Ounces of Corn Sugar Primer in a 3/4 Cup.

BrewSwag 728
Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
DudlyBrewRight

DudlyBrewRight

Active Member
Joined
Jul 5, 2023
Messages
37
Reaction score
18
Location
60457
I'm trying to figure out how many ounces of corn sugar to use for bottling 5 gallons of beer. I've read that 3/4 of a cup is the standard, but I also read that measuring with a scale is a better option. But there doesn't seem to be any agreement in how many ounces are in a 3/4 cup.
From Brew Cabin. "3/4 cup = 6oz."
From Howmany.wiki. "1.25 cups = 3.5 oz."
From Homebrew Talk. "3/4 of a cup is 4oz."
From American Homebrewers Association. "Papazian and Palmer and some folks on this blog have said that 3/4 cup (5.3 oz.) of corn sugar (or 5/8 cup of table sugar) is the correct amount to prime 5 gal. of beer for bottle carbonation."
So I've got 3/4 cup of corn sugar weights 6oz, 3.5oz, 4oz or 5.3oz.
There is no consistency. Does anyone actually know how many ounces of corn sugar I should use as primer for 5 gallons of beer? Or how many ounces of corn sugar are in a 3/4 cup? From what I'm seeing it appears that different brands of corn sugar must have different weights. Is that the problem. I'm very confused.
 
I use right at 5.2 oz for normal carbonation. You might have seen different amounts due to different styles. Wheat beers take more, some take less..it all depends on what style you're bottling.
 
First of all, how much priming sugar you should use depends on how much carbonation you want, which in turn depends on the style of beer and your personal taste. Second, Papazian and Palmer are right.
 
Since most people don't actually own or use corn sugar anymore, many of us would only be guessing.

What I do know is that I use 5/8 cup cane sugar (not corn sugar) per 5 gallons, and that this weighs 4.1 oz. I would not recommend using any more than 5 oz of either type of sugar, unless you love overcarbonation, gushers, and potential bombs. Me? I prefer to aim for just slightly less than average, just in case the yeast becomes overly excited in the bottle for any reason.
 
I think many still use corn sugar. I always use it rather than cane or beet sugar. I don't know if it really makes much difference, but I think I get finer bubbles with it. Also, beer kits always come with corn sugar.

Scales are cheap; use weight rather than volume, and make sure you use the correct beer volume in the calculator.
 
dmtaylor said:
What I do know is that I use 5/8 cup cane sugar (not corn sugar) per 5 gallons, and that this weighs 4.1 oz.
Click to expand...
Which will give you 2.4 volumes of CO2, at least according to Brewer's Friend.
dmtaylor said:
Me? I prefer to aim for just slightly less than average, just in case the yeast becomes overly excited in the bottle for any reason.
Click to expand...
And I prefer to aim for slightly more, just because I prefer a bit more fizz and mostly brew styles that should have a bit more fizz. But the difference between 2.4 and 2.6 volumes of CO2 shouldn't create any safety issues.
 
You can find plenty of kitchen scales on Amazon for under $10. They're cheap because they're cheap, but they're more than adequate for this purpose.
 
I have found the Brewer's Friend Calculator to be very good.
It will give you a fairly accurate result as to how much corn sugar to use for the volume of your beer and the temperature at which you fermented it. It also gives you a table of suggested carbonation levels based upon the style of beer you have brewed.

However, the result given for corn sugar (dextrose) is for anhydrous dextrose.
When corn sugar is exposed to air it takes on moisture, converting it into dextrose monohydrate which makes it heavier as it takes on about .9% water.

To get a reliable result, I always divide the given result by 0.91.
Eg. If the suggested quantity is 4.5 ounces corn sugar then: 4.5/ 0.91=4.95 ounces of your corn sugar is required.
 
How picky are you about how exactly your beer is carbonated to the vols of CO2 for your style of beer you brewed? If not picky then 3/4 cup of most any sugar is good enough. With some experience you might decide one style needs a rounded measure and the other a leveled measure.

If you are more picky about the amount of vols, then get a scale. Actually I find that weighing everything makes for less clean up as I can just pour things directly from the container into things I'm using directly and not have to dirty measuring spoons, cups or other volume measures.
 
I appreciate all the suggestions but I'm still a little confused so a little info about my brewing skills. I've dabbled with numerous canned malt varieties for at least 40 years, never did a full grain brew. In that amount of time I probably only brewed about 20 batches and only when the mood struck me. The best I've ever made is a variation of Charlie Papazian's Rocky Raccoons Crystal Honey Lager. Lager. Every one of his recipes calls for 3/4 cup of corn sugar for priming. Using that method has resulted in too little or too much carbonation so this time I'm looking to try weighing it with our mail scale which is pretty accurate. Using the suggested priming sugar calculator says I should use 4.1 oz of corn sugar for the "style" of beer I'm making but that amount is more than 3/4 of a cup. I remember bottles exploding once when I wanted more carbonation and tried 7/8ths of a cup.
Maybe someone can help me decide what style I'm actually brewing and how much primer I need.
As for carbonation, lets say something similar to Stella.
Here's my favorite successful recipe.
1 can of Coopers hopped English bitters extract.
1lb light dried malt.
2lb light honey
3.5 gallons of water in a 6 gallon carboy.
1tsp gypson.
1.5 gallons of water in brew pot with ingredients, boil 15min, add to carboy, pitch yeast when brew is about 75 degrees. (I cool it as rapidly as I can in a wash tub running cold water on the carboy, I don't have a wort cooler.)
I put a rubber stopper with a plastic tube in the top of the carboy and the other end of the tube in a gallon bottle 3/4 full of water so it's a closed system and blows out most of the crud.
When the bubbling stops I bottle it getting about 50 bottles.
With that information can anyone make an estimated guess on how much corn sugar I should use? And what "style" of beer this would be considered?
Thanks for all the previous suggestions.
 
DudlyBrewRight said:
Every one of his recipes calls for 3/4 cup of corn sugar for priming. Using that method has resulted in too little or too much carbonation
Click to expand...
If you get too much sometimes and too little other times, then there is something about your process that is inconsistent, no matter how much you might think you're doing it the same way every time. My guess is that your 3/4 of a cup is actually sometimes a little more and sometimes a little less.
DudlyBrewRight said:
Using the suggested priming sugar calculator says I should use 4.1 oz of corn sugar for the "style" of beer I'm making but that amount is more than 3/4 of a cup.
Click to expand...
According to what? Your postal scale? Probably not nearly accurate enough. Dry measures are also notoriously inaccurate. I just measured 3/4 cup of corn sugar and weighed it on digital my kitchen scale - three times: 5.3 oz, 5.6 oz, and 5.1 oz. The variation is not in my scale but rather in my ability to eyeball 3/4 of a cup. That's why I don't use dry measures when brewing.
DudlyBrewRight said:
When the bubbling stops I bottle it getting about 50 bottles.
Click to expand...
You're almost certainly bottling too soon, at least some of the time. That may also account for some batches being overcarbed and others being undercarbed.
 
mac_1103 said:
If you get too much sometimes and too little other times, then there is something about your process that is inconsistent, no matter how much you might think you're doing it the same way every time. My guess is that your 3/4 of a cup is actually sometimes a little more and sometimes a little less.

According to what? Your postal scale? Probably not nearly accurate enough. Dry measures are also notoriously inaccurate. I just measured 3/4 cup of corn sugar and weighed it on digital my kitchen scale - three times: 5.3 oz, 5.6 oz, and 5.1 oz. The variation is not in my scale but rather in my ability to eyeball 3/4 of a cup. That's why I don't use dry measures when brewing.

You're almost certainly bottling too soon, at least some of the time. That may also account for some batches being overcarbed and others being undercarbed.
Click to expand...
 
How long should I wait to bottle after there is no visible signs of fermentation?
One of the beer sights said 3.5 oz of corn sugar equals 3/4 cup so I weighed out 3.5 oz on our digital mail scale and it was exactly 3/4 of a cup. But when I saw other sights suggesting 4 to 5 oz I came here for clarification. You mentioned that, a measuring cup may not be accurate each time, but you also said a scale isn't either, so that's why you don't use dry measures. So do you use a portion of the wort? I think I read somewhere that that's an option but I have no idea how to do that.
 
DudlyBrewRight said:
One of the beer sights said 3.5 oz of corn sugar equals 3/4 cup so I weighed out 3.5 oz on our digital mail scale and it was exactly 3/4 of a cup. But when I saw other sights suggesting 4 to 5 oz I came here for clarification. You mentioned that, a measuring cup may not be accurate each time,
Click to expand...
And some of the advice was for tenths of grams. I think there is more likely to be a problem in how much beer there actually is. We (and I mean partial boil extract brewers like me and you) top to about 5 gallons in the fermenter. Not all of that gets bottled. I too learned to brew with Charlie Papazan and do 1 1/2 gal. boils. My fermenters weren't even marked for gallons, so I just added the rest of the not too carefully measured 4 gallons of water, without knowing how much boil off there was. After trub loss, it came out about 5 gal.

My point is 3/4 cup corn sugar works fine. I still use it. Your may for taste or style make that a strong 3/4s, but try to keep the amount of actual beer it's to work on consistent.
 
Last edited:
I just weighed 3/4 cup of sugar on my digital mail scale 10 times and got 5.40 or 5.35 consistently but I run my wife's leveling tool across the top of the cup not "eyeballing" as mentioned. I can't believe that 5/100 of an ounce can make any difference in 5 gallons of beer.
 
D.B.Moody said:
And some of the advice was for tenths of grams. I think there is more likely to be a problem in how much beer there actually is. We (and I mean partial boil extract brewers like me and you) top to about 5 gallons in the fermenter. Not all of that gets bottled. I too learned to brew with Charlie Papazan and do 1 1/2 gal. boils. My fermenters weren't even marked for gallons, so I just added the rest for the not too carefully measured 4 gallons of water, without knowing how much boil off there was. After trub loss, it came out about 5 gal.

My point is 3/4 cup corn sugar works fine. I still use it. Your may for taste or style make that a strong 3/4s, but try to keep the amount of actual beer it's to work on consistent.
Click to expand...
You may be right, I checked my records and see that one time I had 5.5 gallons of beer. Unfortunately I didn't record the end results so that may have been the low carbonation batch. I guess I'll just try the 3/4 cup method again and pay more attention to every detail, keep better records and hope for the best.
 
DudlyBrewRight said:
...you also said a scale isn't either...
Click to expand...
I certainly didn't mean to imply that scales in general aren't accurate. When you said you were using a postal scale I assumed that you meant an old-stlye analog spring scale. That's what I meant when I said it probably wasn't accurate enough. Since you have a digital scale that measures to the tenth of an ounce you can ignore that comment.
DudlyBrewRight said:
One of the beer sights said 3.5 oz of corn sugar equals 3/4 cup so I weighed out 3.5 oz on our digital mail scale and it was exactly 3/4 of a cup.
Click to expand...
DudlyBrewRight said:
I just weighed 3/4 cup of sugar on my digital mail scale 10 times and got 5.40 or 5.35 consistently
Click to expand...
These can't both be true. If you consistently find that 3/4 cup weighs 5.35 oz, then like I said yesterday, Charlie is right and the other web site is wrong. So stop listening to them and RDWHAHB.
DudlyBrewRight said:
I run my wife's leveling tool across the top of the cup not "eyeballing" as mentioned. I can't believe that 5/100 of an ounce can make any difference in 5 gallons of beer.
Click to expand...
If this is the way you've always done it, then you're right that that's not the explanation of your inconsistent carbonation.
DudlyBrewRight said:
How long should I wait to bottle after there is no visible signs of fermentation?
Click to expand...
Visible signs are not reliable. You said you had bottle bombs once; an extra tenth of an ounce of priming sugar won't do that, but bottling too soon will. You should check the specific gravity and bottle when it reaches something close to the predicted final gravity and stops changing. Many people advocate waiting another week or so after that so the yeast can clean up after themselves as it were.
DudlyBrewRight said:
And what "style" of beer am I brewing with the recipe I mentioned?
Click to expand...
Sorry, but I have no idea. Most British styles tend to be carbonated on the low side, but you're changing the recipe so who knows?
 
Last edited:
mac_1103 said:
I'm sure it is, but more importantly I had a typo in that post.
Click to expand...
A lot of people just use cane too. I don't think it matters a whole lot to be honest.

I bought a crap load of corn sugar years ago when Austin Homebrew was still Austin Homebrew and have enough until the cows come home.
 
DudlyBrewRight said:
How long should I wait to bottle after there is no visible signs of fermentation?
Click to expand...
I wait till the beer has cleared up. When I was using clear sided FV's, that was when I could see from one side to the far side of the trub layer.

By then all the sugars the yeast can possibly convert have been used.

Fermentation isn't the only purpose of the FV for a home brewer. It also serves to allow the yeast to deal with off flavors and aromas they create during their fermentation cycle. So don't rush your beer to bottle.

So far I've had no explosive bottles doing this and I sometimes carb to 3.5 almost 4 vols. Which would be a lot more sugar.
 
mac_1103 said:
"These can't both be true. If you consistently find that 3/4 cup weighs 5.35 oz, then like I said yesterday, Charlie is right and the other web site is wrong. So stop listening to them and RDWHAHB.

If this is the way you've always done it, then you're right that that's not the explanation of your inconsistent carbonation.
Click to expand...
When I weighed out 3.5 oz and it filled a 3/4 cup perfectly I was using corn sugar. When I verified the accuracy of my digital scale I used table sugar because corn sugar is too messy. Now I'm going to have to do it again because it doesn't seem like a 3/4 cup of table sugar is almost an ounce heavier than a 3/4 cup of corn sugar. Or maybe I should just listen to Charlie Papazian's advice and "not worry about it."
 
hout17 said:
A lot of people just use cane too. I don't think it matters a whole lot to be honest.

I bought a crap load of corn sugar years ago when Austin Homebrew was still Austin Homebrew and have enough until the cows come home.
Click to expand...

I did the same kind of thing and stocked up. Still have about 4 or 5 lbs.

After I use that up, no reason for me not to switch to cane--much cheaper. There used to be an urban legend about table sugar adding off-flavors, but think that's long since been debunked.
 
Surfing the web i stumbled onto Northern brewer fast prime. It comes in what looks like a can of beer and says it's the equivalent of 5oz of priming sugar for 5 gallons of beer and yields 2.5 volumes of CO2. Anyone ever tried it?
 
DudlyBrewRight said:
Surfing the web i stumbled onto Northern brewer fast prime. It comes in what looks like a can of beer and says it's the equivalent of 5oz of priming sugar for 5 gallons of beer and yields 2.5 volumes of CO2. Anyone ever tried it?
Click to expand...

Never tried it.

Looks like a $5.49 solution (see what I did there?) for a <$1 problem. But it sounds great for someone willing to pay an extra four and a half bucks to save the 30 seconds needed to measure some sugar. :confused:
 
MaxStout said:
Never tried it.

Looks like a $5.49 solution (see what I did there?) for a <$1 problem. But it sounds great for someone willing to pay an extra four and a half bucks to save the 30 seconds needed to measure some sugar. :confused:
Click to expand...
You forgot shipping. 😆
 
Kickass said:
https://www.northernbrewer.com/pages/priming-sugar-calculator
Use this calculator and a scale to prime.

Who cares what 3/4 of a cup is if you have a scale. Measuring dry goods by volume is inaccurate at best. That’s why you’re getting different answers.
Click to expand...
This is good advice, but I'm a casual extract brewer. I don't have a scale. I don't know the temperature of my beer. I don't know the exact temperature of the basement room the beer will sit in. And I don't know the exact amount of beer I have in the fermenter or that will end up in my bottling bucket. It will be about 5 gallons. 3/4 cup corn sugar, maybe a bit rounded for some styles, is close enough. This has worked for me for 299 ales since 1994. Others may opt to be less casual .:mug:

Edited to specify corn sugar for @DudlyBrewRight
 
Last edited:
D.B.Moody said:
This is good advice, but I'm a casual extract brewer. I don't have a scale. I don't know the temperature of my beer. I don't know the exact temperature of the basement room the beer will sit in. And I don't know the exact amount of beer I have in the fermenter or that will end up in my bottling bucket. It will be about 5 gallons. 3/4 cup, maybe a bit rounded for some styles, is close enough. This has worked for me for 299 ales since 1994. Others may opt to be less casual .:mug:
Click to expand...
3/4 cup of what? Corn sugar or table?
 
The difference between 3/4 cup of corn sugar compared to 3/4 cup of table sugar isn't going to make more than about 0.08 vols of carbonation difference for a 5 gallon batch. I don't think I'll be able to detect that when I pour or drink a beer.
 

Similar threads

R
Pliny the Elder to an APA
Replies
14
Views
1K
redrocker652002
R
madscientist451
Selzer/Beer Hybrid results
Replies
0
Views
478
madscientist451
madscientist451
Simon McIlroy
Corn Sugar Storage + Yeast Resurrection?
Replies
9
Views
802
IslandLizard
IslandLizard
MaxStout
Root Beer Extract Throwdown: Cook's vs. Zatarain's
Replies
4
Views
2K
OakIslandBrewery
OakIslandBrewery
_Keven
First time brewing how do I prime with belgian candi sugar?
Replies
4
Views
717
Jeroen79
J
BrewSwag 300

Latest posts

Back
Top