Getting started with distilling is very confusing, we understand!
Hobby distillers quickly discover that distilling is half-science lesson, half-engineering problem, and all experience. Experience is best gained when approached with knowledge in hand, and one of the first problems that distillers will face is the type of still that will suit their goals properly. This presents as a simple question:
“What is the difference between a pot still, and a reflux (or dual-purpose) still?”
A great question, as they are used for different purposes, and produce different results. This blog post will focus on explaining distillation differences between the two, let’s start with a pot still.
Pot Stills
Pot distilling is the traditional method of distillation that originated in the early 1800s, using a refined design of the earliest alembic stills, and is used for the production of flavorful spirits like whiskey, brandy, and rum. A pot still design is also excellent for maintaining the delicate aromatics of essential oil production.
A pot still is a simple design consisting of:
- Pot – The main bottom container where the wash is heated.
- Swan Neck – Where the vapors from the wash rise and reflux
- Lyne Arm – Transfers the vapor to the condenser
- Condenser – Cools the vapor to yield distillate
The diagram on the right shows our 26 Gallon 3″ Pot Still, with labels to show the different pieces!
These types of still design will simply collect/condense the alcohol vapor that boils off from the hot mash. This will result in an alcohol at about 40-60% purity, with a full, unique flavor profile.
If this distillate were put through the pot still again (and perhaps again!), it would increase in purity, and lose some of the flavor.
During distillation, the pot still is filled about two-thirds full of a fermented liquid (the wash) with an alcohol content of about 5–20%. This is also called “charging” the still. For whiskey distillation, the liquid used is a beer. For brandy production, it is a wine. The pot still is then heated so that the liquid is hot enough to boil off the ethanol.
During the distillation process, the vapor rises up the swan neck located on top of the pot still and then travels over the lyne arm. Next, it passes through the condenser, where it is cooled down, resulting in a distillate with a higher alcohol concentration than the original liquid. After one cycle of distillation, the resulting liquid is approximately 25-35% alcohol by volume, and can be increased with subsequent runs. This still is often used with multiple batches, and then the resulting distillations are combined into a large wash, and redistilled for even higher quality. Most Irish whiskeys are triple distilled using this method, while many Scottish whiskeys are only distilled twice.
Reflux Stills
Reflux distilling is a more advanced and efficient method commonly used for the production of high-proof neutral tasting spirits and industrial chemical separations.
A reflux still is a little more advanced than a pot still, and has some different components:
- Pot – The main bottom container where wash is heated.
- Column with Packing Material – Vapor chamber that allows for reflux action to occur
- Lyne Arm – transfers the vapor to the condenser
- Dephlegmator – An active condenser that is designed to condense and return some of the vaporized liquid back into the column of the still, allowing for better separation and purification, usually cooled by flowing water
- Condenser – Cools the vapor to yield distillate
You can see a labeled example of our 26 Gallon Reflux Still to the right.
The process is similar, the still is charged, and then is heated. While employing a reflux still, which consists of a column packed with a series of plates or packing material (such as our raschig rings, or copper mesh!) and a condenser, the liquid mixture is continuously circulated within the still, creating a reflux action. As the mixture is heated, vapors rise up the column and encounter cooler regions the higher they rise, where they condense. The dephlegmator is actively cooled by flowing water from an external source, and reflux can be controlled using a flow restriction on the water entering the dephlegmator.
The condensed vapors, known as reflux, flow back down the column, making contact with the rising vapors. This refluxing action allows for multiple distillation stages to occur within the column, resulting in improved separation and purification. The reflux still is designed to achieve higher levels of alcohol concentration and purity by separating out impurities and congeners more effectively. This also means that you do not have to double or triple your distillations to achieve a higher ABV content, as the action occurs directly in the column.
These stills are used to make clear, clean tasting spirits, such as vodka, gins, and fuel ethanol. Flavor profiles are easily added to the high proof, neutral spirit by way of infusion or barreling.
When starting out and deciding on where you would like to take your distillation journey, the amount of information and options available can be staggering. Choosing between a pot still and a reflux still depends on your preferences and the type of spirit you aim to create. Luckily, we also make it a little easier where we can, as all Moonshine Distiller reflux stills can be run in a pot still configuration. The best of both worlds!
Moonshine Distiller offers a wide range of both pot and reflux still options, perfectly suited for beginners looking to embark on their distillation journey!
Consider the distinctive features discussed here, and let your taste preferences and desired spirits guide you towards the right choice for your distilling adventure. Questions? Send us a message! Interested in other topics? Try our Youtube Channel!
Cheers!
