Spirits

Blackstrap Rum

Blackstrap rum is a near-black, heavy rum, generally 40% ABV and bitter-sweet with treacle, liquorice and burnt sugar. The name borrows from blackstrap molasses, which the Oxford Companion, a secondary source, describes as dark, rich, bitter and thick after several boilings, but Regulation (EC) 110/2008 gives the style no definition. Our Corn n’ Oil floats it over falernum, and our Jungle Bird stands it against Campari.

Quick Facts

ABV40% ABVOur recipes count it at 40%.

Legal categorySpirit

OriginCaribbean

Flavour Strengthstrong

Our keeping timeIndefinitely unopened. Once opened, years if kept sealed and upright out of the light, though the aroma fades slowly.

Storage

Sealed and upright out of direct light, like any spirit.

Allergens

None of the 14 listed allergens.

The ingredient

About Blackstrap Rum

Flavour Profile

Primary Flavours

MolassesLiquoriceCoffee

Tasting Notes

Black treacle, liquorice and burnt coffee over a dry, heavy rum, bitter-sweet rather than sweet.

The name comes from the third boiling

Sugar is made by boiling cane juice and crystallising the sugar out, and the syrup left over is molasses. Each boiling takes more sugar out. After several boilings, what remains is blackstrap molasses: dark, thick, mineral and much more bitter than the first or second grade.

Blackstrap rum borrows that name. There is no legal definition of it, and how much blackstrap molasses goes into a given bottle is up to the producer; what the word promises is a near-black, bitter-sweet rum that tastes of treacle rather than of caramel.

It floats, and the Corn n’ Oil depends on it

Our Corn n’ Oil puts 15ml of falernum on crushed ice and floats 60ml of blackstrap on top, poured gently off a bar spoon, then finishes with Angostura and a squeezed wedge of lime. It is served unstirred. The recipe also gives the Barbadian form, which is quite a different drink.

Two forms of the Corn n’ Oil in our recipe

Rum

Floated: 60ml blackstrap
Barbadian form: Aged Barbados rum

Falernum

Floated: 15ml, under the rum
Barbadian form: Stirred in

Method

Floated: Float, serve unstirred
Barbadian form: Stir together

First sip

Floated: Nearly neat rum
Barbadian form: The finished drink

	Floated	Barbadian form
Rum	60ml blackstrap	Aged Barbados rum
Falernum	15ml, under the rum	Stirred in
Method	Float, serve unstirred	Stir together
First sip	Nearly neat rum	The finished drink

Against Campari it holds its ground

Our Jungle Bird takes 45ml of blackstrap against 22.5ml of Campari, following the IBA. Lighter rums are overrun by the bitter aperitif; blackstrap answers it with a bitterness of its own, and the pineapple sits between the two.

It is a specialist, not a default

Poured in place of ordinary dark rum, blackstrap flattens the drink and turns it near-black. Keep it for the recipes that name it, and for a float when a drink wants a darker first sip.

Using it

Using Blackstrap Rum

Usage

60ml floated over 15ml of falernum in the Corn n’ Oil, and 45ml in the Jungle Bird, where it is the one rum heavy enough to meet 22.5ml of Campari. Use it where a recipe names it; as a general dark rum it takes over.

Pro Tip

For a Jungle Bird that reads too bitter, check the blackstrap before the Campari. Some bottles are much drier than others; a richer one, or 5ml less, brings the drink back.

Top Tips

Use it where a recipe names it, and in the measure given. As a default dark rum it flattens everything else.
Float it by pouring gently onto a bar spoon held against the glass. It sits on denser, sweeter liquids such as falernum.
If it floats, leave the drink unstirred. The first sips are meant to be nearly neat rum.
One bottle lasts a long time; in our experience it does not spoil once opened.

Possible Substitutions

Dark Rum: Sweeter, with less of the bitter edge
Gosling’s Black Seal Rum: A black rum; the drink comes out sweeter

Production Method

Made with heavy blackstrap molasses, the darkest and most mineral grade left after repeated sugar extraction, and typically darkened further in the blend. The result trades refinement for intensity on purpose.

Go further

More to explore

Common Questions

What is blackstrap rum?

A near-black, heavy rum, usually at about 40% ABV, with a bitter-sweet taste of treacle, liquorice and burnt sugar. The name comes from blackstrap molasses, the darkest syrup left after cane juice has been boiled three times. It is a style name; Regulation (EC) 110/2008 has no such category.

Is blackstrap rum the same as black rum?

Not quite. Black rum is a description of colour and body, and much of that colour can be added caramel. Blackstrap promises the bitter, treacle-heavy style. A black rum such as Gosling's Black Seal will make a Corn n’ Oil, but the drink comes out sweeter and less bitter.

What is blackstrap molasses?

The syrup left after cane juice has been boiled a third time and most of its sugar crystallised out. It is dark, thick and much more bitter than ordinary molasses. How much of it goes into a rum sold as blackstrap is the producer's choice; the word on the label promises a style, not a recipe.

Why does the Corn n’ Oil float the rum?

Spirit is lighter than a sweet syrup, so blackstrap poured slowly over falernum sits on top in a dark layer. The first sips are nearly neat rum, and the drink gets sweeter towards the bottom. Our version is left unstirred for that reason; on Barbados the drink is more often aged rum and falernum stirred together.

Can I use blackstrap rum in a Jungle Bird?

Our Jungle Bird uses it: 45ml of blackstrap, following the IBA, with 22.5ml of Campari, pineapple, lime and syrup. Its bitterness comes from burnt sugar and the Campari's from herbs, so neither covers the other. The recipe notes that a dark Jamaican rum was the earlier choice; it gives a fruitier drink.

What can I use instead of blackstrap rum?

A rich dark or black rum is the nearest, and the drink will be sweeter with less of the bitter edge. There is no exact swap. In the Corn n’ Oil, the island's own version stirs aged Barbados rum and falernum together instead.

Sources.

Checked between 16 October and 19 October 2026.

legislation.gov.uk, “Regulation (EC) No 110/2008, Annex II (as retained in UK law)”.
The Oxford Companion to Spirits and Cocktails (Frederick H. Smith), “molasses” (secondary source: blackstrap molasses, dark, rich, bitter and thick, after several boilings and low in sugar; blackstrap rum a light-bodied, column-distilled rum flavoured and coloured with molasses after distillation).

From the Guides

What blackstrap rum is made from How to Read a Rum Label

Make something

Made with Blackstrap Rum

Featured In These Cocktails

Jungle Bird Corn n’ Oil

Often Used With

Updated 19 October 2026

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