Scientific Limoncello

[elriba]

Hi,
I think this might be of interest here.

There is an Italian guy, Dario Bressanini, who is a sort of food scientist. He has published a couple of books on the subject of the science of foods, and he has a VERY interesting video on YouTube where he describes his take on the scientific principles of making Lemoncello: THE SCIENTIFIC LIMONCELLO (just in time for Christmas)

The video is in Italian, but it has English subtitles. At least in Italy he seems to be a rather famous person, and the video too seems to be rather popular. I'll give here some of his insights, which I think are quite interesting.

(1) The recipe calls for 40g of lemon peels for each 100g of 95% alcohol (note he prefers to use weights in his recipes),
(2) Optimum extraction only requires from 1 to maximum 3 days. After only 1 day you get the most delicate flavor, and if you wait 3 days, you get a more typical limoncello flavor. After 3 days you start to get off-flavors. He cites some scientific papers to back his conclusions, and his own personal experience. I thought this was most interesting!
(3) If the extraction is carried out by placing the alcohol/peels in a 50C (122F) water bath, extraction time can be reduced to just a couple of hours. In his example, he placed the container in the warm water, and turned the heat off, waiting until the water reached room temperature (see at approx. at 15:57 in the video)
(4) The extracted essential oils are sensitive to light, and they are sensitive to acids; therefore, adding lemon juice to the final product will diminish the shelf life of the final product.
(5) The turbidity that you see in Lemoncellos is caused by the extracted essential oils being emulsified and it's characteristic of lemoncellos.

Where I live (in Panama), it's rather difficult/impossible to find 95% alcohol sadly. So, I've used vodka instead of 95% alcohol to make the lemoncello. It works ok, but when using 40% alcohol to extract the essential oils, you don't get the turbidity characteristic of lemoncellos. I'm not sure if it is because there is quantitively less extraction of the essential oils, or if it's because the essential oil emulsions somehow are not as visible; although it seems to me that the most probable reason is that there's just less oils being extracted. The other alternative is that I'm doing something wrong .

Hope this is of interest to you guys!

[MooseMan]

Very interesting elriba thanks for posting it.

Especially regarding the off flavours being extracted after 3 days.

[SouthwestAl]

Thanks for posting this - very interesting indeed!

400g of peel per kg of neutral (or 1.2L) seems a lot, and 3 days seems little - it's got to be worth trying!

My last batch of Limoncello was 100kg of lemons, (which gave me about 8kg of peel from memory), hand peeled and I swore I never wanted to see a lemon again, but I think I can put up with the hand cramps!

[elriba]

[Bushman]

It’s been a while since making Lemoncello thanks for sharing. I’ll have to go back and compare it to the recipe I use.

[SouthwestAl]

I gave this a go - first impressions are good, but he suggests it should rest once bottled for at least a week.

I did 200g of 95% (190 proof) neutral with 80g of chopped lemon zest, and left it in a dark place for 26 hours. His video mentions between 24 hours and 3 days, but he says try the 24 hour version first to see how you like it.

I added the 100g of sugar, and 230g of demineralised RO water, and stirred to allow the sugar to dissolve, filtered it through a basic strainer to pull out any undissolved sugar and bottled it. The colour is creamy and the yellow you would expect - he does mention that colour in = colour out more or less, so no great surprise there.

It's now resting in the bottle for a week to see how the flavour develops, but my initial impressions are that the flavour is brighter and lighter than my normal limoncello, which steeps for 5 - 7 days in a citrus 'vodka' @82% that i make with the left over lemons. My limoncello does not louche, but it does have way less than the 400g of peel per litre of neutral that this recipe calls for. By my calcs with some small, fresh Sicilian Lemons, weighing in at around 120 - 150g each, produces between 15g and 20g of peel. I used 5 lemons for 80g of peel, for around 0,5L of finished product (not measured it).

The left over peel certainly had some flavour still in it, and was not white and crispy as it would be after a longer steep, but based on what he says in the video, that means you are extracting out some of the less desirable flavour compounds anyway.

If life gives you Lemons, make Limoncello! Cheers!

[SouthwestAl]

as a coincidental aside, there was an article in the UK press this week about Limoncello suddenly appearing everywhere in London, riding on the tails of Aperol, as a popular mixer with Prosecco. Here are some of the drinks they mentioned to use with Limoncello:

Link to article: https://www.theguardian.com/food/2024/o ... SApp_Other

Five simple limoncello cocktails

All are delicious as they are, or you can garnish with a slice of lemon, lime or orange, or a sprig of mint or thyme.

Spritz
60ml limoncello
90ml prosecco
30ml soda water

Fill a large wine glass with ice. Add the limoncello, top with the prosecco and soda water, and stir gently.

Sorrento mule
45ml limoncello
45ml gin
15ml lemon juice, freshly squeezed
150ml ginger beer

Fill a tall glass with ice. Add the first three ingredients, stir, then top with ginger beer and stir gently again.

Negroni d’Amalfi
30ml Campari
30ml red vermouth
30ml limoncello

Put a large ice cube (or a few regular ice cubes) in a rocks glass or short tumbler. Add the ingredients and stir.

Lemon drop
60ml limoncello
30ml vodka
15ml lemon juice, freshly squeezed

Put the ingredients in a cocktail shaker with ice. Shake vigorously, then strain into a martini glass.

Sgroppino
15ml vodka
15ml limoncello
Scoop of lemon sorbet
Prosecco, to top

Mix the vodka and limoncello in a mixing glass with ice, then strain into a coupe. Add the lemon sorbet and top up with prosecco.

[Dougmatt]

Thanks for posting this. Reminds me I need to make limoncello…. I may try this and do 3 smaller batches cutting at 24 / 48 / 72 hours to see which I like best.

[NZChris]

My quick version uses close to the same amount of zest, higher temperature and different times.

I mostly use grape based spirit at around 78% abv, often from a sugar wash made using pomace, but sometimes refluxed brandy feints. I believe that grapes have beneficial flavors to add and suspect that some traditional makers use grape based spirit rather than neutral.

Nuke to 70C.
Leave to cool overnight.
Strain, then make up to desired sugar g/100ml and ABV %.

[GrumbleStill]

Interesting. Will definitely give this method a go for the next limoncello batch.