Another Brulosophy exBEERiment for you today. This is a question that comes up a lot at our home brew store. Do I have to do a secondary fermentation? There are a lot of practices in homebrewing that I believe stem from commercial beer brewing, and doing secondary fermentations is one of them.
The need for secondary fermentation arose because of yeast autolysis, or yeast death, and the off flavors that could be caused by it. Commercial brewers ferment in huge conical fermenters with thousands of gallons of beer in them and all of the yeast is settled in the cone of the fermenter. That puts a lot of pressure on the yeast causing autolysis. As homebrewers we obviously don't have anything like those conditions as we are fermenting in a 6.5 gallon bucket or carboy.
Are there reasons other than yeast autolysis that you would want to do a secondary fermentation? Absolutely, here are a few:
If you want to age a beer on fruit, or wood.
If you want to introduce another yeast like Brett or Lacto.
If it could be a long time before you can package it.
And the most important reason...to free up your fermenter so you can brew another beer!
Brulosophy's exBEERiment will definitely give you some insights on whether you should secondary or not. It's a great read! Cheers!
Pat Huffman, Brew and Grow Minnesota.