Can you use a keg as a fermenter?

Answered by Brandon Riddell

Can you use a keg as a fermenter? Using a keg as a fermenter has become increasingly popular among homebrewers and even some commercial brewers. It offers several advantages over traditional fermentation vessels, such as carboys or plastic buckets.

One of the main benefits of using a keg as a fermenter is the ability to use CO2 to transfer the from primary to secondary. This process is commonly known as closed transfer and eliminates the need for siphoning or relying on gravity. It is a much more sanitary and efficient method, as it minimizes the risk of introducing oxygen or contaminants to the beer during transfer.

To use a keg as a fermenter, you will need a few additional pieces of equipment. Firstly, you will need a keg with a removable lid or a dedicated fermenting keg with a wide-mouth opening. These types of kegs are specifically designed for fermentation and often come with a built-in airlock or a bung for attaching an airlock.

Next, you will need a way to seal the keg and create an airtight fermentation environment. This can be achieved by using a pressure relief valve or a spunding valve, which allows excess pressure to escape while maintaining a closed system. It is important to note that during active fermentation, CO2 production will create pressure inside the keg, so it's crucial to have a way to release that pressure safely.

Once you have your keg and the necessary equipment, the fermentation process is relatively straightforward. You can transfer your cooled wort directly into the keg, leaving some headspace for the krausen to form. Attach the lid with the airlock or bung, making sure it is securely sealed. If using a pressure relief valve or spunding valve, set it to the desired pressure to allow for controlled release of excess CO2.

During fermentation, the CO2 produced will collect in the headspace of the keg, creating a protective blanket over the beer. This helps to prevent oxidation and minimizes the risk of contamination. You can monitor the progress of fermentation by observing the airlock activity or checking the pressure gauge on the relief valve.

Once fermentation is complete, you can use CO2 to transfer the beer to a secondary keg or directly to serving kegs. This closed transfer method ensures minimal exposure to oxygen and reduces the chances of picking up any off-flavors or contaminants. It also allows for clearer beer, as any sediment or trub from primary fermentation can be left behind.

Using a keg as a fermenter has several advantages beyond closed transfer. Kegs are durable and easy to clean, making them a hygienic option for fermentation. They are also stackable, which can be beneficial for those with limited storage space. Additionally, kegs are often used for serving beer, so you can eliminate the need for additional vessels during the process.

Using a keg as a fermenter is a convenient and effective method for homebrewers and commercial brewers alike. It allows for closed transfer using CO2, which reduces the risk of oxidation and contamination. With the right equipment, you can easily ferment your beer in a keg and enjoy the benefits of this versatile vessel. Cheers!