How to calculate alcohol in liqueurs step by step

[Demy]

I would like to share with the whole forum my method for estimating the alcohol content of homemade liqueurs. I have often read here and elsewhere about the difficulty of how to move to calculate this figure and I would like to make my contribution. This is an estimate not a super-scientific method, for example it does not take into account the intermolecular forces of water/alcohol mixtures where 1+ 1 does not make 2, but it is still a more than acceptable estimate.
In general, the basic ingredients of a liqueur are water, alcohol, sugar.
I begin by saying that we generally measure alcohol by volume (ABV). Any ingredient that changes the volume of our liquor will affect the alcohol content.
It is quite intuitive that the more water is added (for the same alcohol) the less alcoholic our liqueur will be due to dilution. When we talk about sugar sometimes it creates confusion.... Does sugar have an influence on the alcohol content? Sugar increases the total volume of our liqueur so it lowers the alcohol content. This means that if to a liqueur made with 1 part of alcohol 1 part of water we add sugar in fact we increase the total volume then the alcohol content is lowered.The first operation I do then is calculate how much volume the sugar occupies.
Imagine a hypothetical recipe made with: 750ml water; 500ml alcohol at 95 abv ;150grams sugar
Sugar is in grams so we have to transform it ml to know how much volume it occupies.
Just divide the weight of sugar by its density, the density of sugar is about 1.59 therefore... 150(gr)/ 1.59 = 94 ml (approximately).
Now we can calculate the total volume of our liqueur by adding all the ml of the recipe 750ml(water) + 500ml(alcohol) + 94ml (sugar)= 1344ml
Now we calculate the alcoholic contribution by multiplying ml of alcohol by its abv then.. 500 x 95 = 47500
To derive the alcohol content we divide this number by the total volume found previously 47500/1344= 35 ABV (approximate)
This is what I do to design a recipe (for example limoncello) others maybe do differently but I hope it will help the forum.

[Demy]

I also made a very short video if you want to watch it.

[Kareltje]

I can not see the video, but indeed: your reasoning is sound and works well.
Some years ago I made a small Excel-file to do the same and the central formula is exactly as you describe.
Only I took 1,616 kg/l for sugar. But that can easily be changed.

Yellow cells to be given, green cells intermediate, red numbers to check.

[Hügelwilli]

I have done some density measurements of ethanol-sugar-water-solutions. And the measured densities were surprisingly low. Lower than with a rough calculation like this. It seems that sugar and ethanol repel each other that the volume of the mix expands.
I will do better measurements next year and probably program a calculation tool for this. Biggest problem will be that the temperature correction neither for ethanol-water-solutions nor for sugar-water-solutions is valid.

[monstersX]

Hi Hugelwili

looking at adding this to my app, what do you think?

[Hügelwilli]

It's up to you. As you can read, I have doubts.

[Demy]

I don't know what the doubts really are, some people here on the forum use much more approximate methods, so those who know a better method might expose it. I don't think I've ever read about anything better on a hobby level here on the forum.

[NZChris]

When making simple syrup, I measure the final volume so that I know it's g/l. Measuring the weight would be helpful too.

To make a known volume of liqueur;
Calculate the volume of spirit to use.
Add the sugar, or the calculated amount of simple syrup.
Make it up to the target volume, mixing well.
If accuracy is required, recheck and top up at 20C.

If you checked the weight at each step, you could then use scales to make up any sized batch.

[Metalking00]

Like NZchris' method, I always start off by using the dilution calculator to see how much water it takes to make the target abv, then use that amount of water and my desired amount of sugar to make a syrup. Then measure that syrup out to the volume specified by the dilution calculator to achieve my target abv. Any extra syrup (which isnt much) just goes to making cocktails.

[NZChris]

I always start off by using the dilution calculator to see how much water it takes to make the target abv,...

Many of the online dilution calculators are flawed, which is why I often use the finished volume rather than 'water to add'. If you ask a calculator to dilute a liter of 80% to 40% and it says to add 1 liter, it is faulty. The correct answer is closer to 1.040l.

[Demy]

I always start off by using the dilution calculator to see how much water it takes to make the target abv,...

Many of the online dilution calculators are flawed, which is why I often use the finished volume rather than 'water to add'. If you ask a calculator to dilute a liter of 80% to 40% and it says to add 1 liter, it is faulty. The correct answer is closer to 1.040l.

Exactly. As I wrote at the beginning of the post 1 liter of water + 1 liter of alcohol does not 2 liters.

[Demy]

I always start off by using the dilution calculator to see how much water it takes to make the target abv,...

Many of the online dilution calculators are flawed, which is why I often use the finished volume rather than 'water to add'. If you ask a calculator to dilute a liter of 80% to 40% and it says to add 1 liter, it is faulty. The correct answer is closer to 1.040l.

Exactly. As I wrote at the beginning of the post 1 liter of water + 1 liter of alcohol does not 2 liters.

[Metalking00]

Many of the online dilution calculators are flawed, which is why I often use the finished volume rather than 'water to add'. If you ask a calculator to dilute a liter of 80% to 40% and it says to add 1 liter, it is faulty. The correct answer is closer to 1.040l.

I knew that 1+1 doesnt equal 2 when it comes to alc and water, but i thought the calculator on the parent site took that into account. Now, looking closer, i see that youre right, it doesnt.

Ill look for a more accurate calculator. Do you have any recommendations? A few mintues of looking also turned up the TTB tables showing the alc/water component amounts for each proof and the formula to calculate the amount of water needed to dilute a given amount of alc to a specific abv, though it appears to be for a quantity of 100 gallons. Neat stuff, learned something new!

[monstersX]

My app takes contraction into account fyi

https://play.google.com/store/apps/deta ... distillers
https://apps.apple.com/ca/app/distiller ... 1600736639

Many of the online dilution calculators are flawed, which is why I often use the finished volume rather than 'water to add'. If you ask a calculator to dilute a liter of 80% to 40% and it says to add 1 liter, it is faulty. The correct answer is closer to 1.040l.

I knew that 1+1 doesnt equal 2 when it comes to alc and water, but i thought the calculator on the parent site took that into account. Now, looking closer, i see that youre right, it doesnt.

Ill look for a more accurate calculator. A few mintues of looking also turned up the TTB tables showing the alc/water component amounts for each proof and the formula to calculate the amount of water needed to dilute a given amount of alc to a specific abv, though it appears to be for a quantity of 100 gallons. Neat stuff, learned something new!

[Metalking00]

My app takes contraction into account fyi

https://play.google.com/store/apps/deta ... distillers
https://apps.apple.com/ca/app/distiller ... 1600736639

Perfect! Thank you!

[EricTheRed]

Hi
The sugarwash calc doesn't accept decimal amountta

[Garouda]

Assume I have 1.5 litres @ 95% ABV and I want a liquor @ 43% ABV, taking the contraction into account I need to add 1.9 L. of water.
I want to use a syrup @ 50% Brix, assume that the contraction is the same as with water.
To make 1 litre of syrup @ 50% Brix, I need 614g of sugar, volume = 386 ml, and so 614 ml of water.
Scaling up to 1.9 litres. I need 1,173 kg of sugar = 737 ml and 1173 ml of water, 1173 + 737 = 1.9 litres I need to reach 43% ABV.
It's not rocket science, so there's no need to be precise at three decimals...
I made more or less the same assumption as in the initial post, taking a density of 1.59...

[BrewinBrian44]

I used part of this OP method recently to make a batch of peppermint liqueur. My first time making a liqueur.

I calculated how much sugar based on recommendations of “grams per liter” from some other threads on HD. I came to the number of 150g/liter for my preferences.

Since I wanted to fill a 750ml bottle, I had to cross multiply and divide 150g/1liter with X/.750liter. This came out to 112.5g of sugar. I then determined how many milliliters this would take up in the total volume by dividing by the density “1.59.” This came out to 70.75ml.

I used an online calculator to determine how much water and alcohol I’d need to fill a 750ml bottle. I simply subtracted 70.75ml from the water amount.

After gathering these numbers, I mixed everything up and boom, exactly 750ml with the sweetness I like at 50% ABV.

Some of you are probably thinking “wow, 50% is quite high for a liqueur.” This spirit is for my degenerate friends who love taking shots of Rumpleminze, the goal being obvious haha!

I plan to post about the recipe in another thread.

[Demy]

Excellent