Four Pours and Several Beers Ago: Intro to Fermentation

Hello all, my name is Richard Drawdy, a husband and father of one son, an employee at Daktronics, and the part that leads me to this blog is a home brewer of about 27 months now. About a year ago I began talking to Matt about his homebrewing adventures which I originally discovered through this blog. Then a couple months ago I got the chance to brew with the AnderHoff duo. I noticed that they are in the beginning stages of the home brewers learning curve with myself being a little closer towards the apex. At that point I figured there may be a few things that I could lend in the way of advanced brewing tips that could be a helpful contribution to the blog. In my tenure I have made about 300 gallons of the home made libation we all love, totaling about 50 different recipes. It's not all about volume in this art its more about quality which leads me to my first topic I would like to present in my series of initial blog posts about improving your home brewed batches: quality fermentation.

There are many things that go into producing a malt sugar filled liquid which brewer's call wort, I will focus today on handling that wort once you get it into your fermenter. There are many variables that go into fermentation: wort composition, wort temperature, yeast variety, yeast cell count, yeast health, and fermenter size. All of this may seem like a lot to worry about and it is! But, to keep it simple you can follow these couple of steps in preparation for your brew day:
Review the specifications for your yeast. This will tell you important things like pitching rate requirements, temperature tolerance and alcohol tolerance. Effective fermentation is easily accomplished by shooting for the middle range on each of these requirements for your batch of home brew. Once you know the pitching rate requirements for your yeast you can use calculators available at yeastcalc.com or mrmalty.comin order to propagate or know how much to buy for your specific wort. Under pitching your yeast quantity can cause the wort to finish short of the targeted alcohol content as well as increase the amount of abrasive flavors produced by the yeast. Over pitching your yeast is less harmful but can cause the yeast to produce less flavors that you may want in the finished product.
Once you have the correct amount of yeast in your wort you then will want to focus on temperatures for the fermentation. Shooting for the lower end of your temperature range will restrain yeast flavor production, while the opposite will cause flavor production, some of which may be undesirable in the higher temperature ranges.
Now that we know the basics of fermentation lets walk through an example: Northern Brewer's Dead Ringer IPA Kit. When you buy the kit you also need to consider your schedule and whether you will have the time or equipment to make yeast starters, if not you will need to buy more than one liquid pack of yeast. This kit calls for a fermentation volume of 5 gallons of wort at an original gravity of 1.064. Yeastcalc.com says that this requires 222 billion cells of yeast or a pitching rate of 11.7 million cells per milliliter of wort. The Wyeast American Ale 1056 that comes with the kit contains 100 billion cells of yeast at the day it is produced. Based on the production date of the yeast pack you would need to buy 2 or 3 yeast packs. Or make a starter with 1 packet with a volume of 2-4 liters of starter wort again depending on the yeast packet age. I will assume that the yeast pack is 1 month old, meaning I will have 85 billion cells to start with. I will either need to buy 2 more yeast packs or make a 2.8 liter yeast starter to get to 222 billion cells needed for this healthy fermentation. Wyeast American Ale 1056 has a fermentation temp range of 60-72 F, 15-22 C. For this IPA I do not really want any yeast flavor contribution so I will shoot for 62 F on this fermentation. In order to achieve this temperature with some consistency but there are a variety of methods available. You could be sure that you brew during a time of the year that you have a room in your house will be the optimal temperature, or you could build yourself a fermentation control system with a fridge like I have done.