In his book "Extreme Brewing," Sam Calagione, owner of Dogfish Head Craft Brewery states that secondary fermentation has little benefit to the home brewer and increases the chances of contamination.

In my own experience, it seems that very little actual fermentation takes place in the secondary. While a small amount of additional solids may settle out of the beer, is it worth doubling the risk of contamination?

Weigh in! Secondary or no secondary?

There are two reasons that I secondary my homebrew:

1. Clarity, especially in higher gravity beers.

2. Yeast. From what I understand, there are many dead yeast cells at the bottom of your fermenter. These dead yeast cells have the potential to give the beer off flavors.

Even if you use a single fermentor there are 2 stages, a primary and secondary stage, to the fermentation process.

I rack my beer from the primary fermentor to the secondary fermentor as soon as the active or primary stage is completed. The timing varies but is identifiable by a marked decrease in CO2 production (bubbling) and a noticeable decrease in flocculation (big clumps moving around in your beer).

I use 5.5 gallon glass carboys for both stages.

My primary fermentation usually lasts 2-4 days depending on OG and temperature.

In regards to the risk of contamination due to transferring you beer an additional time, if you follow a consistent practice of sanitation you should have no problems.

I secondary everything, never had a contam issue

I always use a secondary fermentation. It definitely helps clarify the beer. I keg all my beer, and without a secondary fermentation there would be a lot of yeast settling out that would cloud up several pints of beer. I have not had a contamination problem, but I sanitize everything that comes in contact with my beer.