Glossary: D


Dephlegmators are a pre-condenser, typically at the top of the column, which sends distillate back towards the pot.

Acting as a cooler that distillers can control with precision, dephlegmators help increase the reflux in the column, and allows them to better control the rate at which the spirit can travel through to the condenser. This greatly aids the overall purity of the spirit, as well as being a useful tool to help increase the ABV of the spirit before collection, and therefore can also help increase yields when it comes to certain spirits such as Gin.

Some people refer to their reflux condensers (namely American distillers as they are more common there) as dephlegmators, but while similar, they are not quite the same. Dephlegmators use warmer/hot water (many hybrid stills use hot condenser water to feed their dephlegmators) rather than a separate cold-water feed. This is in contrast to a typical reflux condenser which does indeed control the reflux ratio but is not as finely tuned.


Just like with wine, Dry is the opposite of sweet.

As a flavour descriptor, Dry is the description given to a spirit when there is an absence of sweetness to taste, but it’s worth noting this is may not be due to a lack of sugars, it could just be the presence of some other taste that masks sweetness. For example, Angelica root is a botanical that can give the perception of dryness to the finish of a Gin, quinine and wormwood do the same in other drinks, irrespective of their being a touch of sugar in the recipe.

Denomination of Origin

Often abridged to three letters, 'protected denomination of origin' is a designation that protects geographical status and refers to products specific to a particular region or town, which convey a particular quality or characteristic of the designated area.

A DO status affords vital protection against fraud or tampering for spirits and ensures that the particularities of certain styles or the fact that they are made in certain regions are not just rules that are upheld locally, but internationally too. This helps to preserve the authenticity and quality of a spirit’s original production (such as Jamaican Rum).

Some obvious examples of this are Scotch, which can only be produced and bottled in Scotland, Tequila which is restricted to certain regions of Mexico, and Cognac where production is confined to certain region of France. Each spirit category has several DOP / DOM / DOC given to certain areas and / or styles with varying amount of rules to define what is and isn’t permissible.


Dunder is the liquid left in a boiler after distilling a batch of rum. Similar to backset in American Whisky (used for Sour Mashing), the stillage from a rum distillation is commonly poured back into a new wash to add flavour characteristics. 

Not just helpful in lowering the PH and helping to create optimal fermentation conditions, Dunder contains by-products that help in future fermentations in other ways, including dead yeast cells, which act as a yeast nutrient. While less common practice today, historically after a run the Dunder was sent to a "dunder pit” left to settle and develop bacteria that would aid in concentrating certain esters (like Butyric acid) – key to the flavour of some rum styles.

Typically, especially for the likes of Jamaican rum, around 20% of a new wash is dunder from one or more previous washes.


Representing around a quarter of the malt and un-malted cereals that are put into the fermentation process, draff is the spent grain left in the mash-tun after the wort has been drawn off. 

Many large-scale Scotch distilleries upcycle their draff as cattle food.


The term Dram comes from the old English apothecary system and are used to measure units of liquid volume. One dram is equal to 1/8 of an ounce. 

Today, it’s used for Whisky (particularly Scotch) and refers to a single serving of whisky. There isn’t an official measurement anymore and for most, a dram is considered to be the amount of whisky that you could reasonably swallow in one mouthful.

Diffuser (Difusor)

A Diffuser is an industrial sized tool, which looks like a giant conveyor belt and is used to extract the sugars from Agave. 

In a traditional Tequila making process, producers first cook the agave, and then extract the juice and its sugars, before fermenting and distilling it. Diffusers allow producers options in those early stages, and there are two ways in which they are commonly used. 

The first method uses the diffuser to extract the sugars once the agave has been cooked and shredded. In essence, the diffuser acts as a way of extracting the remaining sugars from fibres that would otherwise not be captured and help to increase the producer’s efficiency. 

The second use of a diffusor is a lot more controversial, as it is done without cooking the agave at all. In this instance, raw agave is loaded into the diffuser’s hopper. The agave pieces are then shredded and blasted with hot water almost simultaneously. While this results in extracting 99% of the starches of the agave (compare to a more typical 75%), running the shredding and cooking process in such a way has a big impact on flavour, which many connoisseurs deem as inferior.