How to make rum Cornish distillery

Distilling Rum. How to make Rum

Once the fermentation is complete, the rum wash is needed to be distilled.

There are many options for this process from continuous distillation, column or pot still distillation to name a few. 

We chose pot still to keep as much flavour in our rums as possible. Column stills are great for creating vodkas or spirits that require cleaning up or a more neutral taste, but with heavy rums and whisky it is all about the flavour such as Honey Rum.

The still is heated up so the rum wash inside boils. Alcohol boils at a lower temperature than water so that would be the first to turn to gas and head into the neck of the still. This is then cooled, and the alcohol turned back to liquids, all to be collected in vessels below.

We do a double distillation where the first part is called a stripping run. This removes all the alcohol from the rum wash and is run as fast as possible.

The spirit produced is called low wines. This is 30% ABV and definitely not suitable for drinking as it still contains all the nasties, such as methanol.

The liquid left in the still has no alcohol in it. It is called dunder, and is pumped outside to our dunder tanks where the bacterias and wild yeasts can feed on the last remains of sugars and we can then reuse this for our next rum wash.

Once all the original rum wash has been run and converted into low wines, we can start the second distillation.

Spirit Run

This is run slowly and carefully and takes about nine hours to complete.

The temperature and ABV  is measured constantly and just as before, the alcohol rises and is cooled down.

The first spirit to come across are the foreshots. Foreshots are the first vapours to boil off during distillation, usually containing compounds such as acetone, methanol and aldehyde volatiles. Distillers always discard the foreshots and never allow them to be part of the final product.

We keep ours separately to be used as hand sanitiser and cleaning spray for the distillery.

The next is the Heads

They can contain some undesirable, but not harmful, compounds and off-flavours

We add these to the Foreshots for hand sanitiser.

When we begin to get close to the hearts we use our nose and taste, knowing when to switch from heads to hearts is something that is learnt through practise and experience, although you can use temperature and abv as a yard stick.

When producing our dark rums we we start the heart run early collecting more of the heads into our finished product and go deeper into the tails to collect as much flavour as possible, with the white and gold rums we take later leaving a purer spirit.

Once hearts is complete we start moving into tails.

The tails are the final part of the distillation and contain some vegetal off-flavours. These are also typically discarded, however, thanks to those clever scientists and their discovery of rum oil we keep a section of the tails and add these back to the next spirit run, these rum oils are heavy in flavours and will leach into the heart run creating a more heavily flavoured rum.

Once our Hearts has been collected its time to proof down to barrel proof and age.


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