Oleo-Saccharum is Latin for ‘oil-sugar’. It is an old way of extracting every useable part from citrus.

Origins

Used origionally as an essential ingredient for Punch with its first recorded mention in 1670. In 1862, Jerry Thomas wrote in The Bartenders Guide “to make punch of any sort in perfection, the ambrosial essence of the lemon must be extracted”.

Now while we’re making it with Ruby Grapefruit, you can really apply this to any type of citrus.
The process depends upon the fact that sugar is hypertonic, which basically means that it is thirsty or in other words, the sugar eats liquid and there is a lot of juices locked in the peel.

Technique

As the rind is so much a part of this recipe, it’s important to use organic, unwaxed citrus. Now when you peel try as best you can to minimise the pith and a good Swiss-made peeler should help with that.

1. Make sure you wash your citrus before starting.
2. Peel the citrus, trying to get as little pith as possible
3. The basic rule of thumb is that you want to do about 2oz of Sugar per fruit, now Grapefruit is a little bigger than Lemons, Limes or Oranges but its also a little drier, so its a safe bet that the rule probably still holds true.
4. Place everything in a large jar and shake. Leave overnight (shaking whenever possible)
5. To lengthen the Oleo Saccharum and dissolve any remaining sugar, add the same volume of juice as you do sugar (back in step 4)
6. Reseal the jar and shake until sugar is dissolved.

Alternatively … If you have a vacuum sealer, then use the Jeffrey Morgenthaler technique

1. Muddle Citrus peels with Caster Sugar in a bowl
2. Pour muddled peels and sugar into a vacuum bag, remove air from the bag and seal.
3. Leave it to infuse for at least 6 hours at room temperature (preferably 12 hours if possible) for the sugar to leech out and absorb the citrus oils.
4. Date and refrigerate the sealed bag until required (within a week).

The peels will get a little bit stiff and brittle, they physically lose density and volume as they are releasing their oil
You can drink it with soda, which will make a wonderful Grapefruit Soda or add it to a drink like a Paloma.