Ask Mr. Wizard

Can you step up yeast too much prior to pitching?


Vance J. Stringham Montague, Michigan asks,

I am brewing a batch of “honey brew” using 6 pounds of amber extract and 2 pounds of honey. I purchased Wyeast 1056 (American Ale yeast) in the 6-ounce size. The package said the yeast was “pitchable” but I stepped it up anyway. Actually, I stepped it up twice: first to about a pint (approximately 1.033 gravity) and two days later to a little less than two-thirds of a quart (1.050 gravity). I brewed everything, cooled it off, and pitched the yeast into my 6.5-gallon carboy.

This is the first time I have used a glass carboy, instead of a 7-gallon bucket. I still chose to use the airlock, never thinking the krauesen would fill the remaining 10 inches of headspace in the carboy. The next morning I got up and found the headspace filled to capacity with krauesen. It was also spewing out of the air lock! Can you step up yeast too much? What are my chances of contamination? I immediately sanitized some hose, a brass coupling and another stopper and set up a blow hose. Your insight would be graciously accepted.

Although you had a giant mess on your hands with your excited fermentation, you may have added a normal amount of yeast. In my experience, small yeast packets do not contain enough
Response by Ashton Lewis.