Constantly have low gravity
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There is a better, small batch alternative to fly sparging: Batch sparging. There are quite a few variants on that theme.
BIAB (Brew/Mash In A Bag/Basket) used with most single vessel brew "systems" is basically a non-sparge variant, or a (small) dunk sparge (or two) can be added at the end for increased efficiency, but require a second vessel large enough to hold the grain bag and some additional (sparge) water.
Going the batch sparge route doesn't obsolete your investment in equipment, it uses it more efficiently:
- Your HLT (converted round cooler) remains your hot water storage vessel.
- Your Mash Tun (converted round cooler) remains your mash tun. There are a few ways to incorporate the false bottom. Or use a mesh bag as the filter instead.
- Your boil kettle remains what it is, your boil kettle. Just watch your boil-off (evaporation) rate, it tends to be much higher with oversized kettles, as in 2-3x as high. For example, 2 or 3 gallons boil off per hour instead of only one. Depends on your heat source too.
In this BIAB scenario, your boil kettle becomes more or less a single vessel type of brewing "system." The HLT can still store your pre-heated sparge water, while your mash tun has become the sparge vessel.
Nevermind, was replying before a page refresh showed many more posts covering what I was going to say.
But since I'm here, I'll mention that this could be a "back to the basics" opportunity.
X lbs grain, ensure a good crush
predetermined water amount to mash in
temp for that water before mashing, to be sure it'll be OK when actually mashing
batch sparging with instructions as to water used
Shouldn't be terribly hard to get a reasonable gravity from that. We'd all be willing to take a look at the numbers.
But since I'm here, I'll mention that this could be a "back to the basics" opportunity.
X lbs grain, ensure a good crush
predetermined water amount to mash in
temp for that water before mashing, to be sure it'll be OK when actually mashing
batch sparging with instructions as to water used
Shouldn't be terribly hard to get a reasonable gravity from that. We'd all be willing to take a look at the numbers.
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i actually read this thread, you did mill the grain right? not to ask a stupid question but out of curiosity?
edit: except the last post! @tracer bullet
edit: except the last post! @tracer bullet
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So your statement is tied to what you consider a "small batch system" in that you are considering it in the context of BIAB. The OP has a three vessel system. I don't particularly see any impracticality of fly sparging between say a 5, 10, or 15 gallon three vessel system, which are like small, medium, and large for homebrewers. It'll take a little longer sure but that's not impractical. I wouldn't have to change my sparge arm, it's just working with different volumes.
Batch sparging is easier but less efficient. Fly sparging can be somewhat tedious to fool around with your pump and valves at times. It's not impractical though. I started out all grain brewing where I mashed on the stove and transferred to a lauter tun built from a plastic brewing bucket with drain holes drilled inside a bottling bucket. I used a small 1-2 gallon bucket also with holes to fly sparge the water into the lauter tun. Tedious but not impractical.
I'm not particularly keen to make it a BIAB vs 3 vessel type argument, but if I am reading you correctly, you've had to add another vessel just to sparge in your description. Basic BIAB you aren't really sparging in the first place, not as we are discussing.
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I'm not leaning towards you have a sparging problem unless you had channeling perhaps. Your recipe would have an estimated original gravity somewhere close to 1.070 for a five gallon batch. If your measured value for the original gravity is 1.020, that is grossly off from the estimate. Thirty minutes of sparge time for 3.2 gallons is nowhere near too fast. Do you have some sort of sparge arm that diffuses the water over the grain bed? I suppose it's possible that you could have created a channel if you were pouring the water into the MT with say a pitcher and kept pouring it at the exact spot but to do that over multiple batches, seems unlikely that's the problem. Your temps were fine, even fading lower isn't an issue because in that range that you dropped, that would tend to increase the final ABV. Since you had two thermometers, less likely your temperatures were grossly off.
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I hope you figure this out. Im newer to homebrewing and have not experienced this issue but can tell you it isn't distilled water making your numbers bad. However I did my first AG batch with distilled water and no water chemistry and the numbers were good but it tasted grainy I think from ph inbalanced. For this reason I would advise not using distilled water unless you moniter and correct ph. Good luck
BrewnWKopperKat
ʘ‿ʘ
Take a look at "Water Chemistry - How to Build Your Water" (link). The adjustments for brewing with RO/distilled water are not complicated and don't need a pH meter.
SRJHops
Why did the rabbit like NEIPA's so much?
A good puzzle... I am guessing your expected OG was around 1.060 or so, so getting 1.020 is indeed shockingly low.
Seems the two most likely issues, as noted by others, are gravity measuring issues and the use of distilled water.
Distilled water alone is not a great source for brewing water. The starting ph is 7, and you'll likely not end up with an ideal mash ph between 5.2 and 5.6. You'll also be missing some key nutrients for fermentation, such as calcium. Unless it's totally awful, you'd be much better off using tap water and a campden tablet.
The thing is, people who don't adjust their mash water ph still get better conversion than you are getting, even with tap water in the 9 ph range. So, I think measuring issues must be in play here too.
There seemed to be some discussion about what you are measuring. It should of course be the wort in the kettle (stirred gently to mix), both pre and post-boil. (Or the wort in the fermenter before adding yeast.) Keep in mind that all measuring tools have trouble with high temperatures, even when they claim to adjust. So try to measure at room temperature.
I actually measure OG three ways, and it's a good day when all three measuring tools are in agreement! I use a refractometer, hydrometer, and Tilt. When they don't agree, I usually defer to the hydrometer, which needs the least calibration.
Seems the two most likely issues, as noted by others, are gravity measuring issues and the use of distilled water.
Distilled water alone is not a great source for brewing water. The starting ph is 7, and you'll likely not end up with an ideal mash ph between 5.2 and 5.6. You'll also be missing some key nutrients for fermentation, such as calcium. Unless it's totally awful, you'd be much better off using tap water and a campden tablet.
The thing is, people who don't adjust their mash water ph still get better conversion than you are getting, even with tap water in the 9 ph range. So, I think measuring issues must be in play here too.
There seemed to be some discussion about what you are measuring. It should of course be the wort in the kettle (stirred gently to mix), both pre and post-boil. (Or the wort in the fermenter before adding yeast.) Keep in mind that all measuring tools have trouble with high temperatures, even when they claim to adjust. So try to measure at room temperature.
I actually measure OG three ways, and it's a good day when all three measuring tools are in agreement! I use a refractometer, hydrometer, and Tilt. When they don't agree, I usually defer to the hydrometer, which needs the least calibration.
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Whats your grain crush like? Whats your mash ph? Did you check if your thermometer is accurate? Are you using correct water volumes? Sort those things out and next batch yoy will definitely see a better target OG, 12 lbs of grain fot 5 gallon batch should definitely yield a 1060 OG, best of luck to ya
Yes, a correctly done fly sparge has higher lauter efficiency (and thus higher mash efficiency) than a batch sparge. However, it is much simpler for a beginner to get good and consistent results with a batch sparge, since channeling is not a possibility. All that is required is aggressive mixing prior to each run-off. With where the OP is in their learning, batch sparging is probably a good option until they can get consistent mash efficiency.
No sparge is even simpler than batch sparge, but takes a 8% - 9% hit on lauter efficiency (and mash efficiency) compared to single batch sparge (all else being equal.)
For a beginner, maximizing efficiency should not be the goal. Learning the process should be.
Brew on
Dont sparge, it’s not necessary, i sparged 99% of my brewing life 15 years and just recently started no sparge exclusively, i like the wort/ beer more, sparge and save few extra minimal bucks or dont sparge and save time its on you
Edit: i will start sparging simply to partygyle but other then that skip it
Edit: i will start sparging simply to partygyle but other then that skip it
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If you measured the SG of the wort as you were sparging, that is very likely the cause of your low reading. The wort gets more diluted (lower SG) the further you get into the sparge process. To get an accurate pre-boil SG, you need to stir very aggressively prior to taking the measurement, so that all of the wort is homogenized (uniform sugar concentration and SG.)
To really understand your process (w.r.t. efficiency and SGs), you need to take the following measurements:
- Grain bill weight, and weighted average grain potential.
- Strike (mash) water volume, and temp at which volume is measured (for expansion correction)
- SG of wort at the end of mash (before sparging starts and after thorough mixing.)
- Pre-boil volume, and temp at which volume is measured
- Pre-boil SG, after thorough mixing and corrected for temperature
- Post-boil volume, and temp at which volume is measured
- Post-boil SG (i.e. OG), after thorough mixing and corrected for temperature
Brew on
SRJHops
Why did the rabbit like NEIPA's so much?
If you measured the SG of the wort as you were sparging, that is very likely the cause of your low reading. The wort gets more diluted (lower SG) the further you get into the sparge process. To get an accurate pre-boil SG, you need to stir very aggressively prior to taking the measurement, so that all of the wort is homogenized (uniform sugar concentration and SG.)
To really understand your process (w.r.t. efficiency and SGs), you need to take the following measurements:
Measurement accuracy is important, because the calculated values can only be a accurate as your least accurate measurement.
- Grain bill weight, and weighted average grain potential.
- Strike (mash) water volume, and temp at which volume is measured (for expansion correction)
- SG of wort at the end of mash (before sparging starts and after thorough mixing.)
- Pre-boil volume, and temp at which volume is measured
- Pre-boil SG, after thorough mixing and corrected for temperature
- Post-boil volume, and temp at which volume is measured
- Post-boil SG (i.e. OG), after thorough mixing and corrected for temperature
Brew on
I'd be curious to learn how some of those measurements really matter. My pre-boil is usually 7 gallons. And post boil I am happy with 6 gallons or so. How much could the temperature of either matter overall? Maybe for a big system, but at the homebrew level? An ounce or two? I am shooting for 5.5 gallons into the fermenter, but it's give or take a few pints to be sure.
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4% of 6-7 gallons between room temp and boiling temp. That is 30-35 ounces.
SRJHops
Why did the rabbit like NEIPA's so much?
Interesting. So maybe 2 pints. Still not sure what I would do with that info. I suppose shoot for a pint over 7 gallons for pre-boil if I really need exactly 7 gallons. (Though I don't really need to be that precise.) My wort pre-boil is around 150, give or take. If it's at 7 gallons, I wonder how many ounces under it really is...
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Grain bill weight, grain potential, strike volume, and end of mash SG can be used to calculate your conversion efficiency.
Grain bill weight, grain potential, pre-boil volume, and pre-boil SG can be used to calculate your mash efficiency.
Grain bill weight, grain potential, post-boil volume, and post-boil SG can also be used to calculate your mash efficiency.
Calculating pre- and post-boil mash efficiency is a good way to check the accuracy of your measurements. If the two don't match, it means that you have excessive measurement errors.
Volume changes ~4% between room temp and boiling. Not knowing the temp at which you measured volume can mean you start out with up to 4% error in your calculations, even before you take other measurement inaccuracies into account.
Once you know your conversion efficiency and your mash efficiency, you can calculate your lauter efficiency (lauter eff = mash eff / conversion eff.) If you have low mash efficiency, you need to know if it's because of low conversion or poor lauter technique, as the fixes are different for the two cases.
If you don't care how your process is performing, then you don't have to worry about collecting data. But, HBT is full of threads about "why is my efficiency low?", "why is my OG low?", etc. These questions cannot be accurately answered without the necessary data.
Brew on
Good advice above on process, but with your initial issue, your 1.020 is best explained by measurement error, likely from not well mixed sparge water. This is supported also by your observed vigorous fermentation, which a 1.020 OG wort would assuredly not be.
Didn’t catch method of measurement (refrac or hydro), but sample temperature can also play a role, so should bring to room temp, but this would not explain a ~30 point miss.
Didn’t catch method of measurement (refrac or hydro), but sample temperature can also play a role, so should bring to room temp, but this would not explain a ~30 point miss.
SRJHops
Why did the rabbit like NEIPA's so much?
Fair enough. Most of those numbers are calculated by the software I use, so I really just focus on measuring volumes, gravities, and ph. But if my numbers were way off, I agree conversion and efficiency are where I'd look.Grain bill weight, grain potential, strike volume, and end of mash SG can be used to calculate your conversion efficiency.
Grain bill weight, grain potential, pre-boil volume, and pre-boil SG can be used to calculate your mash efficiency.
Grain bill weight, grain potential, post-boil volume, and post-boil SG can also be used to calculate your mash efficiency.
Calculating pre- and post-boil mash efficiency is a good way to check the accuracy of your measurements. If the two don't match, it means that you have excessive measurement errors.
Volume changes ~4% between room temp and boiling. Not knowing the temp at which you measured volume can mean you start out with up to 4% error in your calculations, even before you take other measurement inaccuracies into account.
Once you know your conversion efficiency and your mash efficiency, you can calculate your lauter efficiency (lauter eff = mash eff / conversion eff.) If you have low mash efficiency, you need to know if it's because of low conversion or poor lauter technique, as the fixes are different for the two cases.
If you don't care how your process is performing, then you don't have to worry about collecting data. But, HBT is full of threads about "why is my efficiency low?", "why is my OG low?", etc. These questions cannot be accurately answered without the necessary data.
Brew on
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Strictly speaking, probably better to batch sparge over fly sparging first while learning the hobby. It will help to isolate problems elsewhere. But some hobbyists are in it because they enjoy complex problem solving or they like a challenge. I think if people understand the purpose of sparging is to extract the extra sugars available they get the beginning concept and can move on to mastering that part of the process. I think most will master batch sparging rather quickly such that if they want to fly sparge they will have a good base for reference. Like suddenly seeing a drop in efficiency when adopting or increased variability in efficiency.Yes, a correctly done fly sparge has higher lauter efficiency (and thus higher mash efficiency) than a batch sparge. However, it is much simpler for a beginner to get good and consistent results with a batch sparge, since channeling is not a possibility. All that is required is aggressive mixing prior to each run-off. With where the OP is in their learning, batch sparging is probably a good option until they can get consistent mash efficiency.
No sparge is even simpler than batch sparge, but takes a 8% - 9% hit on lauter efficiency (and mash efficiency) compared to single batch sparge (all else being equal.)
For a beginner, maximizing efficiency should not be the goal. Learning the process should be.
Brew on
Anyway you can't see the water's path through the grain. Clues that you may have channeling are depressions and water flow in specific spots at the top of the grain bed. Another is a seemingly abrupt lightening of the wort color exiting the MT. The color should gradually lighten but if abrupt then you aren't picking up sugars.
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one man's off-flavor is another's holy grain i guess...
i love it when i 'accidentally' get a beer that tastes like whole wheat bread, wish i could do it on purpose! (i'm waiting for @Fogey890 , who says he's really new to brewing answer my question. the grain is milled? because 1.020 would be about what i'd expect with whole kernels...and 2 lbs of honey in 5 gallon would be 1.014, so it is 'malt' right? i once tried brewing a 100% batch with rye berries, when i was realy new to brewing, didn't know they had to be malted!)
one man's off-flavor is another's holy grain i guess...
(i'm waiting for @Fogey890 , who says he's really new to brewing answer my question. the grain is milled? because 1.020 would be about what i'd expect with whole kernels...and 2 lbs of honey in 5 gallon would be 1.014, so it is 'malt' right? i once tried brewing a 100% batch with rye berries, when i was realy new to brewing, didn't know they had to be malted!)
OP said it was crushed.
Brew on
OP said it was crushed.
Brew on
damn, long thread. didn't see that....
(sorry)edit: and i forgot it was honey 'malt'...another apology would be in order.....
How are you measuring your gravity. Refractometer or hydrometer. A hydrometer at a high temperature would give a shockingly low OG.
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The grainy flavor cold crashed out and it turned out really good actually if you read the rest of the thread.... I rushed the bottling timeone man's off-flavor is another's holy grain i guess...
Cheers
Read through the whole thread and curious how the OP did on that subsequent batch. Some notes on the previous conversation. Morebeer has a notoriously coase crush. It looks like a .045 gap and leaves a portion of uncrushed kernels. Also agree low OG reading was also due to not mixing the stratified wort. If the filter in the mash tun is a narrow screen, better to batch sparge. If it is a perforated false bottom, fly can work. You need a little calcium in the mash and also a couple ml of lactic acid for beers that light.
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Gilbert Spinning Horse
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Having read through the thread I recon you're measuring your SG wrong. Your SG is measured from what's in the fermenter, not before.
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