Archive for August, 2011

Harvesting and Freezing Yeast

Tuesday, August 23rd, 2011

One of the more spendy inputs in beer making is yeast. You can save money by purchasing dry yeast at around $2 a pack, which works very well and produces award-winning brews, but limits you to just a few strains. Liquid yeast runs anywhere from $7-$10 for enough yeast to pitch into a five gallon batch, while the rest of the inputs for a five gallon batch typically run about $20. So a full third of your cost resides in that yeast. But if you think about it, after fermentation you have yourself a bumper crop of pricy yeast cells just sitting there dormant at the bottom of your fermenter. If you’re a prolific brewer, you can immediately dump fresh wort onto that yeast cake and that works fine once, maybe twice, but you can get a lot more action than that off your investment for just a small amount of effort.

All you need to successfully harvest and freeze your yeast is a few readily available items and a ferocious passion for sanitization. For this small amount of effort, you can easily extend the life of one vial of yeast for 40 batches. Suddenly your $10 yeast purchase accounts for $0.25/batch. Here’s what you’ll need:

  • A 1qt. mason jar
  • 15ml test tubes w/caps
  • A small bottle of glycerine
  • A small foam cooler and a few ice packs

For this investment of under $30, you now have the power to extend your yeast’s work day.  This article on the Home Brewing Wiki painstakingly explains the steps for the harvest and freeze, so I won’t re-write that all here, but the basics are:

  • Sanitize the bejezus out of everything including your work space
  • Swirl the yeast back into suspension, dump into the mason jar and cap it
  • Let the heavy trub settle out for 20 minutes in the fridge
  • Carfully fill 3 tubes to the top and cap
  • Place the tubes in the fridge (upright) and let the yest settle.
  • Swirl up the yeast in the mason jar, cap it and let it settle again in the fridge for 20 minutes
  • decant the liquid off the settled yeast in the tubes and fill again from the mason jar

Repeat those steps 3x and you’ll easily have three vials about half full of lovely yeast.  Add some water/glycerine mix to each vile (to keep the cells from bursting), cap it and shake it up and you now have freezable yeast cells. Stick them in the foam cooler with the ice packs to prevent any premature thawing in the freezer. Pop out a vile a week or so before you need it and put it in the fridge for four or five days to thaw.  Let it come to room temp while you’re making a starter (yes you must make a starter for this to work well), let the starter go for a few days to build a viable colony and pitch!

You can then harvest and freeze three vials off of that batch! You can repeat this safely two more times this extending the original vial out four full generations.  Beyond that the risk of mutation becomes too high and you’ll want to start over with a fresh vial of yeast. I guess if you keep going you end up with zombie beer or something.  Nobody wants zombie beer.

Handy Chart for tracking yeast evolution (click for larger image)

A Great Time to be Alive as a Beer Lover!

Tuesday, August 9th, 2011

Click if you like saying, "WTF?!" when looking a a graph.

In the years before Prohibition, there were just under 1,600 breweries in operation in the US. As of last year, it would appear we have surpassed that level of with 1,740 breweries in operation today, according to the Brewer’s Association. However, when you look and the production output of those breweries, you’ll notice that we are at nearly 4x the highest level ever produced. Now if that isn’t enough reason to rejoice, the brewer’s association also reports that there are an additional 725 breweries in the planing stage for this year!


There was a time when the US boasted over 4000 breweries in 1873, but their actual output was nothing compared to what is produced today. Now to be fair, that many breweries is probably what led the whole “Temperance Movement” to gain the traction it did, so perhaps there is a cautionary tale in here somewhere. But still, 725 new breweries! If this keeps up the Brewer’s association is going to have to move the Great American Beer Festival to some place with more than just a measly 2.2 million square feet of exhibit space! Is this a “beer bubble”? Yeah, maybe, but it could also signal a switch to the local brew pub ruling the scene with new beer styles and more room to experiment. At a minimum it’s going to be an awesome ride for as long as it lasts!