Harvesting Yeast in Dry-Hopped Beers

Whether you’re starting from a dry or liquid yeast culture, both can give you the opportunity to harvest and repitch. Some of the benefits of reusing yeast include cost savings and better and more reliable yeast performance. However, a warning: any issue in the initial batch of yeast will carry over into subsequent generations, so if the yeast isn’t in good shape, the next generation may suffer as well. 

Dry hopping can be a major stressor for yeast, and pitching yeast from beers that have been dry hopped is a no-go. That doesn’t mean there aren’t ways around it! Here are a few tips to get you started.

While this is not necessarily what we recommend — it’s very difficult to do early dry hopping if you’re planning to repitch yeast. If you intend to reuse yeast from your early dry-hopped beer, you’ve got to harvest the yeast during krausen. Jessica Young (formerly of Bearded Iris in Nashville, TN) developed the serial repitching method. 

Effectively, you’re harvesting two days after you brew, so you’ll need to be brewing very regularly to make it work when early dry hopping.

This is the most effective time for harvesting, and definitely what we recommend: wait until you get a good harvest on the tank and then dry hop so you can reuse that yeast. When you’re already investing a lot in the hops, repitching your yeast is a good way to make those investments work for you and keep costs down.

Generally you’ll want to time your harvest when viability is still high, and enough yeast has collected at the bottom of the cone. Close to terminal gravity is a great time to harvest from the cone. There is a sweet spot right as the fermentation is approaching terminal when you can harvest yeast and still dry hop when the yeast is active. This can help encourage hop creep to occur faster. Keep in mind that the initial burst of from the cone is trub and potentially a small amount of dead yeast cells — keep a close eye on the color and consistency of what’s coming down the line to make sure you grab the healthy yeast slurry, and be sure not to draw the slurry too quickly or you will punch through straight to beer.

Keep track of your fermentation data and strive for consistency. It might take adjusting your repitching schedule to new yeast or a new dry hopping approach, but these tips should definitely help you get started with harvesting liquid yeast. The overall goal is to have the healthy and predictable fermentations and save some money while you are at it.