Primary and Secondary Fermentation
21 Jan
Transferring beer from a primary to a secondary fermenter. Notice the trub sediment.
I was inspired by this thread on Brew Advice to compile my own findings on primary vs. secondary fermentation and when it’s necessary in the home brew process. Our list of equipment started off with a plastic carboy from Better Bottle and a bottling bucket sans lid. Recently, we discovered you can get airtight lids with a port for an airlock and so now we have the capability of fermenting in either container. In fact, a lot of home brewers go straight for the buckets, as they are often cheap, easy to move around, and block out light.
To tackle this issue, first we have to define what happens in primary and secondary fermentation. Primary fermentation is, in essence, when you start to make actual beer. After your wort has cooled and you add it to your fermenter, you pitch in your yeast and seal the container off. Within hours, the yeast start to eat the malt sugars and as a by-product they create alcohol and carbon dioxide. Now you have beer! Most recipes call for a fermentation of 7-14 days or until fermentation activity has slowed to almost nothing.