If you need to make a starter this is what you do:
- Put 200g of DME in a pot and add 2 liters of water (this will produce a 1040 starter)
- Bring this to the boil while stirring
- 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
- After 15 minutes*, cover the pot and place in cold water to bring the temperature of the wort down to 25c
- Put the cooled wort in a container (5 litre glass demi-john pictured above is perfect or you could use a erlinger flask)
- 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).
- 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
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......