Can you use metal lids for fermentation?

Answered by Willie Powers

It is absolutely possible to use metal lids for fermentation. In fact, metal lids were commonly used for fermentation before plastic lids became popular. However, there are a few things to keep in mind when using metal lids for fermentation.

Firstly, it is important to ensure that your metal lids are rust-free and in good condition. Rust can contaminate your fermentation and lead to off flavors or even spoilage. So, before using metal lids, give them a thorough inspection and make sure they are clean and free of any rust or corrosion.

Secondly, when using metal lids for fermentation, it is recommended to screw them on loosely to allow gases to escape. Fermentation produces carbon dioxide and other gases, and if the lid is tightly sealed, these gases can build up pressure inside the jar, potentially causing it to burst or leading to a messy overflow. By leaving the metal lids slightly loose, you provide an avenue for the gases to escape and prevent any accidents.

One advantage of using metal lids is that they are generally more airtight than plastic lids. This can be beneficial if you are fermenting foods that require an anaerobic environment, such as sauerkraut or kimchi. An airtight seal helps to create the ideal conditions for fermentation, allowing beneficial bacteria to thrive and preventing the growth of harmful microorganisms.

On the other hand, one downside of metal lids is that they are not as easily burped or opened as plastic lids. “Burping” refers to the process of releasing built-up gases during fermentation. This is done by slightly loosening the lid to allow the gases to escape and then tightening it back up. With metal lids, it may be a bit more challenging to burp the jars, but it is still possible. You can simply unscrew the lid slightly and then retighten it after the gases have been released.

Using metal lids for fermentation is perfectly fine as long as they are rust-free and in good condition. Just remember to screw them on loosely to allow gases to escape and be mindful of burping the jars if necessary. Ultimately, the choice between metal and plastic lids comes down to personal preference and the specific requirements of your fermentation.