How to Make Limoncello and Determine ABV
Here is a quick way to make Limoncello and calculate the alcohol by volume (ABV). What you would need to do, is know your proof before you add sugar then do a calculation based on the volume of the added sugar or sugar-water mixture added.
So the steps you would take if you were back at square one is:
1. Use the Brewing America Alcoholmeter to test your alcohol to learn its proof level.
2. Infuse with your lemons.
3. Double check your proof after infusion to ensure there was no change.
4. Measure the volume of your proof liquid.
5. Mix your sugar-water solution and note your measurements (for repeatability for future mixes).
6. Measure the volume of your sugar-water solution you will add to your alcohol.
7. Note how much you cut your alcohol with your sugar-water solution.
8. Calculate your new alcohol proof based on the volume of your sugar-water solution to alcohol volume. (*see my note below)
9. You could use the Brewing America Triple Scale Hydrometer to test the BRIX level of your final mix (if you need the Brix Calculation).
*So if you have a mixture of liquid that is 1/3 to 1/4 the total volume of the liquid, and the other 3/4 to 2/3 other liquid has no alcohol content, then the proof would be reduced by that amount. So if your alcohol is 190 proof and is 1/3 of the final mixture then it is 190 multiplied by .6666666, which would equal about 126 proof. But if your alcohol is only 1/4 of the mixture then it is 190 divided by 4, which would equal about 48 proof. And then to find your ABV, ABV is simply half of your proof.
And finally, to summarize and look at some other considerations...
Once you've added simple sugar syrup the density of the liquid becomes much denser. Unless there is another fermentation period or distillation process, the proof will not increase, only decrease due to the amount of simple sugar syrup you added. Overall, in this mixture, if you want to decrease the alcohol taste, it is best to add more simple sugar syrup for dilution and to reduce the alcohol taste, making it more mild tasting.
But if you are looking at perfecting your recipe over time then I would say take a closer look at other variables at play here that affect the taste more than the actual change in alcohol level. Perhaps the lemon variety of sweetness/tartness and length of infusion time. Also the brand or base of vodka or alcohol you used. Then the final variable is the sugar syrup solution, if that changed from the last batch to this one, even down the boil time on the solution and evaporation of water during that process.
Like a science experiment, you should use repeat the experiment and change the variables noting the differences and outcome.
As I see it, the possible variables are:
1. Lemon variety and ripeness
2. Vodka or Moonshine variety and proof level
3. Length of infusion time and temperature
4. Simple sugar syrup mixture strength and amount
Using the same variety and ripeness of lemons and brand and proof of vodka, checking the vodka proof with the alcoholmeter you already purchased from us both before and after the infusion process, in case there was dissipation or some other variable at play. Then add your simple sugar syrup (noting mixture amounts) and check your sugar level after mixing in using our triple scale hydrometer and noting your BRIX reading.
But remember to have fun with this! You just need to do more research and development on your recipe and it's a great excuse to whip up your next batch! Sounds like you are well on your way to becoming a rockstar mixologist!
Happy Mixing! We are happy to help you answer any questions....just let us know!