Copper Stills vs Stainless Steel Stills

Still, derived from the word distillation, is an equipment used for distilling liquids. Distillation is the process through which components of a liquid are separated based on their boiling points for instance distilling alcohol to obtain whiskey. This process involves heating the mixture to boil selectively, then cooling it to allow vapor to condense. The liquid with the lower boiling point will evaporate first then after cooling and condensation becomes pure. 

Whether a seasoned distiller or a novice, the question of whether to use copper or stainless steel still is bound to come up at some point. This is critical as the element used has an impact on the taste and quality required as well as the investment required. For starters, stainless steel still is far cheaper than copper still and as such, would be the best option for beginners. On the other hand, copper stills are considered of higher quality as they give distillers more control over the process. Ultimately, the level of control determines the quality of the flavor of the final product. It would, therefore, be right to say here that if your aim is to get high-quality alcohol, copper stills will be your best bet. However, if cost is an issue for you, consider stainless steel stills.

It is important to note that, both stainless and copper stills have advantages and disadvantages and this is what we shall be looking at in detail in this article. 

1. Copper stills

Copper has been used over the years to construct traditional commercial stills. This is because copper, a great heat conductor, allows both natural reflux production and efficient condensation to occur within the still columns. In addition to being a great conductor, it also has the following advantages.

  • It is a good catalyst that breaks down sulfur and esters compounds that are produced in the process of fermentation. This results in high-quality distilled spirits. 
  • Copper elements in the metal prevent the production of ethyl carboxamide, a toxic substance that is produced from cyanides.
  • Copper gives you more control over the process such that the adjustments you make, for instance, increasing/decreasing heat power, reflect immediately on the still which greatly improves the flavor of the final distillate.  
  • Copper, as an element, is known scientifically to reduce bacterial contamination.

With these advantages, copper does not lack a few negatives. These are:

  • Copper tarnishes easily
  • It is difficult to clean

Clearly, the advantages of a copper still far outweigh its drawbacks.

2. Stainless steel stills

Stainless steel has many desirable qualities including:

  • It is resistant to tarnishing
  • It is a high-strength metal 
  • It is cheaper than copper 
  • It is relatively easy to clean

On the negative side, however:

  • Stainless steel is not as good a heat conductor as copper 
  • Stainless steel does not give you as much control over the distillation process as copper. Adjustments in heat power or cooling temperature take some time to reflect on the still.
  • Stainless steel will also not eliminate sulfur compounds produced during fermentation which affects the flavor of the final product. 

3. Stainless/copper hybrid stills

Because they draw from both the advantages of copper and stainless steel, hybrid stills are some of the best in function, cost, and durability. The best hybrid stills will be designed with a stainless steel boiler, copper column, and copper dome. This way, its cost will not be as high as that of copper still yet it will be well designed to conduct heat well and eliminate sulfur compounds. 

What to consider when choosing between a copper and stainless steel still?

Having considered the pros and cons of each material’s properties, this should guide you to making an informed decision of the still to go for. Both copper and stainless are best suited for certain tasks and/or situations and therefore, some factors you should consider when making a decision include: 

What do you want to distill? 

Is it water, essential oils, fuel alcohol, or spirits? While you can use both copper and stainless still to purify water and essential oils, this will not be the case with fuel alcohol which is better off distilled with stainless steel still. This is because fuel alcohol is a high-proof distillate. On the other hand, the best material for a spirit still is copper because of its ability to eliminate sulfur compounds in addition to great heat conduction property. 

What extra features are you looking for in a still? 

A basic still set-up includes a boiler, dome, column, and condenser. For better and more efficient functionality, however, some additions to the still will come in handy. You may opt for the following:

Temperature gauges

Some stills will come with built-in temp. gauges and these are good. For those that lack, it will be much easier working with a copper still to install the temperature gauge than stainless steel still which is a little tough and so requires welding tools. 

Electric heating elements

While you can install the electric heating elements for both the copper and stainless steel stills, it would be much easier installing one in a copper still than in a stainless steel still. Copper is generally an easy metal to work with. 

Bubble plates

The function of a bubble plate is to create more reflux in the column for additional distillation cycles. Bubble plates installation should be done on stainless steel still because it is tough thus it can withstand pressure. 

Copper mesh

A great addition to both types of stills if you want to achieve higher alcohol by volume (ABV) spirit. Copper eliminates sulfur compounds from your distillate. 

Sight glass

Apart from giving you a nice appearance, it will give you a view of what happens inside your boiler and you should be able, in a short time, to detect any issue in your process. However, because copper is not the best at withstanding pressure, a sight glass should be integrated on stainless steel still. 

Distiller’s parrot

Another great but optional addition to both stainless and copper stills. It is installed at the end of the condenser to help the distiller take a real-time reading of the alcohol percentage during the process of distilling

Should you build or buy a still?

Sometimes the material your still is made of can be determined by whether you have opted to buy or build one. Purchasing a ready-built still can be costly especially if you don’t have the lump sum. Building a copper still, on the other hand, could be appealing since copper is malleable and soft thus easy to work with. Unlike stainless steel, copper can be easily cut and soldered with little experience or expensive tools. Still, building a still requires some knowledge and sometimes skill. 

Conclusion

Given the different properties of copper and stainless steel materials, you need to know the type of process and expected product that you intend to have before making a decision. Another option is to combine the two materials in a way that reaps both durability, cost, and functionality benefits. A proven design involves using stainless steel to make strong and easy-to-clean pots along with copper to domes and columns for maximization of conductivity of steam vapors.