Gravity too low

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mathiascote

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Hey all,

I'm pretty new to this. I am trying to make the Northern Brewer's West Coast Radical Red extract kit. You can see the recipe here for reference.

I thought everything went well, but I was disappointed at the end when I measured the gravity at only 1.026, vs the recipe's expected 1.054. That seems like a pretty big discrepancy to me.

I am trying to figure out where I went wrong, I have a few guesses but maybe someone here can help me say for sure.
  • On the grain steeping step, I found their instructions ambiguous, "steep for 20 minutes or until water reaches 170f". I think they meant to steep as the water was warming... I ended up steeping for 20 minutes at 140, as someone told me that was a good steeping temperature. Should I have done it at 170 for 20 minutes? Or increased to 170 at the end?
  • I tossed in a whirfloc tablet 15 minutes before the boil ended, because I figured it couldn't hurt anything... but maybe it did?
  • At the end of the boil, there wasn't really much in the way of sludge at the bottom, so I went ahead and put the whole kettle into the fermenter.
  • I did go a little over 5 gallons, maybe like 5 1/3, to hopefully end up with 5 gallons drinkable without the trub. I'm sure that lowered the gravity somewhat, but surely not that much.
One other question, should I consider adding some corn sugar while it's still fermenting, to try to compensate?
 
Welcome to HBT!

From NB recipe instructions:
8. Fill primary fermenter with 2 gallons of cold water, then pour in the cooled wort. Leave any thick sludge in the bottom of the kettle.​
9. Add more cold water as needed to bring the volume to 5 gallons.​
Did you top up with water and stir very well? If not, it may not have mixed all the way, when you took your reading.

Did you check the calibration of your hydrometer in distilled or RO water, making sure it actually works? Reading in plain water at around 60-68F should be about 1.000.

Most extract recipes will always be very close to their intended Original Gravity (OG), unless you lost fermentables, due to splashing, waste, thrown out with trub, etc.
 
Hmm, I added the water and did shake it some, but I didn't stir it at all. "Rock back and forth" was their term. Do you normally stir it up? Definitely possible it was not that well mixed.

I just checked hydrometer with some tap water and it was pretty close to 1.000. Not really too concerned about a .001 or .002 difference at the moment as long as it's in the ballpark.
 
Hmm, I added the water and did shake it some, but I didn't stir it at all. "Rock back and forth" was their term. Do you normally stir it up? Definitely possible it was not that well mixed.
Yeah, it's amazing how sugary solutions and water stratify, refusing to mix quickly and thoroughly.

Use your long plastic brewing spoon to stir and mix well, or the backend of it, if it's a narrow neck. Make sure to only use clean and sanitized tools when touching (chilled) wort and beer. ;)

Are you using a glass or plastic fermenter?
 
It's plastic. I will definitely do that next time, thanks.

So for this one, did I screw up anything other than my measurements? It seems to be fermenting away quite nicely at the moment, I am hesitant to touch it.
 
It's plastic. I will definitely do that next time, thanks.

So for this one, did I screw up anything other than my measurements? It seems to be fermenting away quite nicely at the moment, I am hesitant to touch it.
Ah, good, plastic is safe to handle. Large glass vessels not so...

No, it doesn't matter, nothing is screwed up. The yeast activity will churn the beer and mix it up.

You do want to keep your fermentation temps toward the low end of your yeast's range. That makes better beer and prevents fusel alcohols and other off-flavors from developing, at high(er) temps. So, a cooler place is usually advised, since fermentation created heat, which speeds things up, which created more heat...
Which yeast did you use?

Also protect your beer from light at least for long periods.
And stay away from secondaries, they're not needed (with very few exceptions). Just leave it in the "primary" until ready to package.
 
It seems to be fermenting away quite nicely at the moment, I am hesitant to touch it.

There is real wisdom in that statement.

This thread got me reading my notes from my first batch. I made a Sierra Nevada Pale Ale clone that was so bitter it tasted more like their Torpedo than any pale ale I've tried.

If it's fermenting, it's making beer. It may not be what the recipe intended, but it's your beer! Welcome to the hobby and cheers!
 
I used the dry yeast, Safale US-05. I have it sitting inside under the stairs, it's dark, although not quite as cool as I'd like. Probably around 70, but it's the best spot I got. Thought about putting it in the garage but was afraid it would get low enough to kill the yeast overnight. I stuck a few ice packs around the fermenter, maybe that will help 🤷‍♂️

And will do on skipping the secondary.
 
There is real wisdom in that statement.

This thread got me reading my notes from my first batch. I made a Sierra Nevada Pale Ale clone that was so bitter it tasted more like their Torpedo than any pale ale I've tried.

If it's fermenting, it's making beer. It may not be what the recipe intended, but it's your beer! Welcome to the hobby and cheers!

Thank you for the encouraging words.
 
Don't add any sugar as that will change the recipe and make the final product dryer.
I read through the recipe and it's easier to put the cooled wort in the fermenter first and then top all the way to five gallons. On the other hand, with the recipe directions, pouring into two gallons of cold water automatically stirs it. Maybe I'm just always stirring well but I've never had that separation which leaves the lighter ingredients on top to skew the OG reading.
1/3 of a gallon is a lot of water and played a part in the lower OG than expected.
A five gallon batch doesn't yield five gallons of bottled beer, more like 4.25 gallons and no way to avoid that unless you raise all of your ingredients by a percentage (not just the water which will make a weaker beer).
Back to the stratification, since your hydrometer is accurate enough, I don't know what else it could be besides not mixing well.
I'm sure it will turn out good. You can make lots of errors and still get decent beer.
 
I thought everything went well, but I was disappointed at the end when I measured the gravity at only 1.026, vs the recipe's expected 1.054. That seems like a pretty big discrepancy to me.
Since this was an extract kit and your final water volume was pretty close to the kit instructions, you can assume your OG was very close to the predicted number. It’s good that you checked, but OG numbers with extract kits really aren’t too important in my opinion. Checking the FG before packaging is important though. With regards to the steeping grains, I’d try to keep it closer to 150° for 20-30 minutes if you can. You’ll extract a small amount of sugar from them, but they are mostly for additional flavor and color contributions.
Good luck with your brew, it sounds like you’re off to a good start.
Sláinte
Nick
 
At the end of the boil, there wasn't really much in the way of sludge at the bottom,
Extract brews are quite "clean" in that regard. All the sediment of the grain mash have been removed by the maltster before condensing the wort into a syrup or dry powder. You may get some additional hot and cold break (looks like little fluffy clouds or soft flakes in your wort), and if you didn't contain (bag) or filter out your hops, they'll be in your fermenter too. They will all sink once active fermentation has completed, and actually may help clarifying the beer.

I have it sitting inside under the stairs, it's dark, although not quite as cool as I'd like. Probably around 70, but it's the best spot I got.
70F is a bit high for most ale yeasts including US-05. 64-66F is a better target. Look into ways to keep the fermenter cooler, especially during the height of fermentation. Toward the end, after the big event is over, 70-74F is good to let her condition for a week, and possibly eek out another point or 2, before packaging.

I use a (large) Igloo beverage cooler with the 1 or 2 fermenters inside, and filled about 1/2-3/4 way with cold water. I then add a few frozen water bottles to that water jacket once or twice a day to keep the actual fermentation temps at 64-66F.
There are many ways to lower the temps a few degrees, mostly variations on a water jacket or swamp cooler.

But for your first brew, RDWHAHB! (Charlie Papazian).
 
I use a (large) Igloo beverage cooler with the 1 or 2 fermenters inside, and filled about 1/2-3/4 way with cold water. I then add a few frozen water bottles to that water jacket once or twice a day to keep the actual fermentation temps at 64-66F.
There are many ways to lower the temps a few degrees, mostly variations on a water jacket or swamp cooler.

Thanks for the advice, I will definitely look into these for future. For now, since I have the house to myself, I have turned off the heater and put on a jacket 🤣
 
For now, since I have the house to myself, I have turned off the heater and put on a jacket 🤣
We do about anything for making good beer!

Setting the fermenter in a tray or basin with some water and an old t-shirt draped over the fermenter, wicking up the water, and a small fan aimed at it makes a swamp cooler. The space underneath stairs can be excellent as a fermentation area if you can easily control the temps.

In a townhouse we rented for a few years there was a "coat closet" having one outside wall. A perfect fermentation space for the cold half of the year. The back of the lower level was halfway underground, which was good for the warmer half of the year.

It's also so much easier to add a little localized heat rather than remove it. ;)
 
i learned a neat new trick last year. when it's done fermenting, if you have both a refractometer, and hydrometer. you can tell what the OG actually was after the fact.....
 
I tossed in a whirfloc tablet 15 minutes before the boil ended, because I figured it couldn't hurt anything... but maybe it did?
It didn’t hurt anything but 1/2 a whirlfloc tablet with five minutes remaining is a better procedure (for 5 gallons). Break it in half and keep the rest in a ziplock for a later brew.
 
The steeping grains wouldn't make that big a discrepancy. Yes, you could have steeped a bit higher. I would have put them in at 145 and raised the temp to about 156 gradually over 30 minutes and held it there for another 10 or 15 minutes, then turned the fire up and pulled the grains at 170. Steeping longer doesn't hurt anything except maybe allow more tannins into the beer. Bad thing or good thing? You tell me. Your beer. With malted steeping grains, you will extract a tiny bit more sugar if your "steep" is closer to an actual mash. Your steeping grains amount to less than two pounds total and the difference would not be at the earth shattering kaboom level.

I suspect your wort was stratified when you took the reading. I don't see what you could do to make an extract recipe come in at 28 points lower than expected. At any rate, let's say your FG ends up around 1.008. The gravity reduction will be .018 and .018*131.25=2.3625 ABV. Still beer, not near beer. If you subtract your FG from you OG and multiply by 131.25 you get a pretty close estimate of your ABV. Lower FG typically indicates a crisp and dry beer. Higher FG indicates possibly more body and maybe even residual sweetness. Raising the OG by adding corn sugar will help the ABV but may make the beer seem thinner and drier than you would like. I think I would leave well enough alone. If you had a little more DME you could maybe add a pound of that, but I believe I would just wait this one out and see what happens. You may get a very picquant and fragrant session beer out of this, especially if you like hoppy beers.
 
I found your problem. Your recipe is not for a 5 gallon batch. It is for a 3.5 gallon batch. Actually it would be closer to 4 I think. You start with 2.5 gallons. 60 minute boil. Lose a half gallon or more. Add 2 gallons. That's under 4 gallons in the fermenter and you have 5.5. If you crunch the numbers, you will account for at least most of your discrepancy.

<EDIT> you would have a OG of about 1.040 or 1.041 using the same measuring technique but with the final volume of 3.5 gallons as per the recipe. So that's part of it but not all of it. 4.2% ABV calculated.
 
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I found your problem. Your recipe is not for a 5 gallon batch. It is for a 3.5 gallon batch. Actually it would be closer to 4 I think. You start with 2.5 gallons. 60 minute boil. Lose a half gallon or more. Add 2 gallons. That's under 4 gallons in the fermenter and you have 5.5. If you crunch the numbers, you will account for at least most of your discrepancy.


i just punched 6lbs liquid extract, and a pound of dry into beersmith for 5 gallons, it gives me 1.052?

and with the 1.25 lbs of crystal rye...should be a bit higher...
 
I found your problem. Your recipe is not for a 5 gallon batch. It is for a 3.5 gallon batch. Actually it would be closer to 4 I think. You start with 2.5 gallons. 60 minute boil. Lose a half gallon or more. Add 2 gallons. That's under 4 gallons in the fermenter and you have 5.5. If you crunch the numbers, you will account for at least most of your discrepancy.

<EDIT> you would have a OG of about 1.040 or 1.041 using the same measuring technique but with the final volume of 3.5 gallons as per the recipe. So that's part of it but not all of it. 4.2% ABV calculated.

Step 9 is to add more cold water to bring the volume to 5 gallons
 
i just punched 6lbs liquid extract, and a pound of dry into beersmith for 5 gallons, it gives me 1.052?

and with the 1.25 lbs of crystal rye...should be a bit higher...
Step 9 is to add more cold water to bring the volume to 5 gallons
I agree with both of these. Rough calculations in my phone app put it at 1.052 like @bracconiere calculated. I’ll also agree the steeping grains could add a point or 2. Like I said above, if the instructions are followed to the T, predicted OGs are usually spot on.
 
i learned a neat new trick last year. when it's done fermenting, if you have both a refractometer, and hydrometer. you can tell what the OG actually was after the fact.....

Curious how this works, Google is not being very helpful. My wife has been thinking of getting a refractometer for work, it would be interesting to compare in a few weeks.
 
I am trying to figure out where I went wrong
At a high level there are two factors (sugars and water) that result in too low gravity:
  1. Too little sugar was extracted or added
  2. Too much water ended up in wort
Of course there are 4 possible combinations of too much / too little that ultimately result in the realized OG. Determining where things went wrong starts with determining the sugar points that ended up in your kettle and that should have ended up in your kettle.

Actual sugar points in kettle = 5.33 gallons * 26 (last two digits of SG) = 138 points

Expected sugar points per recipe:
6 pounds LME = 36 point per pound * 6 = 216
1 pound DME = 44 points per pound *1 = 44
.75 pounds of Crystal Malts steeped = 14 points per pound * .75 = 11 points
Total points of sugar = 271

Right of the bat it is clear that the main contributor to your significant gravity miss is not the steeping of the specialty grains as they could only account for a max 4% of the total amount of sugar in your kettle.

Also, LME and DME points always end up in the kettle unless you leave a lot of it in the packaging. That said, there is something very wrong with either what came in your kit, the water quantity measurement in the fermenter, or your gravity measurement as if you had 5.33 gallons of wort at 1.026 in your kettle then you are missing nearly half the sugar that is in the DME or LME. Sugar does not boil away.

At this point it does not make sense to go any further because something is very wrong:
  • Either your gravity reading is incorrect (how did you take it - refractometer (you may have had stratification), or
  • You volume measurement is significantly off, or
  • The kit did had too little LME or DME
Can you verify any of the above?

BTW, learning to count points and adjust your preboil gravity is an easy and important skill to being able to hit your gravity every time and determine what went wrong in an analytical way.
 
As was mentioned, barring any missing ingredients and the ability to measure water, you always will come extremely close to the recipe OG. All the mass will be in the fermenter when you top off.
 
  • Either your gravity reading is incorrect (how did you take it - refractometer (you may have had stratification), or

Based on other replies I am feeling pretty certain this is the problem. I used a hydrometer on a sample from the top at the end, after adding cold water on top of the wort, so it seems logical that I might have gotten water that did not have the sugars fully mixed into it yet.

All the ingredients they gave me are in there, so that seems like the most likely explanation.
 
i just punched 6lbs liquid extract, and a pound of dry into beersmith for 5 gallons, it gives me 1.052?

and with the 1.25 lbs of crystal rye...should be a bit higher...
Ah my bad. I didn't use a recipe calculator, just multiplied the found OG minus 1 by 5.5 and divided by 3.5 and added the 1 back. I had read down to step 8 and said, "Ah-HAH!!! J'e ACCUSE!"

Anyway It almost has to be the reading was false, and so it should turn out okay with no added sugar.
 
I searched the Northern Brewer site and did not find a batch with those parameters.
Yeah I was wrong. Instructions said boil 2.5 gallons and add to two gallons in the fermenter. BUT they also said, further down past how far I read, to then top off to the 5 gallon mark. I got my start with an NB extract kit, too. I didn't remember any that size, either, but my alligator-jawed mind clamped down on the 2.5 gallon boil and the 2 gallons cold water in the fermenter, and I saw 3.5 gallons somewhere and somehow tied that to 3.5 gallon bottling kit... need another cappuccino I guess.
 
Yeah I was wrong.
I was really hoping you were right. It would have made sense. Oh, well.
I like taking NB recipes and buying the ingredients, the logic being that they already tested the recipe. Their Dragon Silk (spin on Dragon's Milk) came out especially well.
 
Curious how this works, Google is not being very helpful. My wife has been thinking of getting a refractometer for work, it would be interesting to compare in a few weeks.


if you get a refrac that reads BRIX, ethanol raises the reading and lowers a hydrometer.....so comparing the two will give you a pretty good estimate of ABV, and what the OG was....a refrac reading of 6.5 BRIX would be like 1.026 for a FG, but assuming it has alchol, and a hydrometer is reading 1.008...you can use a calculator that's programed by someone smarter then me to get an idea about all this... ;) :mug:

edit: third one down on this....


https://www.northernbrewer.com/pages/refractometer-calculator
wish i knew about it 10 years ago when i was trying to figure out how much alcohol i was making in my sake attempts....being you add rice gradually....way better method then the vintometer i bought!
 
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@GrowleyMonster : I'm finding that NB extract kit instructions change slowly over the years. This one specifies a concentrated boil (1/2 the water and all the extract at the start of the boil) but doesn't mention secondary fermentation in the step-by-step instructions. Others are (or were) partial boil with late extract additions.
 
Back to fermentation temperature for a second. You said "70" but that was probably the ROOM temperature. While that influences fermentation you are really interested in your WORT temperature. Figure out a way to get a thermormeter to measure your wort temp. The stick on strips work well with plastic fermenters. FYI, fermentation is initially pretty exothermic. In a 70 room you could easily have a 80 degree wort temperature for a few days.
 
i learned a neat new trick last year. when it's done fermenting, if you have both a refractometer, and hydrometer. you can tell what the OG actually was after the fact.....
Curious how this works, Google is not being very helpful. My wife has been thinking of getting a refractometer for work, it would be interesting to compare in a few weeks.

calculator here: "Approximate ABV and Original Gravity from current Brix and Gravity converter" (link).

equations here: "Calculating ABV without OG" (link).

IIRC, the equations are from a magazine article (probably Zymurgy, maybe BYO) from mid-2010s.
 
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Back to fermentation temperature for a second. You said "70" but that was probably the ROOM temperature. While that influences fermentation you are really interested in your WORT temperature. Figure out a way to get a thermormeter to measure your wort temp. The stick on strips work well with plastic fermenters. FYI, fermentation is initially pretty exothermic. In a 70 room you could easily have a 80 degree wort temperature for a few days.

Hmm, okay so let me make sure I've got this right. The yeast says ideal range is 59-75, which made me think 70ish room would be fine. But in actuality, I want the wort itself more on the low end, like 60-65. And because of the heat it's generating, the ambient temperature would need to be more like 50-55? Which realistically means not relying on the ambient temperature, but doing an occasional ice bath or something and babysitting the temperature, at least for a few days.
 
But in actuality, I want the wort itself more on the low end, like 60-65. And because of the heat it's generating, the ambient temperature would need to be more like 50-55?

i find that starting the wort cooler than the recommended temp and allowing it to come to the low end of its range within a day works well. If I let my beer ferment in a room that is 62 ambient, I notice that my beer is likely at about 64-65, right in the middle of its range. Starting at 72, I might get my beer temp up to near 80 at the peak of fermentation because the yeast work so much faster at that warmer starting temp that they can drive the beer temp up higher.
 
This one specifies a concentrated boil (1/2 the water and all the extract at the start of the boil) [...] Others are (or were) partial boil with late extract additions.
Thanks for pointing that out.
Sadly, there's little rhyme or reason to their instructions. They've always been, and still are, confusing, misleading, or sheer wrong.
 
Hey all,

I'm pretty new to this. I am trying to make the Northern Brewer's West Coast Radical Red extract kit. You can see the recipe here for reference.

I thought everything went well, but I was disappointed at the end when I measured the gravity at only 1.026, vs the recipe's expected 1.054. That seems like a pretty big discrepancy to me.

I am trying to figure out where I went wrong, I have a few guesses but maybe someone here can help me say for sure.
  • On the grain steeping step, I found their instructions ambiguous, "steep for 20 minutes or until water reaches 170f". I think they meant to steep as the water was warming... I ended up steeping for 20 minutes at 140, as someone told me that was a good steeping temperature. Should I have done it at 170 for 20 minutes? Or increased to 170 at the end?
  • I tossed in a whirfloc tablet 15 minutes before the boil ended, because I figured it couldn't hurt anything... but maybe it did?
  • At the end of the boil, there wasn't really much in the way of sludge at the bottom, so I went ahead and put the whole kettle into the fermenter.
  • I did go a little over 5 gallons, maybe like 5 1/3, to hopefully end up with 5 gallons drinkable without the trub. I'm sure that lowered the gravity somewhat, but surely not that much.
One other question, should I consider adding some corn sugar while it's still fermenting, to try to compensate?
Once post-boil temp comes down to <80, I rack to a 6.5 gallon bucket and pour back & forth between that and another sanitized bucket 3 or 4 times to aerate. If you have multiple buckets you could get your volume right then pour back & forth, aerating and mixing any top off water thoroughly for an accurate reading.
On this one I'd assume an OG of 1.045-1.050 due to your volume issues and continue learning & improving every time.
 

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