, that’ll be where you start looking for solutions. If you don’t (and you may not in big, malty beers) no need to worry about it.
Good to know. Water boils at 198°F here. I wonder if other critical temperatures decrease in a similar manner...
Oh, and don’t worry about finding recipes specifically for small batches. A five-gallon recipe scaled down by a factor of 4 or 5 in all ingredients will work just fine. Though remember that you need a lot of yeast for your high gravity beers.
Right. I found that recipe at some point in my preparatory research, and it sounded good enough (from what I could tell). I took note that the yeast packet said to use 3 packs for beer above (some) gravity for a 5 gallon batch. The one package I had worked out to slightly more than that (another advantage of the small volume), so I just went with it. I'm thinking hard about trying to recover some of the yeast when I'm done as well. Haven't looked into that yet; plenty of time to do so.
 

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Thanks!

It's definitely more art, but science is creeping in. I'm hoping to take advantage of it.

I have the recipe to hand, but I noted every little deviation and minor hiccup as I went. There are multiple easy and obvious improvements that will be made for the second attempt, even just recreating the same recipe.

Knowing that the recipe called for a higher temp than I usually see (and knowing what that means for the end product), I wasn't all that worried about the drop, but didn't want it to drop further. For my tastes/preferred styles, I'd probably want a higher mash temp anyway. I was surprised at how steady it stayed throughout the hour long mash.

Definitely. It's winter, and altitude, which typically means water evaporates much faster than expected. I was very surprised that the evaporation was so minimal. My inability to get a really fast rolling boil is the obvious culprit.

Good to know. Water boils at 198°F here. I wonder if other critical temperatures decrease in a similar manner...

Right. I found that recipe at some point in my preparatory research, and it sounded good enough (from what I could tell). I took note that the yeast packet said to use 3 packs for beer above (some) gravity for a 5 gallon batch. The one package I had worked out to slightly more than that (another advantage of the small volume), so I just went with it. I'm thinking hard about trying to recover some of the yeast when I'm done as well. Haven't looked into that yet; plenty of time to do so.
The chemical reactions going on in the mash and the boil depend on temperature. You’d ideally use the same temperatures as everyone else, but you can’t get the boil as hot as you could at sea level — hence the problem. DMS is the big worry (especially if your boil is not vigorous), though alpha acid isomerization (to produce bitterness) will be slower as well.

Yep, never needing to make a starter is one of the advantages of small batches!

You usually don’t reuse yeast after a particularly big beer — it’s already stressed. You could overbuild a starter and then save it for future batches; that’ll probably give better results.
 

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I looked up the sugar potential of the grains in the recipe at the volumes used, and I got a brewhouse efficiency of 82%. I don't know if sugar potential is on the grain hoppers at the supply shop...I think had my burner been more powerful, and I was able to get down to the expected 1.3 gal, it would be even higher (I didn't write it down, but I think it came out to 95%). There's no way I have a 95% brewhouse efficiency.

Just a comment on this. 82% brewhouse efficiency is not out of the question. Given your long boil and extra volume, that meant you were using more initial volume of water than planned. That will help with efficiency. It could also be due to measuring errors. At the 1 gallon batch size, a few ounces of volume has a big impact. Are you able to get an exact reading on the volume into the fermenter?

But...boiling more will not increase your brew house efficiency. You will still have the exact same amount of sugar (gravity points) in the final batch after boiling. Boiling just removes water and concentrates the sugars, so you have a higher gravity and a lower volume. The opposite would be adding water to the beer. That also does not change your efficiency, but just increases volume and reduces gravity.
 

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Software is obviously a good idea. Rather than try to figure out the software at this first step, I thought it made sense to use someone else's recipe to take any guesswork out. Then run THAT through the software as a means of learning it.
When it comes to all grain recipes, there are so many varying techniques and system designs that the recipe is much more of a spec sheet than instructions. The recipe designer doesn't know your mash efficiency, your boil off rate or any other volume losses in your system. The typical way this is done is that you input as much info as you know into a software's equipment profile. Then when you import a recipe, you immediately change to your equipment profile and allow the recipe to scale to meet your system. New all grain brewers often post questions like "Why didn't I hit my numbers?". In reality, they didn't hit the recipe designers numbers and efficiency is the main driver for that.
Meanwhile, this seems to contradict the final statement in your reply. If boiling down the wort to increase gravity is a way to increase efficiency, shouldn't >100% be possible?
No. To get 100% efficiency, you would have to leave zero sugar behind in the damp grain. Wort has a certain sugar density and some wort stays in the grain.
My concern here is whether or not starting with less water mean less sugar extracted in the mash?
It goes like this: The more water you use, the lower the gravity of that wort will be. That means the wort absorbed by the grain (a fixed volume) will have less of the batch's sugar trapped. You get a higher brew house efficiency at the cost of a longer boil time to concentrate to a usable volume. This is an issue of diminishing returns. For example, boil for 60 minutes or boil for 3 hours and save 20% of your grain cost? How much is your time and fuel worth?

A typical brewhouse efficiency for BIAB is about 65-75% for an average gravity 5 gallon batch. Smaller batches will go up from there due to the ease of squeezing the bag. The higher the recipe's OG, generally the lower the efficiency is.
 
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spectre6000

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Yeah... first time through, I don't know what my numbers are to be able to do any such adjustments. Kinda winging it and using the first few brews to get the process figured out in the first place.

One of the critical questions that has arisen from my first round is mash volume. I can't get a hard enough boil to hit my final volume targets, and with such a small batch, as has been pointed out, it's pretty easy to get most of the wort squeezed out of the bag. I'm unclear on whether or not reducing the mash volume will reduce the amount of extracted sugars, or if it's better to just have a 30 minute pre-boil. I have a gas stove, and as far as I'm concerned, the fuel cost is negligible (small batches ftw!). If I reduce the strike water volume, will I also reduce the amount of sugars extracted from the grain, assuming everything else remains the same?

Is there anyone at altitude that can chime in with this? I get lower temperatures, but I honestly can't think of a single cooking related issue I've run into with the water temp dropping, and whatever related enzymatic action not dropping accordingly. Yes, the temperature is lower, but so is vapor pressure, and the water is moving at the same rate at the molecular level, etc. The temperatures for most things seems to change along with the boiling temp.

Clarification needed.... Brewhouse efficiency is calculated by potential sugars in the grain vs. OG post-boil. I did a fair amount of digging about how to calculate it, and in none were boil time considered. It is a measurement of the efficiency of equipment and process. A long boil would be part of the process, and thereby part of the "brewhouse", correct? Even if you add water right at the end of the boil to get OG down, that would still be included in the calculation, right? The only way the boil isn't considered is if the OG reading is done pre-boil, which doesn't make sense for obvious reasons. Just trying to wrap my head around this one, since it seems so critical for figuring out things like strike water volume, which may be a critical parameter I need to adjust here...
 

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Clarification needed.... Brewhouse efficiency is calculated by potential sugars in the grain vs. OG post-boil.
It also factors in volume. You could create 5 gallons of 1.050 wort with the same efficiency as 2.5 gallons of 1.100 wort or 10 gallons of 1.025. All of these examples have 250 gravity points (5 x 50 = 250, 2.5 x 100 = 250, 10 x 25 = 250). In order to calculate any efficiency values you need both accurate gravity and volume measurements. Adding water or boiling off water does not change the efficiency, just the volume and gravity.
 

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If you’re really invested in this, I’d recommend downloading a brewing software program. Everyone uses different ones (BeerSmith, Brewer’s Friend, etc.). Some are free, some have a smallish initial purchase price. You create your own equipment profiles specific to your situation and then when you input all the variables for your recipe, the program spits out relatively accurate datapoints and information for your batch. One important thing you need to determine is what’s called your “boil off” rate. That is an important number that determines what your mash water volumes will be.
Good luck on your future brews.
 

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Since you’re doing small batches, a couple ways to stabilize your mash temperatures are—
1. Cover your kettle with a heavy blanket or sleeping bag or a few bath towels.
2. Some folks preheat their oven to the lowest setting then shut it off. Place your kettle in there for the duration of the mash.
 

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One of the critical questions that has arisen from my first round is mash volume. I can't get a hard enough boil to hit my final volume targets, and with such a small batch, as has been pointed out, it's pretty easy to get most of the wort squeezed out of the bag. I'm unclear on whether or not reducing the mash volume will reduce the amount of extracted sugars, or if it's better to just have a 30 minute pre-boil. I have a gas stove, and as far as I'm concerned, the fuel cost is negligible (small batches ftw!). If I reduce the strike water volume, will I also reduce the amount of sugars extracted from the grain, assuming everything else remains the same?
I'm probably not explaining it in terms you understand yet, but I think I covered it. Yes, the total sugar you extract from the grain goes up as your mash is more dilute and that is explained by the lower concentration of sugar in the fixed volume of wort that you can't get out of the grain no matter how hard you squeeze. An exaggerated example: Let's say the amount of grain you use holds on to one pint of liquid after a hard squeeze. If you start one batch with 1 gallon of mash water with and end up with 1.050 SG then you could also do it with 2 gallons and the SG would be 1.025. The mash derives the same amount of sugar into solution, but batch one loses one pint of 1.050 wort while the second one loses a pint of only 1.025 SG wort. The diminishing returns comes in when considering how long it would take to boil off that whole extra gallon.

Practical advice, stick to 60 minute boils for anything without Pilsner malt and 90 minute boils for anything that has Pilsner malt (high in DMS precursor).
Clarification needed.... Brewhouse efficiency is calculated by potential sugars in the grain vs. OG post-boil. I did a fair amount of digging about how to calculate it, and in none were boil time considered. It is a measurement of the efficiency of equipment and process. A long boil would be part of the process, and thereby part of the "brewhouse", correct? Even if you add water right at the end of the boil to get OG down, that would still be included in the calculation, right? The only way the boil isn't considered is if the OG reading is done pre-boil, which doesn't make sense for obvious reasons. Just trying to wrap my head around this one, since it seems so critical for figuring out things like strike water volume, which may be a critical parameter I need to adjust here...
Efficiency is basically grain weight x grain PPG divided by volume. In a full volume, no sparge mash, if you measure the gravity and volume post mash, pre-boil, you're calculating Mash/Lauter Efficiency, i. e. how well did you convert starches to sugars and separate the sugars from the spend grain. If you measure gravity and volume in the fermenter, you're getting the entire brewhouse efficiency and that accounts for losses of volume in the boil kettle to trub, if one were to leave volume behind there. None of the measurements actually care about the boil length or boil off rate as you just have to get used to how much you boil off and integrate that into your starting water volume.
 
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spectre6000

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Efficiency is basically grain weight x grain PPG divided by volume.
For clarity, volume of what? Post-boil wort is what I understood and used in my calculation.

I will be figuring out a software solution in the near future, but I need to figure out my system first since they all need system information (like efficiency) I don't have without a few test runs.

2. Some folks preheat their oven to the lowest setting then shut it off. Place your kettle in there for the duration of the mash.
My oven has a "dehydrate" function that keeps it at 150°. Seems about perfect for holding mash temp!

I started with something like 10 liters (in imperial units, there's a rounding error in the difference between the last 1/4 and 1/3 cup), and ended up with 1.5 gallons after a 1:45 boil. My tun doesn't have volume marks (yet), so I don't know the exact, or really even approximate, volumes at any other given times. Given the assumptions that the grain held .17 gallons (napkin math to get it to 2.5 for roundish number purposes), and I'm .2 gallons over my 1.3 gallon target, my approximate boil off rate should be in the neighborhood of 2/3 gallons/hour. Therefore, my target should be on the order of 2 gallons strike water even for the next attempt. Seem like a recipe for success?
 

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For clarity, volume of what? Post-boil wort is what I understood and used in my calculation.
It was in the next couple sentences:
....... if you measure the gravity and volume post mash, pre-boil, you're calculating Mash/Lauter Efficiency, i. e. how well did you convert starches to sugars and separate the sugars from the spend grain. If you measure gravity and volume in the fermenter, you're getting the entire brewhouse efficiency and that accounts for losses of volume in the boil kettle to trub, if one were to leave volume behind there.
My oven has a "dehydrate" function that keeps it at 150°. Seems about perfect for holding mash temp!
Can't beat that!
I started with something like 10 liters (in imperial units, there's a rounding error in the difference between the last 1/4 and 1/3 cup), and ended up with 1.5 gallons after a 1:45 boil. My tun doesn't have volume marks (yet), so I don't know the exact, or really even approximate, volumes at any other given times. Given the assumptions that the grain held .17 gallons (napkin math to get it to 2.5 for roundish number purposes), and I'm .2 gallons over my 1.3 gallon target, my approximate boil off rate should be in the neighborhood of 2/3 gallons/hour. Therefore, my target should be on the order of 2 gallons strike water even for the next attempt. Seem like a recipe for success?
Sounds like a good place to start the next one.
 
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spectre6000

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It was in the next couple sentences:
....... if you measure the gravity and volume post mash, pre-boil, you're calculating Mash/Lauter Efficiency, i. e. how well did you convert starches to sugars and separate the sugars from the spend grain. If you measure gravity and volume in the fermenter, you're getting the entire brewhouse efficiency and that accounts for losses of volume in the boil kettle to trub, if one were to leave volume behind there.
Right. Pre-boil is mash/lauter efficiency (good to know, are there typical figures for that?). Post-boil is brewhouse efficiency, but "boil" (and any water additions that occur between mash and post-boil) seem to not be accounted for... Right? So if I add a TON of water, I could have a 0% efficiency through dilution. If I boil forever to where I end up with essentially malt extract, I can have well over 100% efficiency. Is "boil" required in this equation to have no additions and be exactly 60 minutes? OR is "boil" what you want it to be for your typical process maybe? So 60 minutes being typical for hop schedules, and no one really wants to have to adjust one way or the other to hit target numbers, and that's "boil" for these purposes?

If I understand correctly, brewhouse efficiency is probably somewhat moot until I nail down a process that I like... So I need to brew a few more times to settle in on something, and THEN calculate to see where I'm at for the purposes of software.
 
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CascadesBrewer

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If I understand correctly, brewhouse efficiency is probably somewhat moot until I nail down a process that I like... So I need to brew a few more times to settle in on something, and THEN calculate to see where I'm at for the purposes of software.
There is no reason that you have to have everything nailed down and manually calculate your efficiency before using software. I would say it is the opposite. Find some software that you seem to like and learn how to use that software to calculate you efficiency values.

Also, different software use different definitions of brewhouse efficiency (or "overall efficiency"...or just "efficiency"). In some cases this is the amount at the end of the boil, and in some cases this is the amount into the fermenter.

Plugging values into software might help you realized that, no adding water will not bring your efficiency down to 0% and boiling will not bring your efficiency up to 100%. Your mash efficiency will set the upper limit for your brewhouse efficiency. If you get 85% mash efficiency, then just dump the entire contents into your fermenter you will be at 85% brewhouse efficiency. If you lose some amount of wort (say to hop absorption, trub left in the kettle, wort in transfer hoses, amount for a gravity reading, etc.) you will have an overall efficiency that is a bit lower than your mash efficiency. Boiling just removes water, and does not impact your efficiency. It just concentrates the sugars that you were able to extract from the grains.
 

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Post-boil is brewhouse efficiency,
There is some debate about exactly where this is measured. In "Brewfather" software for example, you have to select between "end of boil" and "into the fermenter" where the latter accounts for trub loss in the kettle.

but "boil" (and any water additions that occur between mash and post-boil) seem to not be accounted for... Right? So if I add a TON of water, I could have a 0% efficiency through dilution.
No. If you have a gallon at 1.050 after the mash (let's assume you got 80% of the sugars out of the grain) and you add 49 more gallons of water you have 50 gallons at 1.001. Your efficiency is exactly the same 80%. The efficiency calculation operates in complete disregard for how much volume you actually want to end with.

If I boil forever to where I end up with essentially malt extract, I can have well over 100% efficiency.
Also false. In the above example, if you took that gallon of 1.050 and boiled it down to one quart, you have one quart at 1.200 gravity and it's the same efficiency (80% is what we supposed).
OR is "boil" what you want it to be for your typical process maybe? So 60 minutes being typical for hop schedules, and no one really wants to have to adjust one way or the other to hit target numbers, and that's "boil" for these purposes?
Correct.
If I understand correctly, brewhouse efficiency is probably somewhat moot until I nail down a process that I like... So I need to brew a few more times to settle in on something, and THEN calculate to see where I'm at for the purposes of software.
Software does a myriad of things and one of them is to have a place to record your actual results. It will tell you what your efficiencies actually were so you can pop that number into your equipment profile. The next time you brew, you'll be closer to your expected numbers. If not, you enter those new numbers into the profile. Each time you brew you get closer and closer until you're nailing the numbers pretty well. That's both target gravity and fermenter volumes. I'm not saying you absolutely have to jump on board, but the two popular platforms are Beersmith 3 and Brewfather. Either is $20 A YEAR or less. You might as well be in the weeds with a little framework.

They also have tools for if you overshoot or undershoot to help you decide how much water to top off, how much longer you'd need to boil to concentrate, how much DME to add, etc.
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spectre6000

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Well... Today was bottling day. Went well for the most part. First time means figuring out equipment and such, and my bottling wand setup refused to stay connected to the spout such that I ended up having to just fill the bottles slowly and at an angle to minimize oxygenation. Hopefully it'll be fine.

The next round of inquiry is in regard to yeast attenuation. I checked the final gravity at the end, and it read 1.047! The recipe states the target is 1.021, so I'm pretty high. ABV works out to 6.00%, which doesn't seem terrible. It'll be pretty average ABV and slightly sweet. Still, what's up with the low yeast attenuation? Fermenter lived in our pantry, which is partially underground and a very stable 68°. It gets opened a few times a day re: light, and there shouldn't be much in the way of physical disturbance. The yeast went pretty crazy the first day, and I probably should have known to set it up initially with a blow off tube. I ended up cleaning the overflow up a few times that day to keep it from getting too bad, and swapped the airlocks (quickly and starsanned) since they were full of wort rather than starsan. Still don't think that would necessarily cause the yeast to just give up halfway through...
 
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spectre6000

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I didn't try to connect the wand directly to the spigot. There were two different sizes of tubing and an adapter in the middle. When dry, it works. When wet with sanitizer, it slides right off. Spigot is too fancy and shapely.

Read FG with refractometer, and ran the numbers through the various calculators (refractometer correction w/ alcohol, and ABV).
 

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That depends on the spigot. My bottle wand fits very well on the spigot that came with my bottling bucket. The spigots on my Vintage Shop PET fermenters, not so much.
 
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spectre6000

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I have a glass Little Big Mouth Bubbler, and the stainless spigot that comes with it. If there was a spigot that would work with that AND could directly connect a bottling wand (or at least was the same OD to where it could be connected with just a short bit of tubing), I'd be all over that.

EDIT: Thinking about this beyond the initial reaction (above), the LBMB can easily hang off over the edge of the counter to get the job done. That last bottle or two requires tipping it up, so an inch or so of intermediate tubing to allow for some flex would be required.
 
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spectre6000

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I misspoke... The refractometer directly read 1.047. I didn't write down what that worked out to post-correction. The 6.00% ABV was the final number with everything corrected though.

The recipe mash temp was 155°, and I think I was at 157*. Is 2° enough for that much of a difference?
 

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