Why Hot Cocktails On Draft Are A Bad Idea (And Even Dangerous)

A lot of people ask about doing hot cocktails on tap. This is a bad idea for a lot of reasons that aren’t immediately obvious. I thought I’d cover some here.

The first one is safety. Our drinks are often a veritable petri dish of nutrients that microorganisms love. With cold drinks this is often mitigated by acidity, but hot drinks usually have little to no acid. Cold drinks also may have higher amounts of alcohol (if the liquor is batched in).

Also, bacteria and yeast grow at different rates depending on temperature. This graph is a good illustration of what that looks like:



Hot drinks are perfectly safe when they’re above the temperature at which microorganisms become inactive or start dying. That’s why a pot of coffee can sit there for days and still be safe, if not very good tasting.

What you’ll notice from the curve is that microorganisms tend to grow faster and faster almost up to the point at which they stop. That means that even if your drink is safe at the higher temperature, when it starts to fall, it may have a long time at the top of the growth curve. Because of exponential growth, this means a drink can become dangerous before very long.

The second reason is that your beverage tubing and possibly other parts of the system are made from some form of plastic. Which specific plastic depends on which tubing or part, but generally they are ones chosen for cold applications. The materials used aren’t chosen at random; every part in the system is engineered for specific reasons (more on that in a second) and a system engineered for hot liquids would utilize different materials than one made for cold.

Plastics degrade with heat. If you’ve ever heard that you shouldn’t drink from a water bottle left in a hot car, this is why. You could be exposing your guests to carcinogens released as the plastic degrades from the heat and you would never know it.

The third reason is that it may damage your system. As I mentioned above, the parts of a draft system are all chosen for cold temperatures. There are a lot more parts involved than you might think. Your keg alone has 8 gaskets that are designed with a specific hardness. Gasket manufacturers use a scale called Shore durometer, and the gaskets chosen are the right hardness (usually around 70a) for the application. Too too soft and the gaskets might degrade prematurely and fail, too hard and they might not seal properly. A failed gasket in a keg system in use invariably means spewing your drink everywhere.

The keg you bought (unless you bought our silicone replacements) are likely using a rubber called Buna-N, a rubber that is particularly poor for high temperature applications. Your faucet will also have several gaskets in it, which are usually some combination of silicone and Buna-N, and none of which were designed for hot products.

And last but not least, it’s just a lot easier to serve out of a Cambro. A Cambro can keep a few gallons piping hot all day. No gas is required. Think about how you’re going to keep that keg hot all day. It’s pretty tough right? A Cambro needs no thought. You could even build a nice surround to hide the container (they’re not pretty by themselves) and make it look very much like a tap wall.

So as far as hot drinks on draft: yes, you can physically make it work, but you really shouldn't. You're putting the health of both your guests and your draft system at risk when you do.