Friday, September 7, 2012

AG #16 - Yeast Starter

When I last posted I expected to be brewing the third version of my house stout the following week, however that was over a month ago and still no brew! August turned into a hectic month and so brewing got put on the back burner (excuse the pun). However with our recent spell of good weather I am hoping to get to brew this beer on Sunday. However the one problem is that my liquid yeast (Wyeast 1084 Irish Ale) has been sitting in my beer fridge now for nearly two months and I am not absolutely sure that this yeast is still viable. Due to the fact that I have no back up yeast available I decided to do a yeast starter today (pictured), by Sunday I should know if the yeast is fit for purpose.

If you need to make a starter this is what you do:
  1. Put 200g of DME in a pot and add 2 liters of water (this will produce a 1040 starter)
  2. Bring this to the boil while stirring
  3. Boil for 15 minutes, it is also a good idea to add a few leafs/pellets of the hops you will be using for the main brew
  4. After 15 minutes*, cover the pot and place in cold water to bring the temperature of the wort down to 25c
  5. Put the cooled wort in a container (5 litre glass demi-john pictured above is perfect or you could use a erlinger flask)
  6. Add your yeast and give it a good shake (you can also shake periodically over the next day or so to get some oxygen into the solution).
  7. When it comes to brew day you can either dump the whole mixture into your fermenter or alternatively you can decant off the liquid and add only the yeast slurry to your fermenter
* always remember that this is essentially a mini brew and so sanitise as you would on a regular brew day.

The benefits of a yeast starter are that it can make sure that the yeast you have is viable (if your starter doesn't ferment, the yeast is probably dead) and secondly it increases the cell count of the yeast thus ensuring a healthy fermentation for your main batch.

Barring any last minute delays I should have a nice stout lined up for October, now to start thinking about what I want to drink this Christmas......


Shane Glover said...

Hey, I've been thinking so starting a homebrew, would you say it's a hard thing to get started?

Mark (Halite) said...

Its not difficult to get started and there are some great articles on that will help you along the way, happy brewing.